Today in Astronomy

January 18: Arthur Scott King

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Arthur Scott King

January 18, 1876 – April 17, 1957

Arthur Scott King was an American physicist and astrophysicist.

In 1895 Arthur graduated from Fresno High School, then attended the University of California, Berkeley. He developed an interest in physics, and in 1899 he was admitted into their graduate school. He was awarded a Ph.D. in 1903, the first ever Ph.D. in physics awarded by that university.

After winning a Whiting Fellowship, he spent two years in Germany, studying at Bonn and Berlin and travelling in Europe. His academic interests were focused on spectroscopy, and at the time these institutions were leaders in the field.

In 1905 he returned to Berkeley and became an instructor. The following year published a paper describing the use of an electric furnace for use in spectroscopy.

He was offered a position at Mt. Wilson Observatory in 1907, and took his leave from Berkeley. He spent much of the remainder of his career studying the spectra of elements and molecules, with particular focus on rare earth elements. He also performed studies of meteors, including their spectra and directional paths. In 1929, he collaborated with Dr. Raymond T. Birge to discover the isotope Carbon-13, based on differences in the spectrum.

Between 1901 and his retirement he published well over 200 papers in scientific journals. He served as president of the American Meteorical Society for a period, and also as president of the Astronomical Society of the Pacific in 1941. In 1943 he retired, but he became involved in war research at CalTech. There he studied the ballistics of torpedoes launched from aircraft.

The crater King on the far side of the Moon was co-named for him and Edward S. King.

Today in Astronomy: January 18: Warren De la Rue

The Astronomy Compendium: January 18

January 16: Johannes Schöner

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Johannes Schöner

January 16, 1477 – January 16, 1547

Johannes Schöner was a renowned and respected German polymath. It is best to refer to him using the usual 16th century Latin term "mathematicus", as the areas of study to which he devoted his life were very different from those now considered to be the domain of the mathematician. He was a priest, astronomer, astrologer, geographer, cosmographer, cartographer, mathematician, globe and scientific instrument maker and editor and publisher of scientific tests.

In his own time he enjoyed a European-wide reputation as an innovative and influential globe maker and cosmographer and as one of the continents leading and most authoritative astrologers. Today he is remembered as an influential pioneer in the history of globe making and as a man who played a significant role in the events that led up to the publishing of Copernicus' "De revolutionibus" in Nürnberg in 1543.

Schöner had made still unpublished data of Mercury observations from Walther available to Copernicus, 45 observations in total, 14 of them with longitude and latitude. Copernicus used three of them in "De revolutionibus", giving only longitudes, and falsely attributing them to Schöner. The values differed slightly from the ones published by Schöner in 1544.

In 1538, Georg Joachim Rheticus, a young professor of mathematics at Wittenberg, stayed for some time with Schöner who convinced him to visit Nicolaus Copernicus in Frauenburg. In 1540, Rheticus dedicated the first published report of Copernicus work, the Narratio prima, to Schöner. As this was well received, Copernicus finally agreed to publish his main work, and Rheticus prepared Copernicus' manuscript for printing.

A crater on Mars is named in his honor.

January 12: Royal Aeronautical Society

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The Royal Aeronautical Society

Founded in 1866 the Royal Aeronautical Society, also known as the RAeS, is a multidisciplinary professional institution dedicated to the global aerospace community.

The objectives of The Royal Aeronautical Society include; to support and maintain the highest professional standards in all aerospace disciplines; to provide a unique source of specialist information and a local forum for the exchange of ideas; and to exert influence in the interests of aerospace in both the public and industrial arenas.

Throughout the world's aerospace community the name of The Royal Aeronautical Society is widely known and respected. Many practitioners from all disciplines within the aerospace industry use the Society's designatory post-nominals such as FRAeS, CRAeS, MRAeS, AMRAeS, and ARAeS (incorporating the former graduate grade, GradRAeS).

The Staff of the Royal Aeronautical Society are based at the Society's headquarters at No.4 Hamilton Place, London. Although centred in the United Kingdom, the Royal Aeronautical Society is a worldwide society with an international network of 63 branches.

January 12: Sergey Pavlovich Korolyov

The Astronomy Compendium: January 12

January 11: Lunar Prospector

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Lunar Prospector entered lunar orbit on January 11, 1998.

The Lunar Prospector mission was the third selected by NASA for full development and construction as part of the Discovery Program. At a cost of $62.8 million, the 19-month mission was designed for a low polar orbit investigation of the Moon, including mapping of surface composition and possible polar ice deposits, measurements of magnetic and gravity fields, and study of lunar outgassing events. The mission ended July 31, 1999, when the orbiter was deliberately crashed into a permanently shadowed area of the Shoemaker crater near the lunar south pole in an unsuccessful attempt to detect the presence of water.

Data from the mission allowed the construction of a detailed map of the surface composition of the Moon, and helped to improve understanding of the origin, evolution, current state, and resources of the Moon. Several articles on the scientific results were published in the journal Science.

Lunar Prospector was managed out of NASA Ames Research Center with the prime contractor Lockheed Martin. The Principal Investigator for the mission was Dr. Alan Binder.

The probe also carried a small amount of the remains of Dr. Eugene Shoemaker (April 28, 1928 – July 18, 1997), astronomer and co-discoverer of Comet Shoemaker-Levy 9, to the moon for a space burial.

January 11: William Tyler Olcott

The Astronomy Compendium: January 11

January 10: Eugène Joseph Delporte

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The Amor group of asteroids.

Eugène Joseph Delporte

January 10, 1872 – October 19, 1955

Eugène Joseph Delporte was a Belgian astronomer.

He discovered a total of sixty-six asteroids. Notable discoveries include 1221 Amor (which lent its name to the Amor asteroids) and the Apollo asteroid 2101 Adonis. He discovered or co-discovered some comets as well, including periodic comet 57P/du Toit-Neujmin-Delporte.

He worked in the Observatoire Royal de Belgique (Belgian Royal Observatory), situated in the town of Uccle (after which the asteroid 1276 Ucclia is named).

In 1930 he fixed the modern boundaries between all of the constellations in the sky, along lines of right ascension and declination for the epoch B1875.0.

The Lunar crater Delporte is named in his honor.

January 10: Simon Marius

The Astronomy Compendium: January 10

January 8: Johannes Fabricius

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Johannes Fabricius

January 8, 1587 – March 19, 1616

Johannes Fabricius, eldest son of David Fabricius (1564-1617), was a German astronomer and a discoverer of sunspots, independently of Galileo Galilei.

Johannes was born in Resterhafe (Friesland). He returned from university in the Netherlands with telescopes that he and his father turned on the Sun. Despite the difficulties of observing the sun directly, they noted the existence of sunspots, the first confirmed instance of their observation (though unclear statements in East Asian annals suggest that Chinese astronomers may have discovered them with the naked eye previously, and Fabricius may have noticed them himself without a telescope a few years before). The pair soon invented camera obscura telescopy so as to save their eyes and get a better view of the solar disk, and observed that the spots moved. They would appear on the eastern edge of the disk, steadily move to the western edge, disappear, then reappear at the east again after the passage of the same amount of time that it had taken for it to cross the disk in the first place.

Copies of a map he made of Frisia in 1589 are also still extant. He is also named in Jules Verne's From the Earth to the Moon as someone who claimed to have seen lunar inhabitants through his telescope, though that particular fact is merely part of Verne's fiction.

The Lunar crater Fabricius is named after his father, David Fabricius.

January 8: Galileo Galilei

January 8: Stephen Hawking

The Astronomy Compendium: January 8

January 7: Francesco Carlini

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Carlini crater on the Moon

Francesco Carlini

January 7, 1783 – August 29, 1862

Francesco Carlini was an Italian astronomer.

Born in Milan, he became director of the observatory there in 1832. He published Nuove tavole de moti apparenti del sole in 1832. In 1810, he had already published Esposizione di un nuovo metodo di construire le taole astronomiche applicato alle tavole del sole. Together with Giovanni Antonio Amedeo Plana, he participated in a geodetic project in Austria and Italy. During this trip in 1821 he took pendulum measurements on top of Mount Cenis, Italy, from which he calculated one of the first estimates of the density and mass of the Earth.

The Lunar crater Carlini is named in his honor.

January 7: Jovian Moons

The Astronomy Compendium: January 7

December 20: Walter Sydney Adams

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Walter Sydney Adams

December 20, 1876 – May 11, 1956

Walter Sydney Adams was an American astronomer.

He was born in Antioch, Syria to missionary parents, and was brought to the U.S. in 1885. He graduated from Dartmouth College in 1898, then continued his education in Germany. After returning to the U.S., he began a career in Astronomy that culminated when he became director of the Mount Wilson Observatory.

His primary interest was the study of stellar spectra. He worked on solar spectroscopy and co-discovered a relationship between the relative intensities of certain spectral lines and the absolute magnitude of a star. He was able to demonstrate that spectra could be used to determine whether a star was a giant or a dwarf.

In 1915 he began a study of the companion of Sirius and found that despite a size only slightly larger than the Earth, the surface of the star was brighter per unit area than the Sun and it was about as massive. Such a star later came to be known as a white dwarf.

Along with Theodore Dunham, he discovered the strong presence of carbon dioxide in the infrared spectrum of Venus.

Adams received the Gold Medal of the Royal Astronomical Society (1917), the Henry Draper Medal (1918), the Bruce Medal (1928) and the Henry Norris Russell Lectureship (1947).

The asteroid 3145 Walter Adams and a crater on Mars are named in his honor. The crater Adams on the Moon is jointly named after him, John Couch Adams and Charles Hitchcock Adams.

December 19: Albert Michelson

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Albert Michelson

December 19, 1852 – May 9, 1931

Albert Abraham Michelson was an American physicist known for his work on the measurement of the speed of light and especially for the Michelson-Morley experiment. In 1907 he received the Nobel Prize in Physics. He became the first American to receive the Nobel Prize in sciences.

Michelson was born in Strzelno, Provinz Posen in the Kingdom of Prussia (now Poland). He moved to the United States with his parents in 1855, when he was two years old.

President Ulysses S. Grant awarded Michelson a special appointment to the U.S. Naval Academy in 1869. During his four years as a midshipman at the Academy, Michelson excelled in optics, heat and climatology as well as drawing. After his graduation in 1873 and two years at sea, he returned to the Academy in 1875 to become an instructor in physics and chemistry until 1879. In 1879, he was posted to the Nautical Almanac Office, Washington, to work with Simon Newcomb, but in the following year, he obtained leave of absence to continue his studies in Europe. He visited the Universities of Berlin and Heidelberg, and the Collège de France and École Polytechnique in Paris.

Michelson was fascinated with the sciences and the problem of measuring the speed of light in particular. While at Annapolis, he conducted his first experiments of the speed of light, as part of a class demonstration in 1877. After two years of studies in Europe, he resigned from the Navy in 1881. In 1883 he accepted a position as professor of physics at the Case School of Applied Science in Cleveland, Ohio and concentrated on developing an improved interferometer. In 1887 he and Edward Morley carried out the famous Michelson-Morley experiment which seemed to rule out the existence of the aether. He later moved on to use astronomical interferometers in the measurement of stellar diameters and in measuring the separations of binary stars.

In 1907, Michelson had the honor of being the first American to receive a Nobel Prize in Physics "for his optical precision instruments and the spectroscopic and meteorological investigations carried out with their aid". He also won the Copley Medal in 1907, the Henry Draper Medal in 1916 and the Gold Medal of the Royal Astronomical Society in 1923.

The Lunar crater Michelson is named in his honor.

December 18: Gottfried Kirch

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Gottfried Kirch

December 18, 1639 — July 25, 1710

Gottfried Kirch was a German astronomer. He first worked as a calendar-maker in Saxonia and Franconia. He began to learn astronomy in Jena, and studied under Hevelius in Danzig. In Danzig in 1667, Kirch published calendars and built several telescopes and instruments.

In 1686, Kirch went to Leipzig. There, he observed the great comet of 1686, together with Christoph Arnold. At Leipzig, Kirch also met his second wife, Maria Winckelmann (1670-1720), who had learned astronomy from Arnold. In 1688, he invented and charted the now obsolete constellation Sceptrum Brandenburgicum, the Brandenburg Scepter. Later, in 1699, he observed comet 55P/Tempel-Tuttle but this observation was not recognized until later analysis by Joachim Schubart.

In 1700, Kirch was appointed by Frederick I of Prussia as the first astronomer of the Prussian Royal Society of Sciences.

Kirch studied the double star Mizar, and discovered both the Wild Duck Cluster (Messier 11) (1681) and Globular Cluster M5 (May 5, 1702). He also discovered the variability of the Mira variable Chi Cygni in 1686.

The Lunar crater Kirch and the asteroid 6841 Gottfriedkirch are named in his honor.

December 6: Yoshio Nishina

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Yoshio Nishina

December 6, 1890 – January 10, 1951

Yoshio Nishina was the founding father of modern physics research in Japan. He co-authored the well-known Klein-Nishina Formula. He was a principal investigator of RIKEN and mentored generations of physicists, including two Novel Laureates: Hideki Yukawa and Sin-Itiro Tomonaga. During World War II he was the head of the Japanese atomic program.

Nishina was born in Satosho, Okayama and graduated from Tokyo Imperial University in 1918. After graduation, he became a staff member at RIKEN. In 1921 he was sent to Europe for research. He visited some European universities and institutions, including Cavendish Laboratory, Georg August University of Göttingen, and University of Copenhagen. In Copenhagen he did research with Niels Bohr and they became good friends. In 1928 he wrote a paper on incoherent or Compton scattering with Oskar Klein in Copenhagen, from which the Klein-Nishina formula derives.

In the same year he returned to Japan, where he endeavored to foster an environment for the study of quantum mechanics. He invited some Western scholars to Japan including Heisenberg, Dirac and Bohr to stimulate Japanese physicists. He detected what turned out to be the muon in cosmic rays, independently of Anderson et al.

His research was concerned with cosmic rays and particle accelerator development.

In 1946 he was awarded the Order of Culture by the Emperor of Japan.

The Lunar crater Nishina is named in his honor.

December 5: Werner Heisenberg

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Werner Heisenberg

December 5, 1901 – February 1, 1976

Werner Heisenberg was a German theoretical physicist who made foundational contributions to quantum mechanics and is best known for asserting the uncertainty principle of quantum theory. In addition, he also made important contributions to nuclear physics, quantum field theory, and particle physics.

Heisenberg, along with Max Born and Pascual Jordan, set forth the matrix formulation of quantum mechanics in 1925. Heisenberg was awarded the 1932 Nobel Prize in Physics.

Following the war, he was appointed director of the Kaiser Wilhelm Institute for Physics, which was soon thereafter renamed the Max Planck Institute for Physics. He was director of the institute until it was moved to Munich in 1958, when it was expanded and renamed the Max Planck Institute for Physics and Astrophysics.

Heisenberg was also president of the German Research Council, chairman of the Commission for Atomic Physics, chairman of the Nuclear Physics Working Group, and president of the Alexander von Humboldt Foundation.

Heisenberg studied under Arnold Sommerfeld, who was born on this date in 1868. Sommerfeld was a German theoretical physicist who pioneered developments in atomic and quantum physics, and also educated and groomed a large number of students for the new era of theoretical physics. He introduced the fine-structure constant into quantum mechanics.

December 4: Wilhelm Tempel

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Ernst Wilhelm Leberecht Tempel

December 4, 1821 – March 16, 1889

Wilhelm Tempel, was a German astronomer who worked in Marseille until the outbreak of the Franco-Prussian War in 1870, then later moved to Italy.

He was a prolific discoverer of comets, discovering or co-discovering 21 in all, including Comet 55P/Tempel-Tuttle, now known to be the parent body of the Leonid meteor shower, and 9P/Tempel, the target of the NASA probe Deep Impact in 2005.

Other periodic comets that bear his name include 10P/Tempel and 11P/Tempel-Swift-LINEAR.

The asteroid 3808 Tempel and the Lunar crater Tempel are named in his honor.

November 20: Edwin Powell Hubble

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Edwin Powell Hubble

November 20, 1889 – September 28, 1953

Edwin Hubble was an American astronomer. He profoundly changed our understanding of the universe by demonstrating the existence of other galaxies besides the Milky Way. He also discovered that the degree of redshift observed in light coming from a galaxy increased in proportion to the distance of that galaxy from the Milky Way. This became known as Hubble's law, and would help establish that the known universe is expanding.

In 1919, Hubble was offered a staff position in California by George Ellery Hale, the founder and director of the Carnegie Institution's Mount Wilson Observatory, near Pasadena, California, where he remained on the staff until his death. Shortly before his death, Mount Palomar's giant 200-inch (5.1 m) reflector Hale Telescope was completed, and Hubble was the first astronomer to use it. Hubble continued his research at the Mount Wilson and Mount Palomar Observatories, where he remained active until his death.

Edwin Hubble's arrival at Mount Wilson, California, in 1919 coincided roughly with the completion of the 100-inch (2.5 m) Hooker Telescope, then the world's largest telescope. At that time, the prevailing view of the cosmos was that the universe consisted entirely of the Milky Way Galaxy. Using the Hooker Telescope at Mt. Wilson, Hubble identified Cepheid variables (a kind of star; see also standard candle) in several spiral nebulae, including the Andromeda Nebula. His observations, made in 1922–1923, proved conclusively that these nebulae were much too distant to be part of the Milky Way and were, in fact, entire galaxies outside our own. This idea had been opposed by many in the astronomy establishment of the time, in particular by the Harvard University-based Harlow Shapley. Hubble's discovery, announced on January 1, 1925, fundamentally changed the view of the universe.

Hubble also devised the most commonly used system for classifying galaxies, grouping them according to their appearance in photographic images. He arranged the different groups of galaxies in what became known as the Hubble sequence.

Hubble was awarder the Bruce Medal (1938) and the Gold Medal of the Royal Astronomical Society (1940).

The Lunar crater Hubble, asteroid 2069 Hubble and the orbiting Hubble Space Telescope are named in his honor.

October 30: Marcin Poczobutt

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Marcin Odlanicki Poczobutt

October 30, 1728 – February 7, 1810

Marcin Poczobutt was a Polish-Lithuanian astronomer, jesuit and mathematician.

He became mathematics professor and rector of the Vilnius University where he organized the construction of the university's observatory and the purchase of the equipment. He also made observations of solar and lunar eclipses, comets and asteroids. In addition, he made measurements of Mercury to compute an orbit, and also determined the geographic coordinates of locations in Lithuania, including Vilnius.

He was granted the title of the King's Astronomer and became a member of the British Royal Academy of Science.

The Lunar crater Poczobutt is named in his honor.

October 29: Richard Hawley Tucker

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Richard Hawley Tucker

October 29, 1859 – March 31, 1952

Richard Tucker was an American astronomer.

He was born in Wiscasset, Maine to a ship-owning and sea-faring family. After a brief stint at sea starting at age 14, he attended Lehigh University where he studied civil engineering but became interested in the study of astronomy. He graduated in 1879 and became an assistant at Dudley Observatory. He remained there for four years, and briefly worked with the United States Coast and Geodetic Survey.

In 1883 he joined Lehigh as an instructor of mathematics and astronomy. A year later he was offered a position with the Argentine National Observatory, where he would assist in a survey of the southern night sky. He remained there for nine years, then joined the staff of Lick Observatory in 1893. He remained at Lick until 1908, operating the Meridian Circle program to make precise measurements of star positions.

In 1908 he would travel to San Louis, Argentina as part of an expedition to measure the positions of stars in the southern part of the sky. These measurements were to be incorporated into a catalog for Dudley Observatory. During his time there he made 20,800 observations of stars.

After his work in Argentina, he returned to Lick Observatory. In 1914 he married Ruth Standen, a secretary at Lick. He remained at the observatory until he retired in 1926, when he became Astronomer Emeritus. He spent his retirement years in Palo Alto, California.

During his career he published fifty three scientific articles.

The Lunar crater Tucker is named in his honor.

October 27: Thomas Gwyn Elger

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Image Credit: C.A. Wood Collection

Thomas Gwyn Empy Elger

October 27, 1836 – January 9, 1897

Thomas Elger was an English lunar mapper and the first director of the Lunar Section of the British Astronomical Association (BAA).

He was born in Bedford, where the family had been established for several generations. His father Thomas Gwyn Elger (1794–April 4, 1841) was an architect and builder. Grandfather, father and son engaged in the town politics, and all held the post of mayor.

He studied at University College London and adopted the profession of a civil engineer. He was engaged in several important works, including the Metropolitan Railway and the Severn Valley Railway. His surveys for railway construction in Holstein were put to a stop by the war with Prussia and Austria in 1864.

Soon afterwards he relinquished the active pursuit of his profession and devoted himself to scientific studies. He had developed a strong taste for astronomy already at an early age and erected his first observatory in Bedford. Elger observed with an 8.5 inch reflector. His sketches from 1884 to 1896 are now in the possession of the BAA. He is best known as a careful and indefatigable selenographer, and for this work his artistic skill eminently qualified him.

He is most remembered for his book The Moon: A full Description and Map of its Principal Physical Features. Published in 1895, its maps are still highly regarded by lunar observers due to their uncluttered nature.

Elger was member of several astronomical associations, as the Royal Astronomical Society, the short-lived Selenographical Society and the British Astronomical Association. Besides his astronomical work, he was an ardent archaeologist and founded the Bedfordshire Natural History Society and Field Club.

The Lunar crater Elger is named in his honor.

October 26: Lewis Boss

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Lewis Boss

October 26, 1846 - October 12, 1912

Lewis Boss was an American astronomer. He was born in Providence, Rhode Island. In 1870 he graduated from Dartmouth College, then went to work as a clerk for the U.S. Government. He served as an assistant astronomer for a government expedition to survey the U.S-Canadian border. In 1876 he became the director of the Dudley Observatory in Schenectady, New York.

He became editor of the Astronomical Journal in 1909, but responsibility passed to his son, Benjamin Boss, upon his death in 1912. Benjamin continued to edit the journal until 1941.

Lewis Boss is noted for his work in cataloguing the locations and proper motions of stars. He also led an expedition to Chile in 1882 to observe the transit of Venus, and also catalogued information concerning cometary orbits.

In 1910, he published Preliminary General Catalogue of 6188 Stars for the Epoch 1900, a compilation of the proper motions of stars. This catalog was later expanded after his death by his son Benjamin Boss.

His most significant discovery was the calculation of the convergent point of the Hyades star cluster.

Boss was awarded the Gold Medal of the Royal Astronomical Society in 1905.

The Lunar crater Boss is named in his honor.

October 25: Henry Norris Russell

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Henry Norris Russell

October 25, 1877 – February 18, 1957

Henry Norris Russell was an American astronomer who, along with Ejnar Hertzsprung, developed the Hertzsprung-Russell diagram (1910). In 1923, working with Frederick Saunders, he developed Russell-Saunders coupling which is also known as LS coupling.

Russell was born in 1877 in Oyster Bay, New York. He studied astronomy at Princeton University, obtaining his B.A. in 1897 and his doctorate in 1899, studying under Charles Augustus Young. From 1903 to 1905, he worked at the Cambridge Observatory with Arthur Robert Hinks as a research assistant of the Carnegie Institution and came under the strong influence of George Darwin.

He returned to Princeton to become an instructor in astronomy (1905-1908), assistant professor (1908-1911), professor (1911-1927) and research professor (1927-1947). He was also the director of the Princeton University Observatory from 1912 to 1947.

He co-wrote an influential two-volume textbook in 1927 with Raymond Smith Dugan and John Quincy Stewart: Astronomy: A Revision of Young’s Manual of Astronomy (Ginn & Co., Boston, 1926–27, 1938, 1945). This became the standard astronomy textbook for about two decades. There were two volumes: the first was The Solar System and the second was Astrophysics and Stellar Astronomy. The textbook popularized the idea that a star's properties (radius, surface temperature, luminosity, etc.) were largely determined by the star's mass and chemical composition, which became known as the Vogt-Russell theorem (including Hermann Vogt who independently discovered the result). Since a star's chemical composition gradually changes with age (usually in a non-homogeneous fashion), stellar evolution results.

The Lunar crater Russell is named in his honor.

October 24: Wilhelm Eduard Weber

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Wilhelm Eduard Weber

October 24, 1804 – June 23, 1891

Wilhelm Weber was a German physicist and, together with Carl Friedrich Gauss, inventor of the first electromagnetic telegraph.

During 1831, on the recommendation of Carl Friedrich Gauss, he was hired by the University of Göttingen as professor of physics, at the age of twenty-seven. His lectures were interesting, instructive, and suggestive. Weber thought that, in order to thoroughly understand physics and apply it to daily life, mere lectures, though illustrated by experiments, were insufficient, and he encouraged his students to experiment themselves, free of charge, in the college laboratory.

As a student of twenty years he, with his brother, Ernst Heinrich Weber, Professor of Anatomy at Leipzig, had written a book on the Wave Theory and Fluidity, which brought its authors a considerable reputation. Acoustics was a favourite science of his, and he published numerous papers upon it in Poggendorffs Annalen, Schweigger's Jahrbücher für Chemie und Physik, and the musical journal Carcilia. The 'mechanism of walking in mankind' was another study, undertaken in conjunction with his younger brother, Eduard Weber. These important investigations were published between the years 1825 and 1838. Gauss and Weber constructed the first electromagnetic telegraph during 1833, which connected the observatory with the institute for physics in Göttingen.

Dismissed by the Hanoverian Government for his liberal political opinions, Weber travelled for a time, visiting England, among other countries, and became professor of physics in Leipzig from 1843 to 1849, when he was reinstalled at Göttingen. One of his most important works was the Atlas des Erdmagnetismus ("atlas of geomagnetism"), a series of magnetic maps, and it was chiefly through his efforts that magnetic observatories were instituted. He studied magnetism with Gauss, and during 1864 published his Electrodynamic Proportional Measures containing a system of absolute measurements for electric currents, which forms the basis of those in use.

He was elected a foreign member of the Royal Swedish Academy of Sciences during 1855.

The Lunar crater Weber and the SI unit of magnetic flux, the weber (symbol: Wb) are named in his honor. He is also known for first use of 'c' for speed of light.

October 23: Gustav Spörer

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Friederich Wilhelm Gustav Spörer

October 23, 1822 – July 7, 1895

Gustav Spörer was a German astronomer.

He is noted for his studies of sunspots and sunspot cycles. In this regard he is often mentioned together with Edward Maunder. Spörer was the first to note a prolonged period of low sunspot activity from 1645 to 1715. This period is known as the Maunder Minimum.

Spörer was a contemporary of Richard Christopher Carrington, an English astronomer. Carrington is generally credited with discovering Spörer's law, which governs the variation of sunspot latitudes during the course of a solar cycle. Spörer added to Carrington's observations of sunspot drift and is sometimes credited with the discovery.

The Spörer minimum was a period of low sunspot activity from roughly 1420 to 1570.

The Lunar crater Spörer is named in his honor.

October 22: Albert Whitford

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Albert Edward Whitford

October 22, 1905 – March 28, 2002

Albert Whitford was an American astronomer.

Whitford was born in Milton, Wisconsin and attended Milton College. He received his PhD from the University of Wisconsin–Madison. He served as the director of Washburn Observatory from 1948 to 1958. From 1958 to 1968 he was the director of Lick Observatory. Later he served on the faculties of both the University of California, Santa Cruz and the University of Wisconsin–Madison.

Whitford was a pioneer in the field of photoelectric photometry, greatly improving sensitivity. The Whitford reddening curve, quantifying the interstellar absorption of light, was important in the mapping of the distribution of stars in the Milky Way. He also studied the stars in galactic nuclear bulges.

In 1986 Whitford received the Henry Norris Russell Lectureship and in 1996 he was awarded the Bruce Medal.

The asteroid 2301 Whitford is named in his honor.

October 20: Christopher Wren

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Sir Christopher Wren

October 20, 1632 – February 25, 1723

Christopher Wren was one of the best known and highest acclaimed English architects in history, responsible for rebuilding 55 churches in the City of London after the Great Fire in 1666, including his masterpiece St Paul's Cathedral, completed in 1710.

Educated in Latin and Aristotelian physics at the University of Oxford, Wren was a notable astronomer, geometer, mathematician-physicist as well as an architect. He was a founder of the Royal Society (president 1680–82), and his scientific work was highly regarded by Sir Isaac Newton and Blaise Pascal.

One of Wren's friends, another great scientist and architect in his time, Robert Hooke said of him "Since the time of Archimedes there scarce ever met in one man in so great perfection such a mechanical hand and so philosophical mind."

When a fellow of All Souls, Wren constructed a transparent beehive for scientific observation; he began observing the moon, which was to lead to the invention of micrometers for the telescope. He experimented on terrestrial magnetism and had taken part in medical experiments, performing the first successful injection of a substance into the bloodstream (of a dog).

In Gresham College, he did experiments involving determining longitude through magnetic variation and through lunar observation to help with navigation, and helped construct a 35-foot (11 m) telescope with Sir Paul Neile. Wren also studied and improved the microscope and telescope at this time. He had also been making observations of the planet Saturn from around 1652 with the aim of explaining its appearance. His hypothesis was written up in De corpore saturni but before the work was published, Huygens presented his theory of the rings of Saturn. Immediately Wren recognized this as a better hypothesis than his own and De corpore saturni was never published. In addition, he constructed an exquisitely detailed lunar model and presented it to the king.

A year into Wren's appointment as a Savilian Professor in Oxford, the Royal Society was created and Wren became an active member. As a Savilian Professor, Wren studied thoroughly in mechanics, especially in elastic collisions and pendulum motions, which he studied extensively. He also directed his far-ranging intelligence to the study of meteorology, and fabricated a "weather-clock" that recorded temperature, humidity, rainfall and barometric pressure, which could be used to predict the weather.

Another topic to which Wren contributed was optics. He published a description of an engine to create perspective drawings and he discussed the grinding of conical lenses and mirrors. Out of this work came another of Wren's important mathematical results, namely that the hyperboloid of revolution is a ruled surface. These results were published in 1669. In subsequent years, Wren continued with his work with the Royal Society, although after the 1680s his scientific interests seem to have waned: no doubt his architectural and official duties absorbed all his time.

Mentioned above are only a few of Wren’s scientific works. He also studied in other areas not mentioned, ranging from agriculture, ballistics, water and freezing, to investigating light and refraction only to name a few. Thomas Birch's History of the Royal Society is one of the most important sources of our knowledge not only of the origins of the Society, but also the day to day running of the Society. It is in these records that the majority of Wren’s scientific works are recorded.

October 19: Subrahmanyan Chandrasekhar

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Subrahmanyan Chandrasekhar

October 19, 1910 – August 21, 1995

Subrahmanyan Chandrasekhar was an Indian American astrophysicist. He was a Nobel laureate in physics along with William Alfred Fowler for their work in the theoretical structure and evolution of stars. He was the nephew of Indian Nobel Laureate Sir C. V. Raman.

Chandrasekhar served on the University of Chicago faculty from 1937 until his death in 1995 at the age of 84. He became a naturalized citizen of the United States in 1953.

Chandrasekhar (Chandra) was born in Lahore, India (present day Pakistan). Chandra was awarded a Government of India scholarship to pursue graduate studies at the University of Cambridge, where he was admitted to Trinity College and became a research student of Professor R. H. Fowler. On the advice of Prof. P. A. M. Dirac, as part of his graduate studies, Chandra spent a year at the Institut for Teoretisk Fysik in Copenhagen, where he met Prof. Niels Bohr.

In January 1937, Chandrasekhar was recruited to the University of Chicago faculty as Assistant Professor by Dr. Otto Struve and President Robert Maynard Hutchins. He was to remain at the university for his entire career, becoming Morton D. Hull Distinguished Service Professor of Theoretical Astrophysics in 1952 and attaining emeritus status in 1985.

Chandrasekhar developed a style of working continuously in one specific area of physics for a number of years; consequently, his working life can be divided into distinct periods. He studied stellar structure, including the theory of white dwarfs, during the years 1929 to 1939, and subsequently focused on stellar dynamics from 1939 to 1943. Next, he concentrated on the theory of radiative transfer and the quantum theory of the negative ion of hydrogen from 1943 to 1950. This was followed by sustained work on hydrodynamic and hydromagnetic stability from 1950 to 1961. In the 1960s, he studied the equilibrium and the stability of ellipsoidal figures of equilibrium, but also general relativity. During the period, 1971 to 1983 he studied the mathematical theory of black holes, and, finally, during the late 80s, he worked on the theory of colliding gravitational waves.

From 1952 to 1971 Chandrasekhar was editor of the Astrophysical Journal.

During the years 1990 to 1995, Chandrasekhar worked on a project devoted to explaining the detailed geometric arguments in Sir Isaac Newton's Philosophiae Naturalis Principia Mathematica using the language and methods of ordinary calculus. The effort resulted in the book Newton's Principia for the Common Reader, published in 1995. Chandrasekhar was an honorary member of the International Academy of Science.

Chandrasekhar's most famous success was the astrophysical Chandrasekhar limit. The limit describes the maximum mass of a white dwarf star, ~1.44 solar masses, or equivalently, the minimum mass, above which a star will ultimately collapse into a neutron star or black hole (following a supernova). The limit was first calculated by Chandrasekhar in 1930 during his maiden voyage from India to Cambridge, England for his graduate studies.

In 1999, NASA named the third of its four "Great Observatories'" after Chandrasekhar. The Chandra X-ray Observatory was launched and deployed by Space Shuttle Columbia on July 23, 1999.

The asteroid 1958 Chandra is also named after Chandrasekhar.

Chandrasekhar was the mathematics professor of the renowned American astronomer Carl Sagan at the University of Chicago. In his book The Demon-Haunted World Sagan wrote "I discovered what true mathematical elegance is from Subrahmanyan Chandrasekhar."

October 18: Pascual Jordan

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Pascual Jordan

October 18, 1902 - July 31, 1980

Pascual Jordan was a theoretical and mathematical physicist who made significant contributions to quantum mechanics and quantum field theory. He contributed much to the mathematical form of matrix mechanics, and developed canonical anticommutation relations for fermions. While the Jordan algebra he invented is no longer employed in quantum mechanics, it has found other mathematical applications.

Jordan joined the Nazi party and became a brownshirt, a political affiliation which isolated him within the physics community.

Jordan enrolled in the Hanover Technical University in 1921 where he studied an eclectic mix of zoology, mathematics, and physics. As was typical for a German university student of the time, he shifted his studies to another university before obtaining a degree. Göttingen University, his destination in 1923, was then at the very zenith of its prowess and fame in mathematics and the physical sciences. At Göttingen Jordan became an assistant first to mathematician Richard Courant and then to physicist Max Born.

Together with Max Born and Werner Heisenberg he was co-author of an important series of papers on quantum mechanics. He went on to pioneer early quantum field theory before largely switching his focus to cosmology before World War II.

Jordan devised a type of non-associative algebras, now named Jordan algebras in his honor, in an attempt to create an algebra of observables for quantum mechanics and quantum field theory. Today, von Neumann algebras are employed for this purpose. Jordan algebras have since been applied in projective geometry and number theory.

Had Jordan not joined the Nazi party, it is conceivable that he could have shared the 1954 Nobel Prize in Physics awarded to Max Born.

October 17: Peter Nilson

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Peter Nilson

October 17, 1937 – March 8, 1998

Peter Nilson was a Swedish astronomer and novelist. Active at Uppsala University, he compiled a catalogue of galaxies. He was appreciated for a number of essay books (primarily about science) and for a number of science fiction novels like "The Space Guardian."

He was born in a Smålandian village and under the early teens a farmer, but science, with its celebrities such as Charles Darwin and Albert Einstein made such an impression on him, as to motivate him to accomplish college studies by letter correspondence.

In the early 1960's he began his studies in Uppsala University, initially in mathematics, and thereafter theoretical physics, aesthetics, history of ideas and astronomy.

He was elected a member of the Royal Swedish Academy of Sciences in 1993.

October 16: Frederick Eugene Wright

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Dr. Frederick Eugene Wright

October 16, 1877 – August 25, 1953

Frederick Wright was an American optician and geophysicist. He was the second president of the Optical Society of America from 1918-1919.

He was born in Marquette, Michigan, and his father was a state geologist. In 1895 his mother took Frederick and his two brothers to Germany where he would complete his education. He was awarded his Ph.D. summa cum laude from the University of Heidelberg.

After returning to the United States, he taught at the Michigan College of Mines and became the Assistant State Geologist. He moved to Washington D.C. in 1904, joining the United States Geological Survey. He then spent some time in exploration of Alaska. In 1906 he joined the Carnegie Institution as a member of their Geophysical Laboratory. He remained on the staff until his retirement in 1944.

In 1906 he met Kathleen Finley and in 1909 they were married. Their daughter Helen Wright (1914-1997) who became a pioneer in the study of science history.

Among his contributions were studies in the military uses of optical glass; physical study of lunar features based on the properties of the reflected light, and the precambrian geology of the region near Lake Superior. At the time of his death he was considered the foremost authority on the Moon.

Wright was co-author of a major 1963 summary: "The Lunar Surface: Introduction" in The Moon, Meteorites and Comets (Edited by Middlehurst and GP Kuiper). F.E. Wright also was responsible for creating one of the most remarkable - and rare - lunar globes ever. Photographic emulsions were deposited on globes and then telescopic images were projected onto the globes. Some globes were made of glass and had light bulbs within - apparently, they "beautifully and realistically simulate the Moon."

He served as the home secretary of the National Academy of Sciences for two decades. He was a member of the Optical Society of America, and was president for three years. In 1941 he became president of the Mineralogical Society of America. He was also a member of the London Physical Society, a fellow of the American Academy of Arts and Sciences.

The crater Wright on the Moon is co-named for him and two others.

October 13: Peter Barlow

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Peter Barlow

October 13, 1776 – March 1, 1862

Peter Barlow was an English mathematician and physicist.

In 1801, Barlow was appointed assistant mathematics master at the Royal Military Academy, Woolwich, and retained this post until 1847. He contributed articles on mathematics to The Ladies' Diary as well as publishing books such as: An Elementary Investigation of the Theory of Numbers (1811); A New Mathematical and Philosophical Dictionary (1814); and New Mathematical Tables (1814).

The latter became known as Barlow's Tables and gives squares, cubes, square roots, cube roots, and reciprocals of all numbers from 1 to 10,000. These tables were regularly reprinted until 1965, when computers rendered them obsolete. Barlow also contributed largely to the Encyclopaedia Metropolitana.

Barlow made an important contribution to astronomy by inventing the Barlow lens, an achromatic telescope lens in which two glass layers enclosed a colourless liquid (later replaced by a different kind of glass).

In 1823 he was made a fellow of the Royal Society and two years later received its Copley Medal for his work on correcting the deviation in ship compasses caused by the presence of iron in the hull. Some of his magnetic research was done in collaboration with Samuel Hunter Christie. Barlow's Wheel is an early electric motor he invented, while Barlow's law is an (incorrect) law describing electrical conductance.

October 12: Carl August von Steinheil

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Carl August von Steinheil

October 12, 1801 – September 14, 1870

Carl August von Steinheil was a German physicist.

Steinheil was born in Ribeauvillé, Alsace. He studied law in Erlangen then astronomy in Göttingen and Königsberg. He continued his studies in astronomy and physics when he started living on his father's manor in Perlachseck near Munich. He was professor for mathematics and physics at the University of Munich from 1832 to 1849.

In 1839, Steinheil used silver chloride and a cardboard camera to make pictures in negative from the Museum of Art and the Munich Frauenkirche, then taking another picture of the negative to get a positive, the actual black and white reproduction of a view on the object. The round pictures were about four cm wide, the way to get these pictures was called Steinheil method.

In 1846 Steinheil was called to Naples to install a new system for weight and measure units. Three years later, he was in the Board of Telegraphy in the Austrian Trade Ministry, designing a telegraph network for the entire empire, and helped to form the "Deutsch-Österreichischer Telegraphenverein" (German-Austrian Telegraph Society). In 1851 he started the Swiss telegraph network, when he returned to Munich as 'Konservator' of the mathematic-physical collections and ministerial secretary in the Trade Ministry of Bavaria.

He founded the optical-astronomical company C.A. Steinheil und Söhne to build telescopes, spectroscopes and photometers (his invention, used to measure brightness). In 1852 he added refractors and reflectors with silver-covered mirrors to the production. The silvering was done in a process developed by his friend Justus Liebig. Since 1862, his sons continued his company.

The Lunar crater Steinheil is named in his honor.

October 11: Heinrich Olbers

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Heinrich Wilhelm Matthäus Olbers

October 11, 1758 – March 2, 1840

Heinrich Olbers was a German physician and astronomer.

Olbers was born in Arbergen, near Bremen, and studied to be a physician at Göttingen. After his graduation in 1780, he began practicing medicine in Bremen, Germany. At night he dedicated his time to astronomical observation, making the upper story of his home into an observatory. He also devised the first satisfactory method of calculating cometary orbits.

On March 28, 1802, Olbers discovered and named the asteroid Pallas. Five years later, on March 29, 1807, he discovered the asteroid Vesta, which he allowed Carl Friedrich Gauss to name. As the word "asteroid" was not yet coined, the literature of the time referred to these minor planets as planets in their own right. He proposed that the asteroid belt, where these objects lay, was the remnants of a planet that had been destroyed. The current view of most scientists is that tidal effects from the planet Jupiter disrupt the formation of planets in the asteroid belt.

On March 6, 1815, Olbers also discovered a periodic comet, now named after him (formally designated 13P/Olbers).

Olbers' paradox, described by him in 1823 (and then reformulated in 1826), states that the darkness of the night sky conflicts with the supposition of an infinite and eternal static universe.

In 1827, he was elected a foreign member of the Royal Swedish Academy of Sciences.

The crater Olbers on the Moon, the asteroid 1002 Olbersia and a 200-km-diameter dark albedo feature on Vesta's surface are all named in his honor.

October 10: Henry Cavendish

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Henry Cavendish

October 10, 1731 - February 24, 1810

Henry Cavendish, FRS was a British scientist noted for his discovery of hydrogen or what he called "inflammable air". He described the density of inflammable air, which formed water on combustion, in a 1766 paper "On Factitious Airs". Antoine Lavoisier later reproduced Cavendish's experiment and gave the element its name. Cavendish is also known for the Cavendish experiment, his measurement of the Earth's density, and early research into electricity.

Henry Cavendish was born in Nice, France, where his family was living at the time. His mother was Lady Anne Grey, daughter of the Duke of Kent and his father was Lord Charles Cavendish, son of 2nd Duke of Devonshire.

At age 11, Cavendish was a pupil at Peter Newcome's School in Hackney. At age 18 he entered the University of Cambridge in St Peter's College, now known as Peterhouse, but left four years later without graduating. His first paper, "Factitious Airs", appeared thirteen years later, in 1766.

Cavendish was silent, and solitary, viewed as somewhat eccentric, he only spoke to his female servents by notes and formed no close personal relationships outside his family. By one account, Cavendish had a back staircase added to his house in order to avoid encountering his housekeeper because he was especially shy of women.

Because of his asocial and secretive behaviour, Cavendish often avoided publishing his work, and much of his findings were not even told to his fellow scientists. In the late nineteenth century, long after his death, James Clerk Maxwell looked through Cavendish's papers and found things for which others had been given credit. Examples of what was included in Cavendish's discoveries or anticipations were Richter's Law of Reciprocal Proportions, Ohm's Law, Dalton's Law of Partial Pressures, principles of electrical conductivity (including Coulomb's Law), and Charles's Law of Gases.

In addition to his achievements in chemistry, Cavendish is also known for the Cavendish experiment, the first to measure the force of gravity between masses in a laboratory and to produce an accurate value for the Earth's density. His work led others to accurate values for the gravitational constant (G) and the Earth's mass.

The Lunar crater Cavendish is named in his honor.

October 9: Karl Schwarzschild

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Karl Schwarzschild

October 9, 1873 – May 11, 1916

Karl Schwarzschild was a German physicist. He is also the father of astrophysicist Martin Schwarzschild.

He is best known for providing the first exact solution to the Einstein field equations of general relativity, for the limited case of a single spherical non-rotating mass, which he accomplished in 1915, the same year that Einstein first introduced general relativity. The Schwarzschild solution, which makes use of Schwarzschild coordinates and the Schwarzschild metric, leads to the well-known Schwarzschild radius, which is the size of the event horizon of a non-rotating black hole.

Schwarzschild was born in Frankfurt am Main. He was something of a child prodigy, having a paper on celestial mechanics published when he was only sixteen. He studied at Strasbourg and Munich, obtaining his doctorate in 1896 for a work on Jules Henri Poincaré's theories.

From 1897, he worked as assistant at the Kuffner observatory in Vienna. From 1901 until 1909 he was a professor at the prestigious institute at Göttingen, where he had the opportunity to work with some significant figures including David Hilbert and Hermann Minkowski. Schwarzschild became the director of the observatory in Göttingen. He moved to a post at the Astrophysical Observatory in Potsdam in 1909.

From 1912, Schwarzschild was a member of the Prussian Academy of Sciences.

While serving on the front in Russia in 1915, he began to suffer from a rare and painful skin disease called pemphigus. Nevertheless, he managed to write three outstanding papers, two on relativity theory and one on quantum theory. His papers on relativity produced the first exact solutions to the Einstein field equations, and a minor modification of these results gives the well-known solution that now bears his name: the Schwarzschild metric.

Thousands of dissertations, articles, and books have since been devoted to the study of Schwarzschild's solutions to the Einstein field equations. However, although Schwarzschild's best known work lies in the area of general relativity, his research interests were extremely broad, including work in celestial mechanics, observational stellar photometry, quantum mechanics, instrumental astronomy, stellar structure, stellar statistics, Halley's comet, and spectroscopy.

Some of his particular achievements include measurements of variable stars, using photography, and the improvement of optical systems, through the perturbative investigation of geometrical aberrations.

The Lunar crater Schwarzschild, the Karl Schwarzschild Medal, the Karl Schwarzschild Observatory and more are named in his honor.

October 8: Ejnar Hertzsprung

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Ejnar Hertzsprung

October 8, 1873 - October 21, 1967

Ejnar Hertzsprung was a Danish chemist and astronomer.

In the period 1911-1913, together with Henry Norris Russell, he developed the Hertzsprung-Russell diagram.

In 1913 he determined the distances to several Cepheid variable stars by statistical parallax, and was thus able to calibrate the relationship discovered by Henrietta Leavitt between Cepheid period and luminosity. In this determination he made a mistake, possibly a slip of the pen, putting the stars 10 times too close. He used this relationship to estimate the distance to the Small Magellanic Cloud.

From 1919 to 1946 Hertzsprung worked at Leiden Observatory in The Netherlands, from 1937 as director. Perhaps his greatest contribution to astronomy was the development of a classification system for stars to divide them by spectral type, stage in their development, and luminosity. The "Hertzsprung-Russell Diagram" was used for many years as a classification system to explain stellar types and evolution.

He discovered two asteroids, 1627 Ivar (25 September 1929) and 1702 Kalahari (7 July 1924)

Hertzsprung received the Gold Medal of the Royal Astronomical Society in 1929 and the Bruce Medal in 1937.

The Lunar crater Hertzsprung and the asteroid 1693 Hertzsprung are named in his honor.

October 7: James Edwin Webb

2009-10-07T00:05:00.001-04:00

James Edwin Webb

October 7, 1906 – March 27, 1992

James Webb was the second administrator of NASA, serving from 14 February 1961 to 7 October 1968.

Webb oversaw NASA from the beginning of the Kennedy administration through the end of the Johnson administration, thus overseeing all the critical first manned launches in the Mercury through Gemini programs, until just before the first manned Apollo flight. He also dealt with the Apollo 1 fire.

The planned scientific probe (launch now scheduled 2014) originally called the Next Generation Space Telescope (NGST) was renamed in 2002 as the James Webb Space Telescope to honor Webb's memory.

Webb went to Washington in 1961 when he accepted the position of the Administrator of NASA. Under his direction, the agency undertook to achieve the goal set by President John F. Kennedy of landing an American on the Moon before the end of the decade of the 1960s through the success of the Apollo program. For seven years after President Kennedy's May 25, 1961, announcement of the goal of a manned lunar landing, through October 1968, Webb endeavored for support for NASA in Congress. As a longtime Washington insider, and with the backing of President Lyndon B. Johnson, he was able to acquire continued support for and resources to accomplish the Apollo Moon landing on the schedule President Kennedy had announced.

During his administration, NASA developed from a loose collection of research centers into a coordinated organization. Webb had a key role in creating the Manned Spacecraft Center, later, the Johnson Space Center, near Houston, Texas. Despite the pressures to focus on the Apollo program, Webb ensured that NASA carried out a meaningful program of planetary exploration with the Mariner and Pioneer space probe programs.

Webb was in the leadership of NASA during the Apollo 1 accident in 1967. Webb told the media at the time,

"We've always known that something like this was going to happen sooner or later. ... Who would have thought that the first tragedy would be on the ground?"

Webb went to President Johnson and asked that NASA be allowed to handle the accident investigation, and to direct its recovery from the accident. He promised to be truthful in assessing blame, and he pledged to assign that to himself and NASA management, as appropriate. The agency set out to discover the details of the tragedy, to correct problems, and to continue its progress to the Apollo 11 lunar landing.

Webb reported his investigation's findings to various Congressional committees, and he took a personal grilling at nearly every meeting. Whether by happenstance or by design, Webb managed to deflect some of the backlash over the accident away from both NASA as an agency and from the Johnson administration. As a result, NASA's image and popular support were largely undamaged.

However, Webb was a Democrat tied closely to Johnson, and, with Johnson choosing not to run for reelection, decided to step down as administrator as this would allow the next president to choose his own administrator.

NASA's planned James Webb Space Telescope was renamed in Webb's honor in 2002. The telescope is referred to as "the Hubble successor".

October 6: Meghnad Saha

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Meghnad Saha

October 6, 1893 – February 16, 1956

Meghnad Saha was an Indian astrophysicist best known for his development of the Saha equation, used to describe chemical and physical conditions in stars.

Saha was a professor at Allahabad University from 1923 to 1938, and thereafter a professor and Dean of the Faculty of Science at the University of Calcutta until his death in 1956. He became Fellow of the Royal Society in 1927. He was president of the 21st session of the Indian Science Congress in 1934.

Saha was fortunate to have brilliant teachers and class fellows. In his student days, Jagadish Chandra Bose and Prafulla Chandra Roy were at the pinnacle of their fame. Amongst his class fellows were Satyendra Nath Bose, Jnan Ghosh and J. N. Mukherjee. In later life he was close to Amiya Charan Banerjee, a renowned mathematician at Allahabad University.

Meghnad Saha's best-known work concerned the thermal ionisation of elements, and it led him to formulate what is known as the Saha equation. This equation is one of the basic tools for interpretation of the spectra of stars in astrophysics. By studying the spectra of various stars, one can find their temperature and from that, using Saha's equation, determine the ionisation state of the various elements making up the star.

Saha also helped to build several scientific institutions, such as the Physics Department in Allahabad University and the Institute of Nuclear Physics in Calcutta. He founded the journal Science and Culture and was the editor until his death. He was the leading spirit in organizing several scientific societies, such as the National Academy of Science (1930), the Indian Physical Society (1934), Indian Institute of Science (1935) and the Indian Association for the Cultivation of Science (1944). A lasting memorial to him is the Saha Institute of Nuclear Physics, founded in 1943 in Kolkata.

He also invented an instrument to measure the weight and pressure of solar rays.

"The impetus given to astrophysics by Saha’s work can scarcely be overestimated, as nearly all later progress in this field has been influenced by it and much of the subsequent work has the character of refinements of Saha’s ideas." - S. Rosseland

The Lunar crater Saha is named in his honor.

October 5: Robert Goddard

2009-10-05T00:05:00.001-04:00

Robert Hutchings Goddard

October 5, 1882 – August 10, 1945

Robert Goddard, U.S. professor of physics and scientist, was a pioneer of controlled, liquid-fueled rocketry. He launched the world's first liquid-fueled rocket on March 16, 1926. From 1930 to 1935, he launched rockets that attained speeds of up to 885 km/h (550 mph). Though his work in the field was revolutionary, he was sometimes ridiculed for his theories.

Goddard received little scientific support during his lifetime. Eventually, however, he became recognized — along with Tsiolkovsky and Oberth — as one of the fathers of modern rocketry. He was the first not only to recognize the scientific potential behind missiles and space travel but also to bring about the physical design and construction of those ideas.

In 1919, the Smithsonian Institution published Goddard's groundbreaking work, A Method of Reaching Extreme Altitudes. The report describes Goddard's mathematical theories of rocket flight, his experiments with solid-fuel rockets, and the possibilities he saw of exploring the earth's atmosphere and beyond. Along with Konstantin Tsiolkovsky's earlier work, The Exploration of Cosmic Space by Means of Reaction Devices (1903), Goddard's little book is regarded as one of the pioneering works of the science of rocketry. It was distributed worldwide and is believed to have influenced the work of subsequent pioneers such as Hermann Oberth and Wernher von Braun in Germany and Sergey Korolev in the USSR.

Goddard began experimenting with liquid oxygen and liquid-fueled rockets in September 1921, and bench tested the first liquid-fueled engine in November 1923. It had a cylindrical combustion chamber, using impinging jets to mix and atomize liquid oxygen and gasoline.

He launched the first liquid-fueled rocket on March 16, 1926 in Auburn, Massachusetts. His journal entry of the event was notable for its laconic understatement: "The first flight with a rocket using liquid propellants was made yesterday at Aunt Effie's farm." The rocket, which was dubbed "Nell", rose just 41 feet during a 2.5-second flight that ended in a cabbage field, but it was an important demonstration that liquid propellants were possible. The launch site is now a National Historic Landmark, the Goddard Rocket Launching Site.

Goddard was awarded 214 patents for his work, 83 of which came during his lifetime.

The Goddard Space Flight Center was established in 1959. The crater Goddard on the Moon is also named in his honor.

October 4: Christen Longomontanus

2009-10-04T00:05:00.004-04:00

Christen Sørensen Longomontanus

October 4, 1562 – October 8, 1647

Christen Longomontanus (or Longberg), was a Danish astronomer.

The name Longomontanus was a Latinized form of the name of the village of Lomborg, Jutland, Denmark, where he was born. Engaged by Tycho Brahe in 1589 as his assistant in his great astronomical observatory of Uraniborg, he rendered invaluable service for eight years. Having left the island of Hven with his master, he obtained his discharge at Copenhagen on June 1, 1597, in order to study at some German universities. He rejoined Tycho at Prague in January 1600, and having completed the Tychonic lunar theory, turned homeward again in August.

Longomontanus was not an advanced thinker. He adhered to Tycho's erroneous views about refraction, believed that comets were messengers of evil, and imagined that he had squared the circle. He inaugurated, at Copenhagen in 1632, the erection of a stately astronomical tower, but did not live to witness its completion. King Christian IV of Denmark, to whom he dedicated his Astronomia Danica, an exposition of the Tychonic system of the world, conferred upon him the canonry of Lunden in Schleswig.

However, it was Longomontanus who really developed Tycho's geoheliocentric model empirically and publicly to common acceptance in the 17th century in his 1622 astronomical tables. When Tycho died in 1601, his program for the restoration of astronomy was unfinished. The observational aspects were complete, but two important tasks remained, namely the selection and integration of the data into accounts of the motions of the planets, and the presentation of the results on the entire program in the form of a systematic treatise. Longomontanus, Tycho's sole disciple, assumed the responsibility and fulfilled both tasks in his voluminous Astronomia Danica (1622).

Regarded as the testament of Tycho, the work was eagerly received in seventeenth-century astronomical literature. But unlike Tycho's, his geoheliocentric model gave the Earth a daily rotation as in the models of Ursus and Roslin, and which is sometimes called the 'semi-Tychonic' system. As an indication of his book's popularity and of the semi-Tychonic system, it was reprinted in 1640 and 1663. Having originally worked on calculating the Martian orbit for Tycho with Kepler, he had already modelled its orbit to within 2 arcminutes error in his geoheliocentric model when Kepler had still only achieved 8 arcminutes in his heliocentric system.

The Lunar crater Longomontanus is named in his honor.

October 3: Hervé Faye

2009-10-03T00:05:00.001-04:00

Hervé Auguste Étienne Albans Faye

October 3, 1814 – July 4, 1902

Hervé Faye was a French astronomer, born at Saint-Benoît-du-Sault and educated at the Ecole Polytechnique, which he left in 1834, before completing his course, to accept a position in the Paris Observatory to which he had been appointed on the recommendation of M. Arago.

He studied comets, and discovered the periodic comet 4P/Faye on November 22, 1843. His discovery of "Faye's comet" attracted worldwide attention, and won him the Lalande prize and a membership in the Academy of Sciences. In 1848 he became an instructor in geodesy at the Polytechnique, and in 1854 rector of the academy at Nancy and professor of astronomy in the faculty of science there. Other promotions followed in succeeding decades. He became Minister of Public Instruction in the Rochebouet cabinet in 1877, a position which he held only briefly.

His work covered the entire field of astronomical investigation. It comprised the determination of comet periods, the measurement of parallaxes, and the study of stellar and planetary movements. He also studied the physics of the sun. He advanced several original theories on the nature and form of comets, meteors, the aurora borealis, and the sun.

In collaboration with Charles Galusky he translated Humboldt's Cosmos (four volumes, 1846-59), and, in addition to numerous contributions to scientific periodicals, published many important works.

The Lunar crate Faye is named in his honor.

October 2: Charles Stark Draper

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Charles Stark Draper

October 2, 1901 – July 25, 1987

Charles Draper was an American scientist and engineer, often referred to as "the father of inertial navigation." He was the founder and director of the MIT Instrumentation Laboratory, later renamed the Charles Stark Draper Laboratory, which under his direction designed and built the Apollo Guidance Computer for NASA, which made the Apollo moon landings possible.

Born in Windsor, Missouri, he attended the University of Missouri in 1917, then transferred to Stanford University, California in 1919, from which he earned a B.A. in psychology in 1922. After Stanford, he attended Massachusetts Institute of Technology (MIT), from which he earned an S.B. in electrochemical engineering in 1926, and an S.M. and Sc.D. in physics in 1928 and 1938 respectively.

He started teaching while at MIT, first as an assistant, then quickly became a full professor in aeronautical engineering in 1939. It was here that he founded the Instrumentation Laboratory in the 1930s, later spun off as The Charles Stark Draper Laboratory, Inc. In 1961, Draper and the Instrumentation Lab were awarded the first contract given out for the Apollo program to send humans to the moon, which had just been announced by President John F. Kennedy. This led to the creation of the Apollo Guidance Computer, a one-cubic-foot computer that controlled the navigation and guidance of the Lunar Excursion Module to the surface of the moon during six successful landings.

Draper invented and developed inertial navigation, a technology used in aircraft, space vehicles, and submarines which allows such vehicles to navigate by sensing changes in direction, using gyroscopes, and speed, using accelerometers. A pioneering figure in the aircraft engineering field, he also contributed to the Apollo space program with his knowledge of guidance systems. For his inventions and contributions, Draper was inducted to the National Inventors Hall of Fame in 1981.

The Charles Stark Draper Prize is a prominent prize in engineering devoted to the memory of Charles Stark Draper.

October 1: Charles Edward Adams

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Dr Charles Edward Adams (left) reading an anemometer.

Charles Edward Adams

October 1, 1870 - October 31, 1945

Charles Edward Adams was a University lecturer, surveyor, astronomer and seismologist. He was born at Lawrence, Otago, New Zealand.

Adams was awarded an MSc from the University of New Zealand in 1909 and by 1910 was chief computer at the head office of the Lands and Survey Department. The techniques he devised during this period for the prediction of tides were, with few modifications, employed in New Zealand until 1924. In 1911, while continuing to discharge his duties in the department, he was appointed astronomical observer at Wellington. Early the following year he became government astronomer. He spent 1915 as Martin Kellogg fellow at the Lick Observatory, California, then returned to a full-time position as government astronomer in the Internal Affairs Department. He was awarded a DSc from the University of New Zealand in 1915 for a thesis entitled Harmonic analysis of tidal observations and predictions of tides.

It was Adams's work in astronomy that identifies him as one of New Zealand's important scientists. He developed methods of computation of planetary ephemerides and cometary orbits and made observations of sunspots, variable stars, planets and auroras. In 1922 he accompanied the Lick Observatory solar eclipse expedition to Western Australia and in 1930 led an eclipse expedition to Niuafo'ou, in the Tongan group. He pioneered the use of cinematography for astronomical timing. The camera he devised for photographing the Moon against its background stars, so that accurate longitudes and lunar positions could be gauged, forms the basis of the standard modern instrument.

As government astronomer Adams was in charge of the Hector Observatory and responsible for maintaining accurate time for scientific and civil purposes such as navigation.

He was the founder and president of the New Zealand Astronomical Society (now the Royal Astronomical Society of New Zealand), an associate in astronomy at Yale University and a fellow of the Royal Astronomical Society, London. He was also very active in the establishment of the Carter Observatory, believing that the capital city was entitled to an up-to-date observatory and telescope.

An asteroid discovered in 1985 by astronomers at the Mt John University Observatory, Lake Tekapo, was named 3305 Ceadams in his honour.

Source:

Smith, Warwick D. 'Adams, Charles Edward 1870 - 1945'. Dictionary of New Zealand Biography, updated 22 June 2007

http://www.dnzb.govt.nz/

September 30: Michael Maestlin

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Michael Maestlin

September 30, 1550 - October 20, 1631

Michael Maestlin was a German astronomer and mathematician, known for being the mentor of Johannes Kepler.

Maestlin studied theology, mathematics, and astronomy at the Tübinger Stift in Tübingen, a town in Württemberg. In 1580 he became a Professor of mathematics, first at the University of Heidelberg, then at the University of Tübingen were he taught for 47 years from 1583. In 1582 Maestlin wrote a popular introduction to astronomy.

Among his students was Johannes Kepler (1571-1630). Although he primarily taught the traditional geocentric Ptolemaic view of the solar system, Maestlin was also one of the first to accept and teach the heliocentric Copernican view. Maestlin corresponded with Kepler frequently and played a sizable part in his adoption of the Copernican system. Galileo Galilei's adoption of heliocentrism was also attributed to Maestlin .

The first known calculation of the (inverse) golden ratio as a decimal of "about 0.6180340" was written in 1597 by Maestlin in a letter to Kepler.

Maestlin catalogued the Pleiades cluster on December 24, 1579. Eleven stars in the cluster were recorded by Maestlin, and possibly as many as fourteen were observed. He also observed the occultation of Mars by Venus on October 3, 1590, at Heidelberg.

In Jules Verne's Cinq semaines en ballon (Five Weeks in a Balloon) the character of Joe, the manservant, is described as enjoying, "in common with Moestlin, Kepler's professor, the rare faculty of distinguishing the satellites of Jupiter with the naked eye, and of counting fourteen of the stars in the group of Pleiades, the remotest of them being only of the ninth magnitude."

The Lunar crater Maestlin, the Lunar rille Rimae Maestlin and the asteroid 11771 Maestlin, discovered in 1973, are named in his honor.

September 29: Gustav Mie

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Gustav Adolf Feodor Wilhelm Ludwig Mie

September 29, 1869 – February 13, 1957

Gustav Mie was a German physicist.

Mie was born in Rostock. From 1886 he studied mathematics and physics at the University of Rostock. In addition to his major subjects, he also attended lectures in chemistry, zoology, geology, mineralogy, astronomy as well as logic and metaphysics. In 1889 he continued his studies at the University of Heidelberg and received a doctorate degree in mathematics at the age of 22.

In 1897 he got his Habilitation at the University of Göttingen in theoretical physics and in 1902 became extraordinary professor for theoretical physics at the University of Greifswald. In 1917 he became full professor for experimental physics at Martin Luther University of Halle-Wittenberg. In 1924 he became Professor at the University of Freiburg, where he worked up to his retirement in 1935.

During his Greifswald years he worked on the computation of scattering of an electromagnetic wave by a homogeneous dielectric sphere, which was published in 1908 under the title of “Contributions to the optics of turbid media, particularly of colloidal metal solutions” in Annalen der Physik. The term Mie scattering is still related to his name. Using Maxwell's electromagnetic theory applied to spherical Gold particles Gustav Mie provided a theoretical treatment of plasmon resonance absorption of Gold colloids. The sharp absorption bands depend on the particle size and explain the change in colour that occurs as the size of the colloid nanoparticles is increased from 20 to 1600 nm. He wrote further important contributions to electromagnetism and also to relativity theory.

In addition he was employed on measurements units and finally developed his Mie system of units in 1910 with the basic units Volt, Ampere, Coulomb and Second (VACS-system).

A crater on Mars was named in his honor and a building of the University of Freiburg carries his name.

September 28: Ismaël Bullialdus

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Ismaël Bullialdus

September 28, 1605 - November 25, 1694

Ismaël Bullialdus was a French astronomer. He was born Ismaël Boulliau in Loudun, Vienne, France, the first surviving son to Ismaël Boulliau, a notary by profession and amateur astronomer.

Bullialdus was a friend of Pierre Gassendi, Christiaan Huygens, Marin Mersenne, and Blaise Pascal, and an active supporter of Galileo Galilei and Nicolaus Copernicus. It is for his astronomical and mathematical works that he is best known. Chief among them is his Astronomia philolaica, (published 1645). In this work he strongly supported Kepler's hypothesis that the planets travel in elliptical orbits around the Sun, but argued against the physical theory the latter had proposed to explain them. In particular, he objected to Kepler's proposal that the strength of the force exerted on the planets by the Sun would decrease in inverse proportion to their distance from it. He argued that if such a force existed it would instead have to follow an inverse-square law:

As for the power by which the Sun seizes or holds the planets, and which, being corporeal, functions in the manner of hands, it is emitted in straight lines throughout the whole extent of the world, and like the species of the Sun, it turns with the body of the Sun; now, seeing that it is corporeal, it becomes weaker and attenuated at a greater distance or interval, and the ratio of its decrease in strength is the same as in the case of light, namely, the duplicate proportion, but inversely, of the distances that is, 1/d².

However, Bullialdus did not believe that any such force did in fact exist. After writing the above-quoted passage, he then went on to write:

... I say that the Sun is moved by its own form around its axis, by which form it was ignited and made light, indeed I say that no kind of motion presses upon the remaining planets ... indeed [I say] that the individual planets are driven round by individual forms with which they were provided ...

In his Principia Mathematica of 1687, Isaac Newton acknowledged that Bullialdus's determination of the sizes of the planets' orbits ranked with Kepler's as the most accurate then available.

Bullialdus was one of the earliest members of the Royal Society, London, having been elected on April 4, 1667, seven years after its founding.

The Lunar crater Bullialdus is named in his honor.

September 27: Martin Ryle

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Martin Ryle

September 27, 1918 - October 14, 1984

Sir Martin Ryle was an English radio astronomer who developed revolutionary radio telescope systems (e.g. aperture synthesis) and used them for accurate location and imaging of weak radio sources. In 1946 Ryle and Vonberg were the first people to publish interferometric astronomical measurements at radio wavelengths, although it is claimed that Joseph Pawsey from the University of Sydney had actually made interferometric measurements earlier in the same year. With improved equipment, Ryle observed the most distant known galaxies in the universe at that time. He was the first Professor of Radio Astronomy at the University of Cambridge, and founding director of the Mullard Radio Astronomy Observatory. He was Astronomer Royal from 1972 to 1982.

Ryle and Antony Hewish shared the Nobel Prize for Physics in 1974, the first Nobel prize awarded in recognition of astronomical research.

The focus of early work in Cambridge was on radio waves from the Sun. Ryle's interest quickly shifted to other areas, however, and to explore those he decided early on that the Cambridge group should develop new observing techniques. As a result, Ryle was the driving force in the creation and improvement of astronomical interferometry and aperture synthesis, which have contributed immensely to upgrading the quality of radio astronomical data. In 1946 he built the first multi-element astronomical radio interferometer.

He guided the Cambridge radio astronomy group in the production of several important radio source catalogues. For example, the Third Cambridge Catalogue of Radio Sources (3C) 1959 helped lead to the discovery of the first quasi-stellar object (quasar).

While serving as university lecturer in physics at Cambridge from 1948 to 1959, Ryle became director of the Mullard Radio Astronomy Observatory 1957, and professor of radio astronomy in 1959. He was elected a fellow of the Royal Society in 1952, was knighted in 1966, and succeeded Sir Richard Woolley as Astronomer Royal (1972-82).

Martin Ryle was undoubtedly one of the great astronomers of the 20th Century. He was sometimes considered difficult to work with - in fact he often worked in an office at the Mullard Radio Astronomy Observatory to avoid disturbances from other members of the Cavendish Laboratory and to avoid getting into heated arguments, as Ryle had a hot temper. Ryle worried that Cambridge would lose its standing in the radio astronomy community as other radio astronomy groups had much better funding, so he encouraged a certain amount of secrecy about his aperture synthesis methods in order to keep an advantage for the Cambridge group.

Ryle received the Hughes Medal (1954), the Gold Medal of the Royal Astronomical Society (1964), the Henry Draper Medal (1965), the Royal Medal (1973), the Bruce Medal (1974), and the Nobel Prize in Physics (1974). The Ryle Telescope at Mullard Radio Astronomy Observatory is named in his honor.

September 26: Christopher Hansteen

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Christopher Hansteen

September 26, 1784 – April 11, 1873

Christopher Hansteen was a Norwegian geophysicist, astronomer and physicist.

In 1807 Hansteen began the inquiries in terrestrial magnetism with which his name is especially associated. His first scientific publication was printed in Journal de Physique, following a contest on magnetic axes created in 1811 by the Royal Danish Academy of Sciences and Letters. In 1813 he was given a research scholarship by the recently established (in 1811) Royal Frederick University in Christiania, with a promise of a future academic position.

Working as a lecturer from 1814, in 1816 Hansteen was promoted to professor of astronomy and applied mathematics. He was the editor of the official Norwegian almanac from 1815, manager of the city astronomical observatory from the same year and co-director of the Norwegian Mapping and Cadastre Authority from 1817. In 1819 he published a volume of researches on terrestrial magnetism, which was translated into German under the title of Untersuchungen über den Magnetismus der Erde, with a supplement containing Beobachtungen der Abweichung und Neigung der Magnetnadel and an atlas. By the rules there framed for the observation of magnetical phenomena Hansteen hoped to accumulate analyses for determining the number and position of the magnetic poles of the Earth. In 1822 he co-founded Norway's first journal on natural sciences, Magazin for Naturvidenskaberne. He sat as editor-in-chief for eight years.

In the course of his research he travelled over Finland and the greater part of his own country; and from 1828 to 1830 he undertook, in company with Georg Adolf Erman and with the cooperation of Russia, a government-funded mission to Western Siberia. Shortly after the return of the mission, in 1833 Hansteen moved with his family into the observatory, which was created from drawings by the architect Christian Heinrich Grosch. A magnetic observatory was added in 1839.

From 1835 to 1838 he published textbooks on geometry and mechanics, largely a reaction to his former research assistant Bernt Michael Holmboe's textbooks. In 1842 Hansteen wrote his Disquisitiones de mutationibus, quas patitur momentum acus magneticae. He also contributed various papers to different scientific journals, especially Magazin for Naturvidenskaberne.

Hansteen was a member of the Royal Norwegian Society of Sciences and Letters from 1818 and of the Norwegian Academy of Science and Letters from 1857, as well as several learned societies in other countries, including the Royal Swedish Academy of Sciences (1822). He was a member of the board of the Royal Norwegian Society for Development for many years, and also chaired the board of the Norwegian National Academy of Craft and Art Industry.

The crater Hansteen and the mountain Mons Hansteen on the Moon are named in his honor.

September 25: Ole Rømer

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Ole Christensen Rømer

September 25, 1644 – September 19, 1710

Ole Rømer was a Danish astronomer who in 1676 made the first quantitative measurements of the speed of light.

Ole Rømer went to the University of Copenhagen in 1662, at which his mentor was Rasmus Bartholin. Rømer was given every opportunity to learn mathematics and astronomy using Tycho Brahe's astronomical observations, as Bartholin had been given the task of preparing them for publication.

After studies in Copenhagen, Rømer joined the observatory of Uraniborg on the island of Hven, near Copenhagen, in 1671. Over a period of several months, Jean Picard and Rømer observed about 140 eclipses of Jupiter's moon Io, while in Paris Giovanni Domenico Cassini observed the same eclipses. By comparing the times of the eclipses, the difference in longitude of Paris to Uranienborg was calculated.

Cassini had observed the moons of Jupiter between 1666 and 1668, and discovered discrepancies in his measurements that, at first, he attributed to light having a finite speed. In 1672 Rømer went to Paris and continued observing the satellites of Jupiter as Cassini's assistant. Rømer added his own observations to Cassini's and observed that times between eclipses (particularly those of Io) got shorter as Earth approached Jupiter, and longer as Earth moved farther away. Cassini published a short paper in August 1675 where he states: This second inequality appears to be due to light taking some time to reach us from the satellite; light seems to take about ten to eleven minutes to cross a distance equal to the half-diameter of the terrestrial orbit.

Oddly, Cassini seems to have abandoned this reasoning, which Rømer adopted and set about buttressing in an irrefutable manner, using a selected number of observations performed by Picard and himself between 1671 and 1677. Rømer presented his results to the French Academy of Sciences, and it was summarised soon after by an anonymous reporter in a short paper, Démonstration touchant le mouvement de la lumière trouvé par M. Roemer de l'Académie des sciences, published 7 December 1676 in the Journal des sçavans. Unfortunately the paper bears the stamp of the reporter failing to understand Rømer's presentation, and as the reporter resorted to cryptic phrasings to hide his lack of understanding, he obfuscated Rømer's reasoning in the process. Unfortunately Rømer himself never published his results.

Rømer never gave a value for the speed of light. However, many others calculated a speed from his data, the first being Christiaan Huygens; after corresponding with Rømer and eliciting more data.

Rømer's view that the velocity of light was finite was not fully accepted until measurements of the so-called aberration of light were made by James Bradley in 1727.

In 1809, again making use of observations of Io, but this time with the benefit of more than a century of increasingly precise observations, the astronomer Jean Baptiste Joseph Delambre reported the time for light to travel from the Sun to the Earth as 8 minutes and 12 seconds. Depending on the value assumed for the astronomical unit, this yields the speed of light as just a little more than 300,000 kilometres per second.

A plaque at the Observatory of Paris, where the Danish astronomer happened to be working, commemorates what was, in effect, the first measurement of a universal quantity made on this planet.

The Lunar crater Römer is named in his honor.

September 24: Charlotte Sitterly

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Charlotte Emma Moore Sitterly

September 24, 1898 – March 3, 1990

Charlotte Moore Sitterly was an American astronomer.

Charlotte Moore was born in Ercildoun, Pennsylvania. She graduated from Swarthmore College in 1920 and went on to Princeton to assist Henry Norris Russell. During this time she worked at the Princeton University Observatory and the Mt. Wilson Observatory. She worked extensively on solar spectroscopy, analyzing the spectral lines of the Sun and thereby identifying the chemical elements in the Sun. She earned a Ph.D. in astronomy in 1931 from the University of California, Berkeley on a Lick Fellowship, and then returned to Princeton.

During her second stay at Princeton, she met and married Bancroft W. Sitterly, who became a physics professor. She joined the then National Bureau of Standards (NBS) in 1945. Her tables of atomic spectra and energy levels, published by NBS, have remained essential references in spectroscopy for decades.

Later in her life, it became possible to launch instruments on rockets and she extended her work to the ultraviolet spectral lines.

Sitterly was given the Annie J. Cannon Award (1937), the William F. Meggers Award of the Optical Society of America (1972) and the Bruce Medal (1990).

The asteroid 2110 Moore-Sitterly is named in her honor.

September 23: Johann Encke

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Johann Franz Encke

September 23, 1791 – August 26, 1865

Johann Franz Encke was a German astronomer, born in Hamburg. He is sometimes confused with Karl Ludwig Hencke, another German astronomer.

Encke studied mathematics and astronomy from 1811 at the University of Göttingen under Carl Friedrich Gauss; but he enlisted in the Hanseatic Legion for the campaign of 1813–1814, and became lieutenant of artillery in the Prussian army in 1815. Having returned to Göttingen in 1816, he was at once appointed by Bernhardt von Lindenau as his assistant in the observatory of Seeberg near Gotha.

There he completed his investigation of the comet of 1680, for which the Cotta prize was awarded to him in 1817; he correctly assigned a period of 71 years to the comet of 1812. That comet is now called 12P/Pons-Brooks.

Following a suggestion by Jean-Louis Pons, who suspected one of the three comets discovered in 1818 to be the same one already discovered by him in 1805, Encke began to calculate the orbital elements of this comet. At this time, all the known comets only had an orbital period of seventy years and more, where the aphelion is far beyond the orbit of Uranus. The most famous comet of this family was Comet Halley with its period of seventy-six years. Therefore the orbit of the comet discovered by Pons was a sensation, because his orbit was found to have a period of 3.3 years, therefore the aphelion had to be within the orbit of Jupiter. Encke predicted its return for 1822, but this return was only observable from the southern hemisphere and was seen by Carl Ludwig Christian Rümker from Australia. The comet was also identified with the one seen by Pierre Méchain in 1786 and by Caroline Herschel in 1795.

Encke sent his calculations as a note to Gauss, Olbers, and Bessel. His former mathematics professor published this note and Encke became famous as the discoverer of the short periodic comets. The first object of this family, the Encke comet, was named after him and so it is one of the few comets not named after the discoverer, but after the one who calculated the orbit. Later this comet was identified as the origin of the Taurids meteor showers.

The importance of the predicted return based on the calculation by Encke was rewarded by the Royal Astronomical Society in London by presenting their Gold Medal to him in 1824.

In 1837, Encke described a broad variation in the brightness of the A Ring of Saturn. The Encke Division was later named in honor of his observations of Saturn's rings.

Twice, in 1824 and 1830, he received the Gold Medal of the Royal Astronomical Society.

The crater Encke on the Moon, the asteroid 9134 Encke and the Encke gap of Saturn's rings are named in his honor.

September 22: Pehr Wargentin

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Pehr Wilhelm Wargentin

September 22, 1717 – December 13, 1783

Pehr Wargentin was a Swedish astronomer.

When Pehr Wargentin was 12 years old he observed a (total) lunar eclipse which would spark his life-long interest in Astronomy. During his tenure at Frösö trivialskola (elementary school), his teacher deemed him advanced enough to continue directly to Uppsala University. However, Wargentin's father wanted him first to attend the gymnasium (secondary school) of Härnösand, which he did. According to his own account, Wargentin was unimpressed with the purely classical and theological curriculum and the lack of any education in the sciences and did not finish the fourth year.

In 1735, Wargentin matriculated as a student at the University of Uppsala, where he excelled. Olof Hiorter was one of his instructors. He graduated in 1743 and became a docent in astronomy in 1746 and an adjunct in 1748. He was called to Stockholm as secretary of the Royal Swedish Academy of Sciences in 1749 on the death of secretary Pehr Elvius, Jr., and stayed on this post until his death. Wargentin therefore became the first long-serving secretary of the Academy, which had been founded in 1739. He is seen as an important person in leading the Academy to its first golden era. Wargentin also became the first director of the Stockholm Observatory founded by the Academy of Sciences on the initiative of his predecessor, Elvius, and completed in 1753.

Wargentin made studies on the moons of Jupiter and published his first paper on the topic in 1741 in the Acta of the Royal Society of Sciences in Uppsala.

The crater Wargentin on the Moon is named in his honor.

September 21: Arthur Covington

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Arthur Edwin Covington

September 21, 1913 – March 17, 2001

Arthur Covington is a Canadian physicist who made the first radio astronomy measurements in Canada. Through these he made the valuable discovery that sunspots generate large amounts of microwaves at the 10.7 cm wavelength, offering a simple all-weather method to measure and predict sunspot activity, and their associated effects on communications. The sunspot detection program has run continuously to this day.

Covington was born in Regina and grew up in Vancouver. He showed an early interest in astronomy, and had built a 5-inch (130 mm) refractor telescope after meeting members of the local chapter of the Royal Astronomical Society of Canada. He was also interested in amateur radio and operated station VE3CC for a time. He started his career as a radio operator on ships operated by the Canadian National Railways. He put himself though school and eventually earned a bachelor's degree from the University of British Columbia in 1938, and obtained his master's degree from the same institution in 1940 after building an electron microscope. He then moved to University of California in Berkeley where he received his doctoral degree in nuclear physics in 1942. He was still at Berkeley when he was invited to join the National Research Council (NRC) in Ottawa in 1942 as a radar technician, working at the NRC's Radio Field Station.

Immediately after the war Covington became interested in radio astronomy, and built a small telescope out of the electronic parts from a surplus SCR-268 radar combined with parts from another receiver originally built to test silicon crystal radio parts for radar applications. These electronics were attached to the 4 ft (1.2 m) parabolic dish from a Type III gun-laying radar. The system operated at a frequency of 2800 MHz, or a wavelength of 10.7 cm. Initially the instrument was pointed in the direction of various celestial objects, including Jupiter, the Milky Way, aurora borealis, and the Sun, but it proved too insensitive to pick up any source other than the Sun. So a solar study program was started. As time passed, Covington and his colleagues realized that the Sun's emission at 10.7 cm wavelength was varying, which was unexpected. Thinking at that time was that the solar emission at centimeter wavelengths would be simply black body emission from a ball of hot gas.

Covington became convinced that the effect was due to sunspots, as the flux appeared to vary with the number of visible spots. The resolution of the device, about seven degrees, made it impossible to "pick out" a spot on the sun's surface for study, making a demonstration of the claim difficult. An opportunity to directly measure this possibility presented itself on November 23, 1946 when a partial solar eclipse passed over the Ottawa area, and Covington was able to conclusively demonstrate that the microwave emissions dropped off precipitously when the Moon covered a particularly large sunspot. This also demonstrated that magnetic fields were instrumental in sunspot activity.

Covington remained the director of the ARO until he retired in 1978. One of the buildings at the Dominion Astrophysical Observatory was named in his honour in 2003.

September 20: Gherman Titov

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Gherman Stepanovich Titov

September 11, 1935 – September 20, 2000

Gherman Titov was a Soviet cosmonaut and the second man to orbit the Earth.

Titov went to school at the Stalingrad Military Aviation School. After graduating as an air force pilot, he was selected for cosmonaut training in 1960, and from there was chosen to fly the Vostok 2 mission launched in August 6, 1961. The mission lasted for 25.3 hours and accomplished 17 earth orbits. His call sign in this flight was Eagle. He landed close to the town of Krasny Kut in Saratov Oblast, Russia. A month short of 26 years old at launch, he remains the youngest person to fly in space.

His name refers to Saint Germanus and not to "a German".

In August 1961, he was the first person to suffer from "space sickness" (i.e. motion sickness in space) and was also the first human to sleep in space. He slept roughly for one orbit, and was surprised to awake with his arms floating in the air due to the absence of gravity. After securing his arms under a security belt, he went back to sleep, overslept and awoke 30 minutes later than predicted by the flight plan. He states (in the English version of his biography) that

"Once you have your arms and legs arranged properly, space sleep is fine ... I slept like a baby".

Following his space flight, Titov went on to assume various senior positions in the Soviet space programme until his retirement in 1992.

The crater Titov on the far side of the Moon is named in his honor.

September 19: Jean-Baptiste Delambre

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Jean Baptiste Joseph, chevalier Delambre

September 19, 1749 - August 19, 1822

Jean-Baptiste Delambre was a French mathematician and astronomer. He was also director of the Paris Observatory, and author of well-known books on the history of astronomy from ancient times to the 18th century.

After a childhood fever, he suffered from very sensitive eyes, and believed that he would soon go blind. For fear of losing his ability to read, he devoured any book available to him and practised his ability to memorise. He thus immersed himself in Greek and Latin literature, acquired the ability to recall verbatim entire pages of books he may have read weeks beforehand, became fluent in Italian, English and German and even published Règles et méthodes faciles pour apprendre la langue anglaise (Easy rules and methods for learning English). In 1788, he was elected a foreign member of the Royal Swedish Academy of Sciences.

In 1801, First Consul Napoléon Bonaparte took the presidency of the Academy of Sciences and appointed Delambre its Permanent Secretary for the Mathematical Sciences, a post he held until his death.

After Méchain's death in 1804, he was appointed director of the Paris Observatory. He was also professor of Astronomy at the Collège de France. The same year he married Elisabeth-Aglaée Leblanc de Pommard, a widow with whom he had lived already for a long time. Her son, Achille-César-Charles de Pommard (1781-1807) assisted Delambre on several occasions in his astronomical and geodetical surveys, notably the measuring of the baselines for the meridian survey, and the latitude definition for Paris in December 1799 which was presented to the Conference of Savants.

Delambre was one of the first astronomers to derive astronomical equations from analytical formulas, was the author of Delambre's Analogies and, after the age of 70, also the author of works on the history of astronomy like the Histoire de l'astronomie.

He was a knight (chevalier) of the Order of Saint Michael and of the Légion d'honneur.

The crater Delambre on the Moon is named in his honor.

September 18: John Cobb Cooper, Jr.

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John Cobb Cooper, Jr.

September 18, 1887 - July 22, 1967

John Cobb Cooper, Jr. was an American jurist, airline executive and presidential advisor.

From 1927–34 he was Editor-in-Chief of the Florida State Bar Association Law Journal. He was appointed to the International Technical Committee of Legal Aerial Experts, 1932–34. He became Vice President of Pan American Airways 1934–45, serving on the board of directors 1944–46. In 1947 he served as a consultant to the U.S. President's Air Policy Commission. He was a fellow at the Institute for Advanced Study in Princeton, 1945–50. In 1952 he was awarded his LL.D. from McGill University. From 1951–57 he was professor of International Air Law at McGill University, becoming the first director of the Institute of International Air Law, after which he was named Professor Emeritus.

He was the author of the book "The Right to Fly" and pioneered legal thought on air/space rights of man-made satellites in orbit, commencing with the launch of Sputnik in October 1957 when asked by President Eisenhower to render a legal opinion on "flyover rights" when Sputnik was orbiting over the United States. His honorary Doctorate from his alma mater, Princeton University, declared him the "Father of Air Space Law."

He was the legal counsel to the International Air Transport Association (IATA) from the early 1950s through the end of his life.

He was a pioneer in the field of international law as it applied to air and space. He wrote the first article on the topic of space ownership, "High Altitude Flight and National Sovereignty," in 1951.

His younger brother was movie producer Merian C. Cooper, perhaps most famous for the creation of the movie King Kong in 1933, and whose position as a Director of Pan Am was responsible for recommending his older brother for the position of Pan Am's legal consel and Vice President.

He flew with Charles Lindbergh, a consultant for PanAm, in small aircraft on site surveys to select sites in Ireland (Shannon) and France (Orly) for airports as Pan Am's services overseas increased.

The crater Cooper on the far side of the Moon is named in his honor.

September 17: Konstantin Tsiolkovsky

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Konstantin Eduardovich Tsiolkovsky

September 17, 1857 – September 19, 1935

Konstantin Tsiolkovsky was an Imperial Russian and Soviet rocket scientist and pioneer of the astronautic theory. He is considered by many to be the father of theoretical astronautics. His works later inspired leading Soviet rocket engineers such as Sergey Korolyov and Valentin Glushko and contributed to the early success of the Soviet space program.

Tsiolkovsky theorized many aspects of space travel and rocket propulsion. He is considered the father of spaceflight and the first man to conceive the space elevator, becoming inspired in 1895 by the newly-constructed Eiffel Tower in Paris.

He was also an adherent of philosopher Nikolai Fyodorov, and believed that colonizing space would lead to the perfection of the human race, with immortality and a carefree existence.

In the late 19th and early 20th century, Tsiolkovsky delved into theories of heavier-than-air flying machines, independently working through many of the same calculations that the Wright brothers were doing at the same time. However, he never built any practical models, and his interest shifted to more ambitious topics. Because Tsiolkovsky's ideas were little known outside Imperial Russia, the field lagged until German and other scientists independently made the same calculations decades later.

In 1923, German physicist Hermann Oberth published his thesis By Rocket into Planetary Space, which triggered wide-scale interest and scientific research on the topic of space flight. It also reminded Friedrich Zander about once having read an article on the subject. After contacting the author, he became active in promoting and further developing Tsiolkovsky's work. In 1924 Zander established the first astronautics society in the Soviet Union, the Society for Studies of Interplanetary Travel, and later researched and built liquid-fuelled rockets named OR-1 (1930) and OR-2 (1933).

In 1924, a writer for the Russian newspaper Izvestiia reported on A Method of Reaching Extreme Altitudes, a groundbreaking work on the rocketry experiments being done by Robert Goddard, which had been published in 1919 but was not noticed in the Soviet Union until Hermann Oberth referenced it in his later work. When news of the article reached Tsiolkovsky, he decided to republish his early works along with a flurry of new articles about space.

His most important work, published in 1903, was The Exploration of Cosmic Space by Means of Reaction Devices, arguably the first academic treatise on rocketry. Tsiolkovsky calculated that the horizontal speed required for a minimal orbit around the Earth is 8,000 m/s (5 miles per second) and that this could be achieved by means of a multistage rocket fueled by liquid oxygen and liquid hydrogen.

During his lifetime he published over 500 works on space travel and related subjects, including science fiction novels. Among his works are designs for rockets with steering thrusters, multi-stage boosters, space stations, airlocks for exiting a spaceship into the vacuum of space, and closed cycle biological systems to provide food and oxygen for space colonies.

Tsiolkovsky's work influenced later rocketeers throughout Europe, like Wernher von Braun, and was also studied by the Americans in the 1950s and 1960s as they sought to understand the Soviet Union's successes in space flight.

The crater Tsiolkovskiy (the most prominent crater on the far side of the Moon) was named after him. The Soviet Union obtained naming rights by operating Luna 3, the first space device to successfully transmit images of the side of the moon not seen from Earth.

September 16: Francesco Maurolico

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Francesco Maurolico

September 16, 1494 - July 21, 1575

Francesco Maurolico (in Latin, Franciscus Maurolycus) was an Italian mathematician and astronomer. Throughout his lifetime, he made contributions to the fields of geometry, optics, conics, mechanics, music, and astronomy.

Between 1548 and 1550, Maurolico stayed at the castle of Pollina in Sicily as a guest of the marquis Giovanni II Ventimiglia, and utilized the castle tower in order to carry out astronomical observations.

Maurolico's astronomical observations include a sighting of the supernova that appeared in Cassiopeia in 1572. Tycho Brahe published details of his observations in 1574; the supernova is now known as Tycho's Supernova.

In 1569, he was appointed professor at the University of Messina.

Maurolico's Photismi de lumine et umbra and Diaphana concern the refraction of light and attempted to explain the natural phenomenon of the rainbow. He also studied the camera obscura. His Arithmeticorum libri duo (1575) includes the first known proof by mathematical induction.

Maurolico published a Cosmographia in which he described a methodology for measuring the earth, which was later employed by Jean Picard in measuring the meridian in 1670.

Maurolico published an edition of Aristotle's Mechanics, and a work on music. He summarized Ortelius's Theatrum orbis terrarum and also wrote Grammatica rudimenta (1528) and De lineis horariis. He made a map of Sicily, which was published in 1575.

Maurolico worked on ancient mathematical texts: Theodosius of Bithynia, Menelaus of Alexandria, Autolycus of Pitane, Euclid, Apollonius of Perga and Archimedes. His didn't make new translations, but working on the existing ones, he provided new and sound interpretations of Greek mathematics.

The lunar crater Maurolycus is named after him.

September 15: Jean-Sylvain Bailly

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Jean-Sylvain Bailly

September 15, 1736 – November 12, 1793

Jean-Sylvain Bailly was a French astronomer and orator, one of the leaders of the early part of the French Revolution. He was ultimately guillotined during the Reign of Terror.

Born in Paris, he was originally intended for the profession of a painter, but preferred writing tragedies, until attracted to science by the influence of Nicolas de Lacaille. He calculated an orbit for Halley's Comet when it appeared in 1759, reduced Lacaille's observations of 515 zodiacal stars, and was elected a member of the French Academy of Sciences in 1763. His Essai sur la theorie des satellites de Jupiter (Essay on the theory of the satellites of Jupiter, 1766), an expansion of a memoir presented to the Academy in 1763, showed much original power; and it was followed up in 1771 by a noteworthy dissertation Sur les inegalites de la lumiere des satellites de Jupiter (On the inequalities of light of the satellites of Jupiter). In 1778, he was elected a foreign member of the Royal Swedish Academy of Sciences.

Meantime, he had gained a high literary reputation by his Éloges of King Charles V of France, Lacaille, Molière, Pierre Corneille and Gottfried Leibniz, which were issued in collected form in 1770 and 1790; he was admitted to the Académie française on 26 February 1784, and to the Académie des Inscriptions in 1785, when Bernard le Bovier de Fontenelle's simultaneous membership of all three Academies was renewed in him.

From then on, he devoted himself to the history of science, publishing successively: Histoire de l'astronomie ancienne (A history of ancient astronomy, 1775); Histoire de l'astronomie moderne (A history of modern astronomy, 3 vols., 1779-1782); Lettres sur l'origine des sciences (Letters on the origin of the sciences, 1777); Lettres sur l' Atlantide de Platon (Letters on Plato's Atlantide , 1779); and Traite de l'astronomie indienne et orientale (A treatise on Indian and Oriental astronomy, 1787). The 1911 Encyclopædia Britannica remarks that "Their erudition was… marred by speculative extravagances."

The lunar crater Bailly is named in his honor.

September 14: Johann Kies

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Johann Kies

September 14, 1713—July 29, 1781

Johann Kies was a German astronomer and mathematician. Born in Tübingen, Kies worked in Berlin in 1751 alongside Jérôme Lalande in order to make observations on the lunar parallax in concert with those of Nicolas Louis de Lacaille at the Cape of Good Hope.

From 1742 to 1754, at the recommendation of the mathematician Leonhard Euler, he was made professor of mathematics at Berlin's Academy of Sciences and astronomer at its observatory. His reports from this time include De la Situation la plus avantageuse des planètes pour découvrir les irrégularités de leurs mouvemens, Sur les Éclipses des étoiles fixes par la lune, and Description d'un instrument qui se trouve à l'observatoire de Berlin. In his Rapport de quelques observations célestes faites à l'observatoire Royal, Kies wrote, "

Observations on eclipses are extremely useful, especially the ones that are exact. They serve primarily to understand, if the theories on the Sun and the Moon are well or badly ascertained in the astronomical tables, and can either confirm them, or give us a need to reform them."

He subsequently taught also at the Collegium of Tübingen. From 1754 to 1755, Kies served as director of the Astronomisches Rechen-Institut in Heidelberg.

Kies was one of the first to propagate Newton's discoveries in Germany, and dedicated two of his works to the Englishman: De viribus centralibus (Tübingen, 1758) and De lege gravitatis (Tübingen, 1773). Kies is also the author of a work on lunar influences: De influxu lunae in partes terrae mobiles (Tübingen, 1769). He wrote many other works, both in French and in Latin, on astronomy.

Kies corresponded with Euler from 1747 to 1767. Their correspondence consists of 8 letters, all of which were written by Kies.

The crater Kies on the Moon is named in his honor.

September 13: Horace W. Babcock

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Horace Welcome Babcock

September 13, 1912 – August 29, 2003

Horace Babcock was an American astronomer. He was the son of Harold D. Babcock.

He invented and built a number of astronomical instruments, and in 1953 was the first to propose the idea of adaptive optics. He specialized in spectroscopy and the study of magnetic fields of stars. He proposed the Babcock Model, a theory for the magnetism of sunspots.

During World War II, he was engaged in radiation work at MIT and Caltech. After the war he began a productive collaboration with his father.

Babcock was awarded the Henry Draper Medal (1957), the Eddington Medal (1958), the Bruce Medal (1969), the Gold Medal of the Royal Astronomical Society (1970) and the George Ellery Hale Prize of the American Astronomical Society Solar Physics Division (1992)

The asteroid 3167 Babcock is named jointly for Horace and his father. The Babcock crater on the Moon is named only for his father.

September 12: Guillaume Le Gentil

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The ruins of Pondicherry in 1769 seen from the north. Le Gentil’s observatory was in the structure to the right of the flag pole.

Guillaume Joseph Hyacinthe Jean-Baptiste Le Gentil de la Galaisière

September 12, 1725 – October 22, 1792

Guillaume Le Gentil was a French astronomer.

He was born in Coutances and first intended to enter the church before turning to astronomy. He discovered what are now known as the Messier objects M32, M36 and M38, as well as the nebulosity in M8, and he was the first to catalogue the dark nebula sometimes known as Le Gentil 3 (in the constellation Cygnus).

He was part of the international collaborative project to measure the distance to the Sun, by observing the transit of Venus at different points on the earth. Edmond Halley had suggested the idea, but it required careful measurements from different places on earth, and the project was launched with more than a hundred observers dispatched to different parts of the globe, for observing the transit coming up in 1761. The French expedition turned out to be particularly unlucky, and perhaps the most unfortunate was Guillaume le Gentil, who set out for Pondicherry, a French colony in India.

He set out from Paris in March 1760, and reached Île de France (Mauritius) in July. But having learned that war had broken out between France and Britain, and deeming it dangerous to try and reach Pondicherry, he determined to go elsewhere; a frigate was bound for India's Coromandel Coast, and he sailed in March 1761. When they had nearly arrived they learned that the British had occupied Pondicherry, so the frigate was obliged to return to Île de France. June 6, the day of the transit, came, and the sky was clear, but he could not take astronomical observations with the vessel rolling about. After having come this far, he thought he might as well await the next transit of Venus, which would come in another eight years (they are relatively infrequent, occurring in pairs 8 years apart, but each such pair is separated from the previous and next pairs by more than a century.)

After spending some time mapping the eastern coast of Madagascar, he decided to record the 1769 transit from Manila in the Philippines. Encountering hostility from the Spanish authorities there, he headed back to Pondicherry, which had been restored to France by peace treaty in 1763, where he arrived in March 1768. He built a small observatory and waited patiently. At last, the day in question (June 4, 1769) arrived, but although the mornings in the preceding month had all been lovely, on this day the sky became overcast, and Le Gentil saw nothing. The misfortune drove him to the brink of insanity, but at last he recovered enough strength to return to France.

The return trip was first delayed by dysentery, and further when his ship was caught in a storm and dropped him off at Île Bourbon (Réunion), where he had to wait until a Spanish ship took him home. He finally arrived in Paris eleven years later in October 1771, only to find that he had been declared legally dead and been replaced in the Royal Academy of Sciences. His wife had remarried, and all his relatives had "enthusiastically plundered his estate". Lengthy litigation and the intervention of the king were ultimately required before things were normalized. He got back his seat in the academy, remarried, and lived apparently happily for another 21 years.

One of his interesting findings was that the duration of the lunar eclipse of 30 August 1765 was predicted by a Tamil astronomer, based on the computation of the size and extent of the earth-shadow (going back to Aryabhata, 5th c.), and was found short by 41 seconds, whereas the charts of Tobias Mayer were long by 68 seconds.

The Lunar crater Le Gentil is named in his honor.

September 11: Mary Watson Whitney

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Mary Watson Whitney

September 11, 1847 – January 20, 1921

Mary Watson Whitney was an American astronomer and for 22 years the head of the Vassar Observatory.

Whitney was born in Waltham, Massachusetts in 1847. She went to school in Waltham and graduated from the public high school in 1863. Afterwards she entered Vassar College, where she met the astronomer Maria Mitchell.

She got her degree in 1868 and returned to Waltham to care for her widowed mother. At that time she worked as a teacher in Auburndale, Massachusetts.

Starting in 1869 she had some courses about quaternions (at Harvard) and celestial mechanics by Benjamin Peirce. She got her masters degree from Vassar in 1872, afterwards she went to Zürich for 3 years. Returning to the U.S. she became a teacher at her hometown high school until she became an assistant of Maria Mitchell in Vassar.

In 1888 she fellowed Mitchell as professor and as director of the observatory there until she retired in 1910 for health reasons. She died in Waltham in 1921.

September 10: James Edward Keeler

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James Edward Keeler

September 10, 1857 – August 12, 1900

James Edward Keeler was an American astronomer.

Keeler worked at Lick Observatory beginning in 1888, but left after being appointed director of the University of Pittsburgh's Allegheny Observatory in 1891. He returned to Lick Observatory as its director in 1898, but died not long after in 1900. His ashes were interred in a crypt at the base of the 31-inch Keeler Memorial telescope at the Allegheny Observatory.

Along with George Hale, Keeler founded and edited the Astrophysical Journal, which remains a major journal of astronomy today.

Keeler was the first to observe the gap in Saturn's rings now known as the Encke Gap, using the 36-inch refractor at Lick Observatory on 7 January 1888. After this feature had been named for Johann Encke, who had observed a much broader variation in the brightness of the A Ring, Keeler's contributions were brought to light. The second major gap in the A Ring, discovered by Voyager, was named the Keeler Gap in his honor.

In 1895, his spectroscopic study of the rings of Saturn revealed that different parts of the rings reflect light with different Doppler shifts, due to their different rates of orbit around Saturn. This was the first observational confirmation of the theory of James Clerk Maxwell that the rings are made up of countless small objects, each orbiting Saturn at its own rate. These observations were made with a spectrograph attached to the 13-inch Fitz-Clark refracting telescope at Allegheny Observatory.

His observations with the Lick Crossley telescope helped establish the importance of large optical reflecting telescopes, and expanded astronomers' understanding of nebulae. After his untimely death, his colleagues at Lick Observatory arranged for the publication of his photographs of nebulae and clusters in a special volume of the Lick Observatory publications. Keeler discovered two asteroids, one in 1899 and one in 1900, although the second was lost and only recovered about 100 years later.

He won the Henry Draper Medal in 1899.

In 1880, Allegheny Observatory director Samuel Pierpont Langley, accompanied by Keeler and others, went on a scientific expedition to the summit of Mount Whitney. The purpose of the expedition was to study how the Sun's radiation was selectively absorbed by the Earth's atmosphere, comparing the results at high altitude with those found at lower levels. As a result of the expedition, a 14,240-ft. peak near Mount Whitney was named the "Keeler Needle".

In addition to the Keeler Gap in Saturn's rings, craters on Mars and the Moon (Keeler) are named in his honor, as is the asteroid 2261 Keeler.

September 9: William Cranch Bond

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William Cranch Bond

September 9, 1789 – January 29, 1859

William Cranch Bond was an American astronomer, and the first director of Harvard College Observatory.

William Cranch Bond was born in Falmouth, Maine (now Portland, Maine). When he was young, his father, William Bond, established himself as a clockmaker after a failed business venture; trained by his father and aided by his penchant for engineering, W. C. Bond built his first clock when he was fifteen years old. He eventually took over his father’s business, becoming an expert clockmaker himself.

In 1806, when he was seventeen years old, Bond saw a solar eclipse. Soon thereafter, he became an avid amateur astronomer. When he built his first house, Bond made its parlor an observatory, complete with an opening in the ceiling out of which his telescope could view the sky.

In 1815, Bond traveled to Europe, commissioned by Harvard University to gather information on European observatories. On 18 July 1819 at Kingsbridge in Devon, Bond married his first cousin, Selina Cranch, who bore him four sons and two daughters. After Selina's death in 1831, Bond married her older sister, Mary Roope Cranch.

In 1839, Bond was allowed to move his personal astronomical equipment to Harvard and serve as its (unpaid) "Astronomical Observer to the University." Later, in 1843, a sun-grazing comet aroused enough public interest in astronomy that Harvard was able to raise $25,730 towards the construction of a state-of-the-art observatory. Bond designed the building and the observing chair (both of which are still in working order today), and Harvard bought a fifteen-inch German-built refracting telescope, equal in size to the largest in the world at the time. The telescope was first put to use on June 24, 1847, when it was pointed to the moon.

Bond and his son George Phillips Bond discovered Saturn's moon Hyperion; it was independently co-discovered at the same time by William Lassell in Britain, and both are given credit. He also independently discovered the Great Comet of 1811.

Father and son were the first to observe the then innermost ring of Saturn, termed the Crepe ring when they pointed Harvard’s telescope towards Saturn in 1850.

Working with John Adams Whipple, the Bonds pioneered astrophotography, taking the first daguerreotype image of a star (Vega, in 1850) ever taken from America. In all, the threesome took between 200 and 300 photos of celestial objects.

A number of celestial objects have been named in Bond's honor. A few of them include:

The crater W. Bond on the Moon.
A region on Hyperion is called the "Bond-Lassell Dorsum".
Asteroid (767) Bondia is jointly named after him and his son.
The Bond Gap within Saturn's C Ring is jointly named after him and his son.

September 8: Johannes Wilsing

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Johannes Wilsing

September 8, 1856 – December 23, 1943

Johannes Wilsing was a German astronomer.

He was born in Berlin, where he was educated in addition to Göttingen. In 1880 he was awarded his Ph.D. from Humboldt-Universität of Berlin with a dissertation titled, Über den Einfluss von Luftdruck und Wärme auf die Pendelbewegung (On the influence of air pressure and heat on the movement of a pendulum).

In 1881 he joined the Astrophysical Observatory Potsdam (AOP) as an assistant, and would remain there until he retired. His early career was spent on solar studies, including observations of sunspots and derivations of the rotation period. In 1897 he measured the parallax of 61 Cygni, a relatively nearby star.

He became an observer at the AOP in 1898, and the following year he collaborated with Julius Scheiner in an unsuccessful attempt to measure the radio emission from the Sun. The same year he attempted to interpret the spectrum of novae. He performed extensive work on the luminosity, colors, and diameters of stars.

The Lunar crater Wilsing is named in his honor.

September 7: James Van Allen

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James Alfred Van Allen

September 7, 1914 – August 9, 2006

James Van Allen was an American space scientist at the University of Iowa. The Van Allen radiation belts were named after him, following the 1958 satellite missions (Explorer 1 and Explorer 3) in which Van Allen had argued that a Geiger counter should be used to detect charged particles.

Van Allen received his Bachelor of Science degree, summa cum laude, from Iowa Wesleyan College in 1935. During his undergraduate years, he studied with Professor Thomas Poulter, a first-class physicist. He tracked meteors, conducted a magnetic survey of Mount Pleasant, and measured cosmic rays at ground level. He earned his master’s degree in solid state physics and his Ph.D. in nuclear physics from the University of Iowa. His doctoral research was on measuring the cross-section of the deuteron-deuteron reaction.

As a staff physicist for the Department of Terrestrial Magnetism of the Carnegie Institution in Washington, D.C., Van Allen worked on developing photoelectric and radio proximity fuzes for bombs, rockets, and gun-fired projectiles. It was here that Dr. Van Allen acquired his interest in cosmic rays.

In 1950 an event occurred that began small but was to affect the future of Van Allen and all his countrymen. In March, British Physicist Sydney Chapman dropped in on Van Allen [and] remarked that he would like to meet other scientists in the Washington area. Van Allen got on the phone, soon gathered eight or ten top scientists (Lloyd Berkner, S. Fred Singer, and Harry Vestine) in the living room of his small brick house. ‘It was what you might call a pedigreed bull session,’ he says. ... The talk turned to geophysics and the two ‘International Polar Years’ that had enlisted the world’s leading nations to study the Arctic and Antarctic regions in 1882 and 1932. Someone suggested that with the development of new tools such as rockets, radar and computers, the time was ripe for a worldwide geophysical year. The other men were enthusiastic, and their enthusiasm spread around the world from Washington DC. From this meeting Lloyd Berkner and other participants proposed to the International Council of Scientific Unions that an IGY be planned for 1957-58 during the maximum solar activity). ... The International Geophysical Year (1957-58) stimulated the U.S. Government to promise earth satellites as geophysical tools. The Soviet government countered by rushing its Sputniks into orbit. The race into space or Space Race may be said to have started in Van Allen’s living room that evening in 1950.
– TIME, 1959

On October 4, 1957 the Soviet Union (USSR) successfully launched Sputnik 1, the world's first artificial satellite, as part of their participation in the IGY.

The first American satellite, Explorer 1, was launched into Earth's orbit on January 31, 1958 on a Jupiter C missile from Cape Canaveral, Florida. Aboard Explorer 1 were a micrometeorite detector and a cosmic ray experiment designed by Dr. Van Allen and his graduate students. Data from Explorer 1 and Explorer 3 (launched March 26, 1958) were used by the Iowa group to make the first space-age scientific discovery: the existence of a doughnut-shaped region of charged particle radiation trapped by Earth’s magnetic field.

Pioneer 3, the third intended U.S. International Geophysical Year lunar probe under the direction of NASA with the Army acting as executive agent, was launched from the Atlantic Missile Range by a Juno II rocket. The primary objective of the flight, to place the 12.95 pound (5.87 kg) scientific payload in the vicinity of the moon, failed. Pioneer III did reach an altitude of 63,000 miles (101 Mm), providing Van Allen additional data that led to discovery of a second radiation belt. Trapped radiation starts at an altitude of several hundred miles from Earth and extends for several thousand miles into space. The Van Allen radiation belts are named for Dr. James Van Allen, their discoverer.

In 1959 TIME magazine credited James Van Allen as the man most responsible for giving the U.S. “a big lead in scientific achievement.” They called Van Allen “a key figure in the cold war’s competition for prestige. ...Today he can tip back his head and look at the sky. Beyond its outermost blue are the world-encompassing belts of fierce radiation that bear his name. No human name has ever been given to a more majestic feature of the planet Earth.”

September 6: Yrjö Väisälä

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Yrjö Väisälä

September 6, 1891 – July 21, 1971

Yrjö Väisälä was a Finnish astronomer and physicist.

His main contributions were in the field of optics, but he was also very active in geodetics, astronomy and optical metrology. He even had an affectionate nickname of Wizard of Tuorla (Observatory/Optics laboratory), and there is a book with the same title in Finnish describing his works.

He developed several methods for measuring the quality of optical elements, as well as a lot of practical methods of manufacturing said elements. This allowed the construction of some of the earliest high-quality Schmidt cameras, in particular a "field-flattened" version known as Schmidt-Väisälä camera.

Contemporary to Bernhard Schmidt's design, but unpublished was also Prof. Yrjö Väisälä's identical design which he had mentioned in lecture notes in 1924 with a footnote: "problematic spherical focal surface".

Once he saw Schmidt's publication, he promptly went ahead and "solved" the field flattening problem by placing a doubly-convex lens slightly in front of the film holder (back in the 1930s, astronomical films were glass plates.) The resulting system is known as the Schmidt-Väisälä camera or sometimes as the Väisälä camera. (This solution is not perfect, as images of different colour end up at slightly different places.)

Prof. Väisälä made a small test unit of 7 mirrors in a mosaic on stiff background steel frame, however it proved to be impossible to stabilize as "just adjust and forget" structure, and next time anybody tried it, was with active controls on the Multiple Mirror Telescope.

The big Schmidt-Väisälä telescope he built was used at the University of Turku for searching asteroids and comets. His research group discovered 7 comets and 807 asteroids.

For this rather massive photographic survey work, Prof. Väisälä developed also a protocol of taking two exposures on same plate some 2–3 hours apart and offsetting those images slightly. Any dot-pairs that differed from background were moving, and deserved follow-up photos. This method halved the film consumption compared to method of "blink comparing", where plates get single exposures, and are compared by rapidly showing first and second exposures to human operator. (Blink-comparing was used to find e.g. Pluto.)

The University of Turku Astronomy department is known as VISPA: Väisälä Institute for Space Physics and Astronomy in honour of its founder.

The Lunar crater Väisälä and the asteroid 1573 Väisälä are also named in his honor.

Yrjö Väisälä discovered 128 asteroids. He used to name them with the names of his personal friends that had birthdays. One of them was the professor Matti Palomaa, after whom an asteroid 1548 Palomaa was named. (For this reason the Palomar Mountain Observatory in California has never had an asteroid bearing its name – the rules for naming asteroids state that the names have to differ from each other with more than one letter.)

September 5: Andriyan Nikolayev

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Andriyan Grigoryevich Nikolayev

September 5, 1929 – July 3, 2004

Andriyan Nikolayev was a Soviet cosmonaut.

Nikolayev flew on two space flights: Vostok 3 (effectively becoming the third Soviet cosmonaut) and Soyuz 9. His call sign in these flights was Falcon. On both, he set new endurance records for the longest time a human being had remained in orbit. He also served as backup for the Vostok 2 and Soyuz 8 missions. He left the cosmonaut corps on January 26, 1982.

Nikolayev was also the first person to make a television broadcast from space, in August 1962. Vostok 3 was part the first dual space flight, with Pavel Popovich on Vostok 4.

In the early days of space travel, it was usual to place trainee astronauts into isolation chambers to see how long they could last alone. They sat in silence unable to gauge time. Many men cracked. One cosmonaut, Andriyan Nikolayev lasted the longest - four days - and became known as the Iron Man.

On November 3, 1963, he married Valentina Tereshkova, the first woman to fly in space (see Vostok 6). They had one daughter, Elena Andriyanovna (now a Doctor of Medicine).

Andriyan Nikolayev was awarded the title of Hero of the Soviet Union (twice), Order of Lenin, Order of the Red Star, numerous medals, and foreign orders. He was also bestowed a title of the Hero of Socialist Labor of Bulgaria, Hero of Labor of Vietnam, and Hero of Mongolia. The lunar crater Nikolayev is named in his honor.

September 4: Max Delbrück

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Max Ludwig Henning Delbrück

September 4, 1906 – March 9, 1981

Max Delbrück was a German-American biophysicist and Nobel laureate.

Delbrück was born in Berlin, German Empire. His father was Hans Delbrück, a professor of history at the University of Berlin, and his mother was the granddaughter of Justus von Liebig.

Delbrück studied astrophysics, shifting towards theoretical physics, at the University of Göttingen. After receiving his Ph.D. in 1930, he traveled through England, Denmark, and Switzerland. He met Wolfgang Pauli and Niels Bohr, who got him interested in biology.

Delbrück went back to Berlin in 1932 as an assistant to Lise Meitner, who was collaborating with Otto Hahn on the results of irradiating uranium with neutrons. During this period he wrote a few papers, one of which turned out to be an important contribution on the scattering of gamma rays by a Coulomb field due to polarization of the vacuum produced by that field (1933). His conclusion proved to be theoretically sound but inapplicable to the case in point, but 20 years later Hans Bethe confirmed the phenomenon and named it "Delbrück scattering".

In 1937, he moved to the United States to pursue his interests in biology, taking up research in the Biology Division at Caltech on genetics of the fruit fly Drosophila melanogaster.

Delbrück was one of the most influential people in the movement of physical scientists into biology during the 20th century. Delbrück's thinking about the physical basis of life stimulated Erwin Schrödinger to write the highly influential book, What Is Life?. Schrödinger's book was an important influence on Francis Crick, James D. Watson and Maurice Wilkins who won a Nobel prize for the discovery of the DNA double helix.

September 3: Heinrich Schumacher

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Heinrich Christian Schumacher

September 3, 1780 – December 28, 1850

Heinrich Schumacher was a German astronomer. He was director of the Mannheim observatory from 1813 to 1815, and then became professor of astronomy in Copenhagen. From 1817 he directed the triangulation of Holstein, to which a few years later was added a complete geodetic survey of Denmark (finished after his death). For the sake of the survey an observatory was established at Altona, and Schumacher resided there permanently, chiefly occupied with the publication of Ephemerides (11 parts, 1822–1832) and of the journal Astronomische Nachrichten (founded by himself in 1821 and still being published), of which he edited thirty-one volumes.

In 1827 he was elected member of the Royal Swedish Academy of Sciences, and in 1829 he won the Gold Medal of the Royal Astronomical Society.

His son, Richard Schumacher (1827-1902), was his assistant from 1844 to 1850 at the conservatory at Altona. Having become assistant to Carlos Guillermo Moesta (1825-1884), director of the observatory at Santiago de Chile, in 1859, he was associated with the Chilean geodesic survey in 1864. Returning in 1869, he was appointed assistant astronomer at Altona in 1873, and afterwards at Kiel.

Schumacher's nephew, Christian Andreas Schumacher (1810-1854), was associated with the geodetic survey of Denmark from 1833 to 1838, and afterwards (1844-1845) improved the observatory at Pulkowa.

The Lunar crater Schumacher is named in his honor.

September 2: Christa McAuliffe

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Sharon Christa Corrigan McAuliffe

September 2, 1948 – January 28, 1986

Sharon Christa Corrigan McAuliffe née Sharon Christa Corrigan, was an American teacher from Concord, New Hampshire. McAuliffe was born in Boston, Massachusetts, and received her bachelor's degree in education and history from Framingham State College in 1970, and a Master of Arts from Bowie State University in 1978. She took a teaching post as a social studies teacher at Concord High School in New Hampshire in 1982.

In 1985, McAuliffe was selected from more than 11,000 applicants to participate in the NASA Teacher in Space Project, and she was scheduled to become the first teacher in space. As a member of mission STS-51-L, she was planning to conduct experiments and teach two lessons from Space Shuttle Challenger. On January 28, 1986, her spacecraft disintegrated 73 seconds after launch, and she was one of seven crew members killed in the Space Shuttle Challenger disaster. After her death, schools and scholarships were named in her honor, and in 2004 she was awarded the Congressional Space Medal of Honor.

I cannot join the space program and restart my life as an astronaut, but this opportunity to connect my abilities as an educator with my interests in history and space is a unique opportunity to fulfill my early fantasies.
—Christa McAuliffe, 1985

McAuliffe's remains were buried at Blossom Hill Cemetery in Concord, NH. She has since been honored at many events, including the Daytona 500 auto race in 1986. The Christa McAuliffe Planetarium/McAuliffe-Shepard Discovery Center in Concord and the Christa Corrigan McAuliffe Center for Education and Teaching Excellence at Framingham State College are named in her memory, as are the asteroid 3352 McAuliffe, the crater McAuliffe on the Moon, and a crater on the planet Venus, which was named McAuliffe by the Soviet Union. Approximately 40 schools around the world have been named after her, including the Christa McAuliffe Space Education Center in Pleasant Grove, Utah.

September 1: Dirk Brouwer

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Dirk Brouwer

September 1, 1902 – January 31, 1966

Dirk Brouwer was a Dutch-American astronomer.

He received his Ph.D. in 1927 at Leiden University in the Netherlands and then went to Yale University. From 1941 until 1966 he was editor of the Astronomical Journal.

He specialized in celestial mechanics and together with Gerald Clemence wrote the textbook Methods of Celestial Mechanics.

Dirk Brouwer was renowned for developing general methods for determining orbits and applying these methods to comets, asteroids, and planets. In 1951, he became one of the first to use electronic computers for astronomical computations. With this innovation, he calculated the orbits of the first artificial satellites, and from them, obtained increased knowledge of the shape of the earth, and re-determined astronomical constants. Brouwer's 1961 masterpiece, Methods of Celestial Mechanics, taught a generation of scientists.

Brouwer was awarded the Gold Medal of the Royal Astronomical Society (1955) and the Bruce Medal (1966).

The asteroid 1746 Brouwer, the crater Brouwer on the Moon (jointly with mathematician Luitzen Egbertus Jan Brouwer), the Dirk Brouwer Award of the Division on Dynamical Astronomy of the American Astronomical Society and the Dirk Brouwer Award of the American Astronautical Society are named in his honor.

August 31: George Sarton

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George Alfred Leon Sarton

August 31, 1884 - March 22, 1956

George Sarton is considered by some to be the "father" of the history of science, having established the history of science as a discipline in its own right. His Introduction to the History of Science is a mammoth three-volume, 4,236-page work which reviews and catalogs the scientific and cultural contributions of every civilization from antiquity through the fourteenth century. He was the author of 15 other books and over 300 articles on this subject.

Sarton was born in Ghent on August 31, 1884: he graduated from the university in 1906 and two years later won a gold medal for one of his papers on chemistry. He received his PhD in mathematics at the University of Ghent in 1911. He married Mabel Eleanor Elwes, an English artist, in 1911 and their daughter Eleanore Marie (usually: May) was born the following year. Though he emigrated to England after World War I broke out, he came to the United States in 1915, where he would live for the rest of his life. He worked for the Carnegie Foundation for International Peace and lectured at Harvard, 1916-18. He became a lecturer at Harvard University in 1920 and a professor of the history of science from 1940-1951. He was also a research associate of the Carnegie Institution of Washington, 1919-1948.

Sarton intended to complete an exhaustive nine volume history of science — which, during the preparation of the second volume, induced him to learn Arabic and travel around the Middle East inspecting original manuscripts of Islamic scientists — but at the time of his death only the first three volumes had been completed. (I. From Homer to Omar Khayyam. — II. From Rabbi Ben Ezra to Roger Bacon, pt. 1-2. — III. Science and learning in the fourteenth -century, pt. 1-2. 1927-48.) The project was inspired by his study of Leonardo da Vinci but the period of Leonardo's life was not reached before the death of Sarton.

After his death a representative selection of his papers was edited by Dorothy Stimson and published by Harvard University Press in 1962.

In honor of Sarton's achievements, the History of Science Society created the award known as the George Sarton Medal. It is the most prestigious award of the History of Science Society. It has been awarded annually since 1955 to an outstanding historian of science selected from the international scholarly community. The medal honors a scholar for lifetime scholarly achievement. Sarton was the founder of this society and of the serial publications Isis and Osiris which it publishes.

The Lunar crater Sarton is named in his honor.

August 30: Johann Hieronymus Schröter

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Johann Hieronymus Schröter

August 30, 1745 – August 29, 1816

Johann Hieronymus Schröter was a German astronomer. Schröter was born in Erfurt, and studied law at Göttingen University from 1762 until 1767, after which he started a ten-year-long legal practice.

In 1777 he was appointed Secretary of the Royal Chamber of George III in Hanover, where he made the acquaintance of two of William Herschel's brothers. In 1779 he acquired a three-foot-long (91 cm, almost one metre) achromatic refractor with 2.25-inch (57 mm) lens (50 mm) to observe the Sun, Moon and Venus. Herschel's discovery of Uranus in 1781 inspired Schröter to pursue astronomy more seriously, and he resigned his post and became chief magistrate and district governor of Lilienthal.

He made extensive drawings of the features of Mars, yet curiously he was always erroneously convinced that what he was seeing was mere cloud formations rather than geographical features. In 1791 he published an important early study on the topography of the Moon entitled Selenotopographische Fragmente zur genauern Kenntniss der Mondfläche. In 1793 he was the first to notice the phase anomaly of Venus, now known as the Schröter effect, where the phase appears more concave than geometry predicts.

In 1813, he suffered the disruptions of the Napoleonic Wars: his work was ruined by the French under Vandamme, who destroyed his books, writings and observatory. He never recovered from the catastrophe.

His drawings of Mars were not rediscovered until 1873 (by François J. Terby) and were not published until 1881 (by H. G. van de Sande Bakhuyzen), well after his death.

He was elected a member of the Royal Swedish Academy of Sciences in 1794.

The lunar crater Schröter, Vallis Schröteri (Schröter's Valley) and the Martian crater Schroeter are named in his honor.

August 28: George Alcock

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George Eric Deacon Alcock

August 28, 1912 – December 15, 2000

George Alcock was an English astronomer. He was one of the most successful visual discoverers of novae and comets.

Initially, his interest in astronomy involved observation of meteors and meteor showers, but in 1953 he decided to start searching for comets and in 1955 began searching for novae. His technique was to memorize the patterns of thousands of stars, so that he would visually recognize any intruder.

In 1959 he discovered comet C/1959 Q1 (Alcock), the first comet discovered in Britain since 1894, and only five days later discovered another, C/1959 Q2 (Alcock). He discovered two more comets in 1963 and 1965. He later discovered his first nova, Nova Delphini 1967 (HR Delphini), which turned out to have an unusual light curve. He discovered two more novas, LV Vul (in 1968) and V368 Sct (in 1970). He found his fifth and final comet in 1983: C/1983 H1 (IRAS-Araki-Alcock). In 1991 he found the nova V838 Her.

He was awarded an MBE, and the asteroid 3174 Alcock is named after him. He also maintained an active interest in meteorology (the study of weather, unrelated to his interest in meteors).

His achievements were fairly remarkable, and with the modern invention of CCDs and photometry and automated and computerized search programs that make his visual discovery techniques seem entirely quaint and obsolete, it is unlikely that such achievements will ever be repeated.

George Alcock was also a very good (probably under-respected) teacher of the 4th year at Southfields Junior School in Stanground, Peterborough.

We never really knew how well known or respected he was in astronomical circles. He sparked my interest in astronomy, showed us how to view sunspots on a wall or sheet of paper using binoculars, he also used to take small groups of us birdwatching in the fens in his own time. He called me "Spider Young" - said my handwriting looked as though a spider had fallen in a pot of ink and crawled over the page. - Philip Young (Southfields 1972)

Alcock won the Jackson-Gwilt Medal of the Royal Astronomical Society in 1963 and Amateur Achievement Award of the Astronomical Society of the Pacific in 1981. After his death, a plaque was placed in Peterborough Cathedral in his memory.