December 19: Albert Michelson

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.

July 19: Edward Charles Pickering

Edward Charles Pickering

July 19, 1846–February 3, 1919

Edward Charles Pickering was an American astronomer and physicist, brother of William Henry Pickering.

Along with Carl Vogel, Pickering discovered the first spectroscopic binary stars. He wrote Elements of Physical Manipulations (2 vol., 1873–76).

Pickering attended Boston Latin School, and received his B.S. from Harvard in 1865. Later, he served as director of Harvard College Observatory from 1877 to his death in 1919, where he made great leaps forward in the gathering of stellar spectra through the use of photography. At Harvard, he recruited many women to work for him, including Annie Jump Cannon, Henrietta Swan Leavitt, and Antonia Maury. These women, who came to be known as "Pickering's Harem" by the scientific community, made several important discoveries at HCO.

In 1876 he co-founded the Appalachian Mountain Club.

In 1911 he co-founded the American Association of Variable Star Observers (AAVSO) with William T. Olcott.

Pickering received the Gold Medal of the Royal Astronomical Society (1886 and 1901), the Henry Draper Medal (1888) and the Bruce Medal (1908)

The Lunar crater Pickering, the crater Pickering Mars and the asteroid 784 Pickeringia are named in his honor.