April 14: Annie Russell Maunder

The original butterfly diagram drawn by Walter Maunder and Annie S. D. Maunder in 1904

 has been on display for some time at the High Altitude Observatory in Colorado.

Annie Scott Dill Maunder, née Russell

April 14, 1868 – September 15, 1947

Annie Maunder was a British astronomer and mathematician.

Annie received her secondary education at the Ladies Collegiate School in Belfast. Winning a prize in an 1886 internediate school examination, she was able to sit the Girton open entrance scholarship examination, and was awarded a three year scholarship. She studied at Cambridge University (Girton College) and in 1889 she passed the degree examinations with honors, as the top mathematician of her year at Girton, and ranked Senior Optime in the university class list. However the restrictions of the period did not allow her to receive the B.A. she had otherwise earned.

In 1891 she began work at the Greenwich Royal Observatory, serving as one of the "lady computers" assigned to the solar department. There she assisted E. Walter Maunder, and she spent much time photographing the Sun and tracking the movements of sunspots. (The solar maximum was in 1894.) The two were married in 1895, his second marriage, and Annie was required to resign from her job. However the two continued to collaborate, with Annie accompanied Walter on solar eclipse expeditions.

She published "The Heavens and their Story" in 1910, with he husband as the co-author. (She was credited by her husband as the primary author.) In 1916 she became the first woman elected to the Royal Astronomical Society. The investigations of the couple demonstrated a correlation between the variation in sunspot numbers and the climate of the Earth, leading to the discovery that the decrease period of solar activity during the Maunder Minimum likely resulted in the "little ice age".

Walter and Annie did not have any children, although he had five children from his previous marriage. Walter died in 1928, and she died in London, England in 1947.

The Lunar crater Maunder was co-named for Walter and Annie Maunder.