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WonderAstronomy biography

American astronomer Annie Jump Cannon sorted about 350,000 stars at Harvard by the pattern of dark lines in their light. Her classes, O, B, A, F, G, K and M, running from the hottest stars to the coolest, are still the standard way to group stars.

Annie Jump Cannon

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Cannon was one of the “Harvard computers”, a team of women hired to study photographs of the night sky on glass plates, often for about 25 cents an hour. When starlight is spread into a spectrum, a band of colours, dark lines appear that are left by the elements in the star. Earlier schemes used many letters; Cannon reordered and simplified them into one clear sequence, and in 1925 Cecilia Payne used her data in work showing that the sequence follows temperature. Nearly deaf after an illness, Cannon worked at legendary speed, classifying up to three stars a minute, and her results filled the Henry Draper Catalogue, published between 1918 and 1924. In 1925 she became the first woman to receive an honorary doctorate of science from Oxford University.

Türkçe oku
Amerikalı gökbilimci Annie Jump Cannon, Harvard'da yaklaşık 350.000 yıldızı ışıklarındaki karanlık çizgilerin düzenine göre sınıflandırdı. En sıcaktan en soğuğa uzanan O, B, A, F, G, K, M sınıfları bugün de yıldızları gruplamanın standart yoludur.

Cannon, “Harvard hesapçıları” diye anılan kadın ekibindendi. Bu kadınlar gökyüzünün cam plakalara çekilmiş fotoğraflarını inceliyor, çoğu zaman saatte yaklaşık 25 sent kazanıyordu. Yıldız ışığı bir renk şeridine, yani tayfa açıldığında, yıldızdaki elementlerin bıraktığı karanlık çizgiler görünür. Daha önceki sistemlerde çok sayıda harf kullanılıyordu; Cannon bunları yeniden sıralayıp sadeleştirerek tek ve açık bir diziye dönüştürdü. 1925'te Cecilia Payne onun verilerinden yararlanarak bu dizinin sıcaklığa göre ilerlediğini gösterdi. Geçirdiği bir hastalıktan sonra neredeyse hiç duyamayan Cannon efsanevi bir hızla çalışır, dakikada üç yıldıza kadar sınıflandırırdı. Sonuçları 1918–1924 arasında yayımlanan Henry Draper Kataloğu'nu doldurdu. 1925'te Oxford Üniversitesi'nden fahri bilim doktorası alan ilk kadın oldu.

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