Why 2nd Brightest Castor is alpha Geminorum

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mikemarotta
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Why 2nd Brightest Castor is alpha Geminorum

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Post by mikemarotta »


"It was originally thought that the stars were assigned labels in alphabetical order according to their brightness. However, in many constellations the brightest star is labelled β, leading astronomers in the 18th century to speculate that many stars had changed in brightness from Bayer’s time. The 19th century German astronomer F. W. A. Argelander discovered that Bayer had used a north-to-south ordering system within magnitude bins.5 Once Bayer had run out of Greek letters, he switched to Latin letters."
5. Babinger, F. 1915, “Johannes Bayer, des Begründer der neuzeitlichen Sternbenennung,” Archiv für die Geschichte der Naturwissenschaften und der Technik, 5, 108

This Month in Astronomical History: September 2020 - "Bayer’s Uranometria" by Jason E. Ybarra, Bridgewater College.
full article here:
https://aas.org/posts/news/2020/09/mont ... ember-2020
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Michael E. Marotta
Astro-Tech 115 mm APO Refractor Explore Scientific 102 mm f/6.47 Refractor Explore Scientific 102 mm f/9.8 Refractor Bresser 8-inch Newtonian Reflector Plössls from 40 to 6 mm Nagler Series-1 7mm. nonMeade 14 mm. Mounts: Celestron AVX, Explore Twilight I Alt-Az, Explore EXOS German Equatorial
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