Image of Betelgeuse from the Atacama Large Millimeter/submillimeter Array (O'Gorman et al. 2017). Credit: ALMA (ESO/NAOJ/NRAO) E. O’Gorman P. Kervella

Sunday, December 13, 2020
4:00 to 5:30 pm Eastern Standard Time
(1:00 to 2:30 pm Pacific Standard Time)

On December 13, 1920, the first measurement was made of the angular diameter of the red supergiant star Betelgeuse. This marked the first successful size estimate for any star other than the Sun (Michelson & Pease 1921, ApJ, 53, 249).

Please join us for an on-line event to mark the 100th anniversary of this seminal advance in astrophysics. The celebration will include presentations by Hal McAlister (Georgia State University) and David DeVorkin (Smithsonian Institution), a look at the beam interferometer that accomplished this feat, and a toast to Michelson, Pease, Anderson and Kimple.

The meeting will be hosted by Douglas Gies (GSU) on the Webex platform.  Webex runs under most browsers or you can download the application here:


Meeting number: 120 600 5370

Join by video system:
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Join by phone:
+1-415-655-0002 US Toll
Access code: 120 600 5370

A recording of the event is available at the following location:
Video recording of Betelgeuse Centenary Celebration