100 years ago tonight, Edwin Hubble made the astronomical observation that definitively established the existence of the #universe beyond our own Milky Way galaxy. 

His discovery of a Cepheid variable #star in the Andromeda Galaxy — famously labeled "VAR!" with red ink in Hubble's own hand on the plate — demonstrated beyond a doubt that Andromeda was a separate #galaxy from our own.

Read more on the Carnegie Observatories site: https://obs.carnegiescience.edu/PAST/m31var

#Astronomy #History

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 What's That Huge Red Blob In The Night Sky?

This image was made by Bill Dunford (NASA JPL) at McDonald Observatory last Friday night. The red blob appears to be an induced aurora from a rocket launch, likely the 2nd stage burn of the #Falcon9 #Starlink 6-16 launch out of Canaveral at 0338 UTC on the 16th. Coincidentally, the 2.7m telescope, equipped with an IFU spectrograph, was looking in the direction of this spot as it passed overhead. It's not known yet whether the light affected the data.

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 Virtual registration for #IAU Symposium 385 on #astronomy and satellite constellations is closing on Monday, 17th September. Please consider attending this informative and dynamic event!

The full symposium program is now available on: https://research.iac.es/congreso/iaus385/pages/symposium/programme.php

#Conferences #Space #SpaceSustainability

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