Dr. John Barentine FRAS on Nostr: The globular star cluster Messier 13 earlier tonight. Result of 3600 0.1-sec images ...

The globular star cluster Messier 13 earlier tonight. Result of 3600 0.1-sec images made with my phone and (non-tracking) 20 cm f/3.8 telescope, combined in Siril and the background and color touched up in Gimp. Conditions at my moderately light-polluted site were okay but not great; transparency was poor. The colors of the stars in the image are subtle, just enough to tell the yellowish Red Giant Branch stars from the bluer Horizontal Branch and upper Main Sequence stars.

#Astronomy #Astrophotography #Messier13 #StarCluster