Looking like diamonds in the sky, this lovely astrophoto shows Ptolemy’s Cluster, or Messier 7, a very bright open star cluster easily visible with the naked eye near the tail of Scorpius. Taken by photographer Rolf Wahl Olsen — Sky Viking on Flickr — this beautiful, glittering cluster is about 980 light years away from … Continue reading "Astrophoto: Ptolemy’s Cluster by Rolf Wahl Olsen"