NEBULAE & STAR CLUSTERS A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z           HOME ABOUT CATEGORIES SITE MAP COPYRIGHT ADVERTISE CONTACT entire Web this site Butterfly Cluster (M6, NGC 6405) Credit: AURA, NOAO, NSF An open cluster in the constellation Scorpius, 4° northwest of M7 (Ptolemy's Cluter), that contains about 80 stars roughly in the shape of a butterfly. Visible to the naked eye, it was first noted by Giovanni Hodierna before 1654. Its most conspicuous star is an orange giant K star of magnitude 6.2. visual magnitude 5.3 angular size 25' diameter 20 light-years age about 50 million years distance 2,000 light-years position R.A.17h 40.1m, Dec. -32° 13' Related categories    • NEBULAE AND STAR CLUSTERS    • MESSIER CATALOGUE Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) BACK TO TOP