Deep Sky
M71
NGC6838

 Globular Cluster
Constellation: Sagetta
Discovered by Philippe Loys de Cheseaux in 1746 and included in Messier's cagalogue in 1780.  M71 is approx 12,00 light-years from us and it spans some 27 light-years.  Z Sagittae, a variable star, calls M71 home.  What I found interesting, is that for a long time M71 was classified as a densley packed open cluster due to its lack of central core and its stars having more metals than usual for an old cluster. Modern phoatometry.... (measures the intensity of objects) has detected a horizontal branch....( what ever that means) but it means enough to reclassify it as a very loosely concentrated gobular cluster, some 9-10 billion years old. -- Lets hear it for this youngster!


10 images
10 sec
9-18-12