Saturday, March 21, 2015

M7: Open Star Cluster in Scorpius

M7: Open Star Cluster in Scorpius: APOD: 2014 January 7 - M7: Open Star Cluster in Scorpius

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2014 January 7

See Explanation. Clicking on the picture will download the highest resolution version available.
M7: Open Star Cluster in Scorpius

Image Credit & Copyright: Lorand Fenyes
Explanation: M7 is one of the most prominent open clusters of stars on the sky. The cluster, dominated by bright blue stars, can be seen with the naked eye in a dark sky in the tail of the constellation of the Scorpion (Scorpius). M7 contains about 100 stars in total, is about 200 million years old, spans 25 light-years across, and lies about 1000 light-years away. The above deep image, taken last June from Hungary through a small telescope, combines over 60 two-minute exposures. The M7 star cluster has been known since ancient times, being noted by Ptolemy in the year 130 AD. Also visible are a dark dust cloud and literally millions of unrelated stars towards the Galactic center.