Astronomy Picture of the Day

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.

2012 September 12
See Explanation.  Clicking on the picture will download
 the highest resolution version available.

M7: Open Star Cluster in Scorpius
Image Credit & Copyright: Dieter Willasch (Astro-Cabinet)

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 exposure was taken from Hakos Farm in Namabia. 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.

Tomorrow's picture: pixels in space


< | Archive | Index | Search | Calendar | RSS | Education | About APOD | Discuss | >

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
NASA Web Privacy Policy and Important Notices
A service of: ASD at NASA / GSFC
& Michigan Tech. U.