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. 2004 February
22 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 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. This color picture was taken
in 1995 at the Burrell-Schmidt Telescope at Kitt Peak National
Observatory in Arizona. The M7 star cluster has been known since
ancient times, being noted by Ptolemy in the year 130 AD. Also
visible is a dark dust cloud near the bottom of the frame, and
literally millions of unrelated stars towards the Galactic
center. Authors & editors: NASA Web Site Statements, Warnings,
and Disclaimers NASA Official: Jay Norris. Specific rights
apply. A service o