Globular Cluster M22 from CFHT
Explanation:
The globular cluster
M22,
pictured
above, contains over 100,000 stars.
These stars formed together and are gravitationally bound.
Stars
orbit the center
of the cluster, and the cluster orbits the
center of our Galaxy.
So far, about
140 globular clusters are known to exist in a roughly
spherical halo around the
Galactic center.
Globular clusters
do not appear spherically distributed as viewed from the Earth,
and this fact was a key point in the
determination that our Sun
is not at the center of
our Galaxy.
Globular clusters are very
old.
There is a straightforward method of
determining their age, and this nearly matches the
13.7 billion-year age of our
entire universe.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.
