Explanation:
Many stars like our Sun were formed in open clusters.
The
above pictured open cluster,
M25,
contains thousands of stars and is about two thousand
light years distant.
The stars in this cluster all formed together about 90 million years ago.
The bright young stars in
M25
appear blue.
Open clusters,
also called galactic clusters, contain fewer and younger stars than
globular clusters.
Also unlike
globular clusters,
open clusters
are generally confined to the
plane of our Galaxy.
M25 is visible with
binoculars towards the
constellation of the Archer
(
Sagittarius).
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