Image Credit & Copyright: F. Antonucci, M. Angelini, & F. Tagliani, ADARA AstrobralloExplanation: Few star clusters are seen to be so close to each other. Some 7,000 light-years away, though, this pair of open or galactic
star clusters is an easy binocular target,
a lovely starfield in the northern constellation
Perseus. Also
visible to the unaided eye from dark sky areas, it was cataloged in 130 BC by Greek astronomer
Hipparchus. Now known as
h and chi Persei, or
NGC 869 (above right) and
NGC 884, the clusters themselves are separated by only a few hundred light-years and contain
stars much younger and hotter than the Sun. In addition to being physically close together,
the clusters’ ages
based on their individual stars are similar – evidence that both
clusters were likely a product of the same
star-forming region.
