I recently imaged this gem. NGC 6934 (also known as Caldwell 47) is a globular cluster of stars in the northern constellation of Delphinus, about 52 thousand light-years from the Sun.
Globular clusters are odd beasts. They aren’t galaxies, but like galaxies, they are a gravitationally bound collection of stars. They can contain millions of stars densely packed together, and they are old. Really old. They likely formed when the universe was only about 400 million years old. But the details of their origins are still unclear.
We know globular clusters are old because they don’t exhibit any star production, and the stars they contain are old, low-metal stars. This suggests that the clusters formed during the early star-formation period of the universe, and have long since depleted or cast off the dust and gas to form new stars. The stars of a globular cluster have similar ages and chemical compositions, which suggests a globular cluster formed from a single large molecular cloud.
https://www.universetoday.com/161394/new-clues-to-the-formation-of-globular-clusters-their-ultramassive-stars/
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