Credits: Keith Turnecliff, Nerja, Spain
Located 27,000 light-years from Earth in the constellation Hercules, this globular cluster — a ball of stars that orbits our galaxy’s core like a satellite —
was first discovered by the German astronomer Johann Elert Bode in 1777.
With an apparent magnitude of 6.3, M92 is one of the brightest globular clusters in the Milky Way and is visible to the naked eye under good observing conditions. The cluster is very tightly packed with stars, containing roughly 330,000 stars in total.
As is characteristic of ancient globular clusters — of which M92 is one of the oldest — the predominant elements within M92 are hydrogen and helium, with only traces of others, so it belongs to a group of metal-poor clusters. To astronomers, metals are all elements heavier than hydrogen and helium.
Messier 92 (also known as M92, or NGC 6341) is a globular cluster of stars in the northern constellation of Hercules. It was discovered by Johann Elert Bode in 1777, then published in the Jahrbuch during 1779. The cluster was independently rediscovered by Charles Messier on March 18, 1781 and added as the 92nd entry in his catalogue. M92 is at a distance of about 26,700 light-years away from Earth.
Facts about M92 by Keith Turnecliff
M92 is one of the brighter globular clusters in the northern hemisphere, but it is often overlooked by amateur astronomers because of its proximity to the even more spectacular Messier 13.
It is visible to the naked eye under very good conditions.
It can be most easily spotted during the month of July.