M9 is one of the globular clusters closest to the center of the Milky Way Galaxy, only around 5,500 light-years from the galactic core. It’s about 25,800 light-years from Earth.
M9 has an apparent magnitude of 7.9, an angular size of 9.3′, and can be viewed with a small telescope. It is one of the nearer globular clusters to the center of the galaxy as is around 5,500 light-years from the Galactic Core. Its distance from Earth is 25,800 light-years.
The total luminosity of this cluster is around 120,000 times that of the Sun. It has an apparent magnitude of 7.9, so it can be viewed with a small telescope.
Say, “M9,” to a soldier, and he’ll think of a Beretta pistol. Say, “M9,” to an astronomer, and he’ll think of this star cluster. Charles Messier described the 9th entry in his astronomical catalog as “Nebula, without star, in the right leg of Ophiuchus …”. But Messier 9 (M9) does have stars, known to modern astronomers as a globular cluster of over 300,000 stars within a diameter of only about 90 light-years. It lies some 25,000 light-years distant, near the central bulge of our Milky Way galaxy. This Hubble Space Telescope close-up resolves the dense swarm of stars across the cluster’s central 25 light-years. The stars are at least twice the age of the Sun and deficient in heavy elements. The stars’ colors correspond to their temperatures. Redder stars are cooler, bluer stars are hotter. Many of the cluster’s cool red giant stars show a yellowish tint in this sharp Hubble view.