M56

Messier 56 (also known as M56 or NGC 6779) is a globular cluster in the constellation Lyra. M56 is about 32,900 light-years away from Earth and measures roughly 84 light-years across, containing 230,000 solar masses (M☉). It is about 31–32 kly (9.5–9.8 kpc) from the Galactic Center and 4.8 kly (1.5 kpc) above the galactic plane. This cluster has an estimated age of 13.70 billion years and is following a retrograde orbit through the Milky Way. The properties of this cluster suggest that it may have been acquired during the merger of a dwarf galaxy, of which Omega Centauri forms the surviving nucleus. For Messier 56, the abundance of elements other than hydrogen and helium, what astronomers term the metallicity, has a very low value of [Fe/H] = –2.00 dex which is 1⁄100 of the abundance in the Sun. The brightest stars in M56 are of 13th magnitude, while it contains only about a dozen known variable stars, such as V6 (RV Tauri star; period: 90 days) or V1 (Cepheid: 1.510 days). In 2000, a diffuse X-ray emission was tentatively identified coming from the vicinity of the cluster. This is most likely interstellar medium that has been heated by the passage of the cluster through the galactic halo. The relative velocity of the cluster is about 177 km s−1, which is sufficient to heat the medium in its wake to a temperature of 940 000 K. M56 is approaching us with the high velocity of 145 km/s. Photographed with the RC8" reflector telescope and the ASI 2600MC CMOS color camera in Stuvsta, September 14th, 2024. Exposure was 40 * 2 min with IDAS LPS P3 light pollution filter. Postprocesssing in Pixinsight with Blur XTerminator.