Template:Short description Template:Infobox globular cluster
Mayall II, also known as NGC-224-G1, SKHB 1, GSC 2788:2139, HBK 0-1, M31GC J003247+393440 or Andromeda's Cluster, is a globular cluster orbiting M31, the Andromeda Galaxy.
It is located Template:Convert<ref name="Maetal2007"/> from the Andromeda Galaxy's galactic core, and is the brightest<ref name="Maetal2007"/> (by absolute magnitude) globular cluster in the Local Group, with an absolute visual magnitude of −10.94 and the luminosity of 2 million Suns.<ref name=":0" /> It has an apparent magnitude of 13.81 in V band. Mayall II is considered to have twice the mass of Omega Centauri, and may contain a central, intermediate-mass (~ 2Template:E M⊙) black hole.<ref name="Maetal2007"/>
It was first identified as a possible globular cluster by American astronomers Nicholas Mayall and Olin J. Eggen in 1953 using a Palomar Template:Convert Schmidt plate exposed in 1948.<ref name="Maetal2007"/>
Because of the widespread distribution of metallicity, indicating multiple star generations and a large stellar creation period, many contend that it is not a true globular cluster, but is actually the galactic core that remains of a dwarf galaxy consumed by Andromeda.<ref name="Maetal2007"/><ref name="Meylanetal2001">Template:Cite journal</ref>
Origin of namesEdit
- Mayall II is named after Nicholas U. Mayall, who, with Olin J. Eggen, discovered it in 1953.
- SKHB 1 is named for Wallace L. W. Sargent, Charles T. Kowal, F. D. A. Hartwick and Sidney van den Bergh. They also named it G1 in 1977.
- HBK 0-1 is named for John Huchra, J. P. Brodie and S. M. Kent in 1991.<ref name=":0">{{#invoke:citation/CS1|citation
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