|
Mayall II (M31 G1) 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 130,000 light-years (40 kpc)〔 from Andromeda's galactic core, and is the brightest〔 (absolute magnitude) globular cluster in the Local Group, having an apparent magnitude of 13.7. G1 is considered to have twice the mass of Omega Centauri. G1 may contain a central, intermediate-mass (∼ 2 M⊙) black hole.〔 It was first identified as a possible globular cluster by Nicholas Mayall & O.J. Eggen in 1953 using a Palomar 48-inch Schmidt plate exposed in 1948.〔 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.〔 ==Origin of names== Mayall II is named after Nicholas U. Mayall, who, with O.J. Eggen, discovered it in 1953. SKHB 1 is named for Wallace L. W. Sargent, C.T. Kowal, F.D.A. Hartwick, and Sidney van den Bergh. They also named it G1 in 1977. HBK 0-1 is named for J.P. Huchra, J.P. Brodie, and S.M. Kent in 1991. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Mayall II」の詳細全文を読む スポンサード リンク
|