Messier 69
Template:Short description Template:Use mdy dates Template:Infobox globular cluster
Messier 69 or M69, also known NGC 6637, and NGC 6634,<ref name=":0">{{#invoke:citation/CS1|citation |CitationClass=web }}</ref><ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> is a globular cluster in the southern constellation of Sagittarius.Template:Efn It can be found 2.5° to the northeast of the star Epsilon Sagittarii and is dimly visible in 50 mm aperture binoculars. The cluster was discovered by Charles Messier on August 31, 1780, the same night he discovered M70. At the time, he was searching for an object described by Nicolas-Louis de Lacaille in 1751–2 and thought he had rediscovered it, but it is unclear if Lacaille actually described M69.<ref name=Thompson2007/>
This cluster is about 28,700<ref name=Kharchenko2013/> light-years away from Earth and Template:Convert from the Galactic Center,<ref name=Piotto2002/> with a spatial radius of 45 light-years.<ref name=approx/> It is a relatively metal-rich globular cluster that is a likely member of the galactic bulge population.<ref name=Heasley2000/> It has a mass of Template:Val with a half-mass radius of Template:Convert,<ref name=Mandushev1991/> a core radius of Template:Convert, and a tidal radius of Template:Convert.<ref name=Kharchenko2013/> Its center has a bright luminosity density of Template:Val·pc−3 (meaning per cubic parsec).<ref name=Piotto2002/> It is a close neighbor of its analog M70 – possibly only 1,800 light-years separates the two.<ref name=Hartmut2011/>
GalleryEdit
- Messier 69 Hubble WikiSky.jpg
As globular clusters go, M69 is one of the most metal-rich on record.<ref name="esa/hubble">Template:Cite news</ref>
- M69map.png
Map showing location of M69
See alsoEdit
References and footnotesEdit
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External linksEdit
Template:Sky Template:Portal bar Template:Messier objects Template:Ngc70