Messier 32 (also known as M32 and NGC 221) is a dwarf "early-type" galaxy about 2,490,000 light-years (760,000 pc) from the Solar System, appearing in the constellation Andromeda. M32 is a satellite galaxy of the Andromeda Galaxy (M31) and was discovered by Guillaume Le Gentil in 1749.
The galaxy is a prototype of the relatively rare compact elliptical (cE) class. Half the stars are concentrated within the inner core, which has an effective radius of 330 light-years (100 pc). Densities in the central stellar cusp increase steeply, exceeding 3×107 M☉ pc−3 (30 million solar masses per cubic parsec) at the smallest sub-radii resolved by Hubble Space Telescope, and the half-light radius of this central star cluster is around 6 pc (20 light-years). Like more ordinary elliptical galaxies, M32 contains mostly old faint red and yellow stars with practically no dust or gas and consequently no current star formation. It does, however, show hints of star formation in the relatively recent past.
High Density: It features an extremely dense core, with half of its total stars packed into a central radius of just a few hundred light-years. Black Hole: A supermassive black hole sits at its center, with an estimated mass between 1.8 and 5 million solar masses
Astronomers believe M32 may be the surviving, compressed core of a much larger galaxy. Billions of years ago, this progenitor galaxy experienced a close encounter or collision with the Andromeda Galaxy, stripping away its outer stars and leaving behind the compact object we see today.
This Hubble image of Messier 32 was taken as part of the Panchromatic Hubble Andromeda Southern Treasury (PHAST) that created a legacy map of the southern half of M31 (the Great Andromeda Galaxy) in visible and near-ultraviolet light.
NASA, ESA, B. Williams (University of Washington); Image Processing: Gladys Kober (NASA/Catholic University of America
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