The Leo I Dwarf Galaxy

About This Photograph

Located only a third of a degree away from one of the brightest stars in the sky we find a celestial oddball. Leo I is a dwarf spheroidal galaxy, so named for its small size and oblong shape. At a distance of 900,000 light years, it is thought to be the furthest of the Milky Way's satellite galaxies (i.e., it is in orbit around our galaxy).

The exceedingly bright star in the upper left is Regulus, the brightest star in the constellation Leo. It is actually a triple star system. Both companion stars are visible in this photograph. Locate the two somewhat orange stars to the upper-right of Regulus. This system lies at a distance of about 77.5 light years from Earth. Regulus is much more massive than the sun, and is thus much hotter, giving it its bluish color.

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