Dwarf Galaxy Leo I

Leo I is a dwarf spheroidal galaxy located in the constellation of Leo. It’s a member of the Local Group of galaxies, and astronomers think that it’s one of the distant satellite galaxies of the Milky Way, measuring about 820,000 light-years away from the Milky Way.

Astronomers have calculated that Leo I has a mass of about 20 million solar masses. Compare that to our own Milky Way which is thought to have about 600 million solar masses. As with many dwarf galaxies, Leo I has a very low metallicity (the presence of elements heavier than hydrogen and helium). It also has a very low rate of star formation. In fact, it seems to have completely stopped about 200-500 million years ago.

Leo I is located close to the bright star Regulus, so it’s often referred to as the Regulus Dwarf. In fact, scattered light from Regulus makes it difficult to observe Leo I.

We have written many articles about dwarf galaxies for Universe Today. Here’s an article about an almost invisible companion galaxy to the Milky Way. And here’s an article about the closest galaxy to the Milky Way.

If you’d like more info on galaxies, check out Hubblesite’s News Releases on Galaxies, and here’s NASA’s Science Page on Galaxies.

We have also recorded an episode of Astronomy Cast about galaxies – Episode 97: Galaxies.