Our sun is one of a massive collection of stars in the Milky Way galaxy, while every star orbits the center of the galaxy.
But these hundreds of billions of stars are not the only big things orbiting the center of the galaxy. A whole galaxy can orbit the center of another bigger galaxy.
Astronomers call these kinds of galaxies, Satellite Galaxies.
Where Can We Find Them?
Look no further than our galaxy. The Milky Way has not one, but a number of satellite galaxies, but the biggest one is the Large Magellanic Cloud. It is about 163,000 light-years away and around 1/100th the size of the Milky Way. Unlike our spiral galaxy, this one lacks a clean spiral shape. Some scientists think that is because the Milky Way and other galaxies are pulling and warping it.
Astronomers consider a small group of stars a dwarf galaxy.
When it comes to distance, there are two contenders for closest satellite galaxy. Astronomers consider a small group of stars a “dwarf galaxy”. The other group is so close and there is a big debate going on whether or not it is part of our galaxy or its own dwarf galaxy.
Astronomers have named the one that everyone agrees on the Sagittarius Dwarf Spheroidal Galaxy. It’s about 50,000 light-years away from the Milky Way center. It orbits over the top and down below the disk of our galaxy, like a ring over a spinning top.
But there is something even closer to our Milky Way—a cluster of stars named by some to be the Canis Major Dwarf Galaxy. Scientists estimate that it contains around a billion stars. It is so close to the edge of the Milky Way that it is closer to our solar system than to our galaxy’s center. It’s about 25,000 light-years away from us.