The Milky Way - Our Galactic Home

The Milky Way: Our Galaxy

The Milky Way is the name of our home galaxy. A galaxy is a huge group of stars, planets, and cosmic dust, all held together by gravity. There are billions of galaxies in the universe, but the Milky Way is special because it is where our solar system lives.

What is in the Milky Way?

The Milky Way contains between 100 and 400 billion stars. Our Sun is just one of these stars! The Milky Way also has planets, space dust, and even very mysterious things like black holes. All the stars you see in the night sky with your eyes are part of the Milky Way.

The Shape and Size of the Milky Way

The Milky Way is a spiral galaxy. It looks a bit like a giant pinwheel, with curving arms spinning out from the center. It is about 100,000 light-years across. A light-year is the distance that light travels in one year—almost 6 trillion miles! Our solar system sits in one of the spiral arms, about 26,000 light-years from the center. In the very center of the Milky Way is a supermassive black hole, which is much bigger than our Sun.

Looking at the Milky Way

When you see a milky, cloudy band of light stretching across the night sky, you are looking through the disk of our galaxy. We are inside the Milky Way, so we can't see its full shape from Earth—just like it's hard to see what a house looks like when you are inside it! The best way to see the Milky Way is from a dark place, far from city lights, on a clear night.

How the Milky Way Moves

The Sun and all the planets in our solar system orbit, or travel around, the center of the galaxy. It takes about 225 million years to go all the way around—this is called a galactic year. Dinosaurs were alive just one galactic year ago!

Our Place in the Universe

Living in the Milky Way is like being one grain of sand on a huge beach. Our solar system is just one tiny speck in a galaxy filled with hundreds of billions of stars!

Interesting Fact: If you could travel as fast as light, it would still take you 100,000 years to cross the Milky Way from one side to the other!