# Astronomy 101

**05 Galaxies**

Galaxies are massive groupings of stars and gas and dust. Our sun is in the **Milky Way **galaxy, which measures approximately 100,000 light years across.

Our spiral galaxy is made up of several billion stars. Sobering. Want something more sobering?

The Milky Way is one galaxy that has hundreds of billions of stars. Again, we are one galaxy.

And there are at least a few hundred million galaxies in the universe. Each with hundreds of billions of stars.

Think on that.

Think the world still revolves around you and your problems?

You are tiny. So am I.

**Spiral**

Yeah, that’s us. Galaxies that have spiral arms coming out from the center. Our solar system is on one of the spiral arms of the Milky Way. Good thing we’re on an arm and not the center. What’s in the center?

A big black hole.

**Elliptical**

Elliptical galaxies are shaped like a big egg.

**Irregular**

These are pretty much every kind of galaxy that’s shaped differently than a spiral or elliptical.

Again, we are one galaxy.

One galaxy of many, many, many, many, many, many, many, many, many, many,

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many, many, many, many, many, many, many, many, many, many, many, many, many,

galaxies.