4 min

Chapter 7: Whirlpool Galaxy (M51‪)‬ NASA's Touch the Invisible Sky Audio Podcasts

    • Natural Sciences

Galaxies are collections of millions to billions of stars gravitationally bound together. Galaxies come in different shapes and sizes, and fall into three broad categories: spiral (shaped like a pinwheel), elliptical (like a ball, sometimes round and sometimes squashed) and irregular, with no obvious shape or structure. Our own Milky Way galaxy is a spiral.

Galaxies are collections of millions to billions of stars gravitationally bound together. Galaxies come in different shapes and sizes, and fall into three broad categories: spiral (shaped like a pinwheel), elliptical (like a ball, sometimes round and sometimes squashed) and irregular, with no obvious shape or structure. Our own Milky Way galaxy is a spiral.

4 min

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