Give Now  »

wfiu logo
WFIU Public Radio

wtiu logo
WTIU Public Television

Choose which station to support!

Indiana Public Media | WFIU - NPR | WTIU - PBS

Noon Edition

What Is The Difference Between Comets And Asteroids?

Comet Hale Bop

In past episodes we have explained that comets come from the Kuiper Belt and the Oort Cloud. But asteroids are different. Whereas a comet is essentially a mass of dirty ice, asteroids are more like giant rocks. Or, if you like, tiny planets.

Asteroids come in many sizes, and most won't have sufficient gravity to make them spherical. Recent studies have shown they look more like battered potatoes. Almost all orbit the sun in a ring-shaped region between Mars and Jupiter called the "Main Belt." On occasion one may collide with a planet, thoughin which case, watch out! Even a smallish asteroid can pack a wallop.

Support For Indiana Public Media Comes From

About A Moment of Science