• Skip to primary navigation
  • Skip to main content
  • Skip to footer
Zippy Facts Logo

Zippy Facts

Interesting Random Facts

  • Animals
  • Culture
  • Firsts
  • Food
  • Geography
  • Health
  • History
  • Inventions
  • Language
  • Mythology
  • Odds
  • People
  • Religion
  • Science
  • Space
  • Universe
  • World
You are here: Home / Space / What Is the Difference Between Planets, Planetesimals, and Asteroids, and How Did the Kuiper Belt Get Its Name?

What Is the Difference Between Planets, Planetesimals, and Asteroids, and How Did the Kuiper Belt Get Its Name?

July 18, 2020 by Karen Hill

Some comets may come from the Kuiper Belt, but most probably originate in the Oort Cloud.

The celestial bodies in the Kuiper Belt, however, prompt debate over the differences between planets, planetesimals, and asteroids.

Astronomer Gerard Kuiper studied the satellites of the outlying planets and, in the 1940s, discovered the moons Miranda and Nereid of Uranus and Neptune, respectively.

He proposed the existence of a group of celestial bodies beyond the orbit of Neptune, later named the Kuiper Belt.

Are these bodies asteroids, planetesimals, or planets? It is sometimes hard to say, since their composition, sizes, and orbits are loosely similar.

Some astronomers question whether the planet Pluto and Uranus’s moon Triton aren’t in fact just large planetesimals, leftover material from the planets’ formation.

A number of asteroids from the Kuiper Belt, such as Pholus and 1992 QB, discovered in 1992, have eccentric orbits, and may be considered planetesimals.

The fine lines between the definitions of these celestial bodies leave ample room for discussion.

Related Facts

  • Where Do Comets Come From and Where Are the Oort Cloud and the Kuiper Belt Located In the Solar System?
  • How Many Minor Planets Are There In Our Solar System and Where Are the Main Belt Asteroids Located?
  • What are the differences between comets, asteroids, and meteors?
  • Who Discovered the laws of planetary motion and that planets orbit around the sun in ellipses?
  • What Are Minor Planet Asteroids Made of and What Is the Difference Between C-Type and M-Type Asteroids?
  • How Does the Moon Always Keep the Same Face Toward Earth?

Filed Under: Space

About Karen Hill

Karen Hill is a freelance writer, editor, and columnist. Born in New York, her work has appeared in the Examiner, Yahoo News, Buzzfeed, among others.

Previous Post: « Where Do Comets Come From and Where Are the Oort Cloud and the Kuiper Belt Located In the Solar System?
Next Post: Why Is a Comet’s Tail Sometimes In Front of the Comet and How Big Was the Great Comet of 1811? »

Footer

Follow

  • Facebook
  • Flickr
  • GitHub
  • Google+
  • Instagram
  • LinkedIn
  • Medium
  • Pinterest
  • StumbleUpon
  • Tumblr
  • Twitter
  • YouTube

Categories

Accomplishments Animals Culture Firsts Food Geography Health History Inventions Language Mythology Odds People Religion Science Space Universe World Your Body

About

Zippy Facts empowers the world by serving educational content that is accessible to everyone.

A tribute to growing up, zippyfacts.com showcases interesting and unusual facts about the world.

Our mission is to use technology to facilitate knowledge transfer and sharing.

Copyright © 2020 Zippy Facts

  • About Us
  • Contact
  • Privacy Policy