Asteroids, Comets, and Meteors: A Celestial Guide
Near Earth Asteroids (NEAs)
Asteroids that cross the orbits of inner planets.
Comets
Icy counterparts to asteroids, formed beyond the frostline.
Kuiper Belt
Objects outside the orbit of Neptune to the beginning of the Oort Cloud.
Asteroids
- Small, naturally formed solid bodies that orbit the Sun.
- Airless and show no detectable outflow of gas or dust.
- 18 different compositional types, ranging from solid metal to soggy dirt clods.
- Most are"rocky" consisting of common minerals and free metal. -"Iron" composed of almost pure metal (mostly iron and nickel). -"Carbonaceous Chondrite" composed of rocky material and carbon-rich compounds.
Asteroid Facts
- Rocky leftovers of planet formation.
- Largest is Ceres, diameter ~1,000 km.
- 150,000 in catalogs, and probably over