Asteroids, or Minor Planets

Types of Asteroids Like meteoroids, Minor Planets or Asteroids are divided into three kinds by composition: Iron-nickel Silicate (Stony) Carbonaceous They are not distributed evenly. Silicate ones orbits closer to the Sun and Carbonaceous ones` farther out.

Groups of Asteroids Asteroids can also be divided into groups based on where they orbit: Apollo: These asteroids orbit closer to the Sun. Within the orbit of Mars. Many cross Earth’s orbit and may strike Earth. The largest, Sisyphus, is 10 km in diameter, is about the same size as the one that wiped out the Dinosaurs

The Asteroid Belt between Mars and Jupiter contains by far the most asteroids. The larger Asteroids form Kirkwood gaps The Trojan asteroids orbit on Juptier’s orbit. Trapped by Jupiter’s & the Sun’s gravity They are divided into two “camps” The Greeks 60° in front, and the Trojans, 60° behind Jupiter

The Centaur asteroid group. (in Orange) Orbits between Jupiter and Neptune Many crossing Saturn’s and Uranus’ orbits Unlike other asteroids They have an comet like composition The largest are Chiron and Chariklo at about 230Km and 260 km diameters respectively

In March 2014 Chariklo became the first asteroid known to have… Rings

Another Dwarf Planet? Vesta is the second largest (at about 600km diameter) asteroid in the asteroid belt. The Space probe “Dawn” visited it and Ceres to determine if it is a Dwarf Planet or not. It has been determined not to be

Ida and Dactyl Ida was the first Asteroid to be discovered that has a … Moon! Tiny Dactyl