Asteroids

Asteroids

Asteroids
   
Sixty-Five million years ago, 70 percent of life on Earth died. The most reasonable and possible reason this happened was an asteroid. An asteroid hit the Earth very hard, and in doing this, dirt and dust from the impact stayed in the air and it blocked out sunlight, that's why the dinosaurs died. An asteroid is a rock from outer space. Asteroids have orbited the Sun along with the planets since the solar system formed about 4.6 billion years ago, but it's only been 200 years since we first discovered them. Meteorites are small pieces of asteroids broken off on impact with other asteroids. Most meteorites are rusty brown on the outside, have rounded edges from melting as they go through Earth's atmosphere, and contain iron. There are 3 different types of meteorites: stony, metallic, and stony metallic.92 percents of all asteroids are stone, 6 percent are made of iron and nickel, and the rest are a combination. Some meteorites also contain gold, copper, platinum, and carbon.

Scientists get a good idea of what asteroids are made of by studying them through telescopes.     They can tell what an asteroid is made of by the color and brightness of the asteroid. A lot of asteroids that we have discovered are very dark and made of stone, but there are shiny ones that are made of nickel and iron.

Most big asteroids are ball shaped. Smaller asteroids, which are usually broken off of a larger asteroid, come in a lot of different shapes. All asteroids have craters that form when they bump or crash into other asteroids. The older the asteroid, the more times it has been hit and the more craters it has.

Asteroids can be found orbiting the Sun in a belt between Mars and Jupiter; this is called the Asteroid belt or Main belt. The asteroid belt has been said to probably contain millions of asteroids that are all different. There are more than 20,000 numbered asteroids. Some times asteroids get knocked off the asteroid belt. As asteroids revolve around the...