Asteroids aren’t the only things that hit Earth. Each day, more than 100 tons of material from asteroids and comets falls toward Earth. Most of it is destroyed by friction as it passes through our atmosphere. If something DOES hit the ground, it is known as a meteorite.
While asteroid impacts were more common in the past, they aren’t as frequent today.
Earth suffers an impact from an object the size of a football field about once every 2,000 years.
A car-sized meteoroid (a piece of asteroid) falls into Earth’s atmosphere about once a year. The result is a beautiful fireball, but the meteoroid usually burns up before reaching the ground.
Some asteroids are actually blown-out comets. The ices are gone, and all that’s left is the rocky material
Some asteroids have moons of their own!
Most asteroids orbit the Sun in the Asteroid Belt, which lies between Mars and Jupiter.
Asteroids are also referred to as minor planets or planetoids.
Asteroids are rich in precious metals and other metals, as well as water.
The nucleus of a comet is made of ice and can be as small as a few meters across to giant boulders a few kilometers across.
As a comet gets closer to the Sun, it begins to experience heat. That causes some of its ices to sublimate (similar to dry ice sizzling in sunlight). If the ice is close to the comet’s surface, it may form a small “jet” of material spewing out from the comet like a mini-geyser.
Comets have two tails: a dust tail (which you can see with the naked eye) and a plasma tail, which is easily photographed but difficult to see with your eyes.