Among the planets in our solar system are bits of rock called asteroids. Too small to be considered planets, asteroids are a “hangover” from the early formation of the solar system, which is about 4.6 billion years old. There are three types of asteroids: the materials that make up their composition determine them.
Type C, or those that contain large amounts of carbon, are the most common, accounting for about 75 percent of asteroids. These gray asteroids are usually made of clay, minerals, and silicate rocks. Type M contains large amounts of metals such as iron and nickel, which probably contribute to its red color. S-types can range in color from red to green and are mainly made up of silicate materials as well as iron and nickel.
As these rocks travel around the sun, they can collide with planets, create falling stars, and form large belts. Here are four amazing facts about asteroids that you may not be familiar with.
1. They can make a big impact
Asteroids collide with planets. Not all of them are extinction level events, but some asteroids have impacted the Earth en masse. About 66 million years ago, a mountain-sized asteroid hit the coast of Mexico’s Yucatan Peninsula, creating the Chicxulub crater. The impact and its damage changed life on Earth and are believed to have contributed to the extinction of the dinosaurs.
The collision caused tsunamis and fires, along with huge amounts of dust and soot. The sulfur from the vaporized rock acidified the oceans and blocked some of the sun, reducing the amount of light reaching the Earth. This inhibited the growth of the plants, leading to a bigger problem in the food chain. There have been other asteroid impact events, the largest ranging from 35 million to more than two billion years ago.
2. They form the asteroid belt
Most known asteroids are located within the asteroid belt, located between the orbits of Mars and Jupiter. According to NASA, the number of known asteroids currently exceeds 1.1 million. They vary in size from as small as dust particles to blocks to thousands of feet in diameter. However, the total collective mass of all asteroids is still less than the mass of the Earth’s Moon.
Although there are millions (if not more) asteroids in the belt, they are very far apart: about 600,000 miles. Therefore, spacecraft can fly through the belt without colliding with any asteroid. In 1973, a spacecraft called Pioneer 10 was the first to cross the asteroid belt.
3. They can become planets
Ceres is the largest object in the asteroid belt and is responsible for one-third of the total mass of the belt. Italian priest and astronomer Giuseppe Piazzi discovered Ceres in 1801, and experts reclassified it from an asteroid to a dwarf planet in 2006.
A dwarf planet is a celestial body that is too large to approach a round shape and orbit the sun. However, they are smaller than real planets and do not have enough gravitational force to accumulate material within their orbits. Ceres is an icy dwarf planet with daytime temperatures of about 100 degrees Fahrenheit negative. At night, it’s even colder, with a staggering 225 degrees negative. There is no atmosphere and one day lasts nine hours. Scientists believe Ceres may have supported life at some point.
4. They may have moons
Some asteroids are large enough to have moons. In 1993, the Galileo spacecraft discovered the first asteroid moon. Ida, an S-type asteroid, has a moon called Dactyl. Since then, several other moons have been discovered orbiting asteroids.
They include a so-called Petit-Prince that is eight miles wide and orbits the asteroid Eugenia. The asteroid Pulcova also has a moon of similar size. Scientists believe that asteroid moons are created from a collision of two asteroids. If the conditions are right, you can cut a piece and send it into orbit. According to NASA, more than 150 asteroids have moons, and some even have two.