asteroïdes

Asteroids are rocky, airless remnants left over from the early formation of our solar system, about 4.6 billion years ago. They are also sometimes called minor planets. The vast majority of asteroids are found in the asteroid belt, a region between the orbits of Mars and Jupiter. However, some asteroids have orbits that take them closer to Earth, and these are known as near-Earth asteroids.

Asteroids vary greatly in size. Some are as small as pebbles, while others can be hundreds of kilometers in diameter. The largest known asteroid is Ceres, which is about 940 kilometers (585 miles) across and is so large that it is also classified as a dwarf planet. Scientists study asteroids to learn more about the conditions and processes that led to the formation of the planets. Asteroids can also pose a threat to Earth. While the chances of a large impact are very small, a significant impact could have devastating consequences. Space agencies are developing methods to detect and potentially deflect asteroids that might be on a collision course with our planet.