Meteoroids shed by a comet usually orbit together in a formation called a meteoroid stream. The dusty tail may contain hundreds or even thousands of meteoroids and micrometeoroids. As a comet approaches the sun, the “dirty snowball” of the comet’s nucleus sheds gas and dust. Other meteoroids are the debris that comets shed as they travel through space. This can put the meteoroids on a collision course with a planet or moon. The force of the asteroid collision can throw the meteoroid debris-and sometimes the asteroids themselves-out of their regular orbit. As asteroids smash into each other, they produce crumbly debris-meteoroids. Many meteoroids are formed from the collision of asteroids, which orbit the sun between the paths of Mars and Jupiter in a region called the asteroid belt. The fastest meteoroids travel through the solar system at a speed of around 42 kilometers (26 miles) per second. Different meteoroids travel around the sun at different speeds and in different orbits. Meteoroids are even found on the edge of the solar system, in regions called the Kuiper belt and the Oort cloud.

They orbit the sun among the rocky inner planets, as well as the gas giants that make up the outer planets. Meteoroids, especially the tiny particles called micrometeoroids, are extremely common throughout the solar system. Meteoroids are lumps of rock or iron that orbit the sun, just as planets, asteroids, and comets do.

Definition meteoroid