SOLAR SYSTEM

Detailed explanation-1: -Asteroids, sometimes called minor planets, are rocky, airless remnants left over from the early formation of our solar system about 4.6 billion years ago.

Detailed explanation-2: -M-type (aka M-class) asteroids are a spectral class of asteroids which appear to contain higher concentrations of metal phases (e.g. iron-nickel) than other asteroid classes, and are widely thought to be the source of iron meteorites.

Detailed explanation-3: -Meteoroids are lumps of rock or iron that orbit the sun, just as planets, asteroids, and comets do.

Detailed explanation-4: -Asteroids are bits of building material remaining from the formation of our solar system (for more about solar system formation, check out the YSS topic Birth of Worlds).

Detailed explanation-5: -Most of the asteroids in the main belt are made of rock and stone, but a small portion of them contain iron and nickel metals. The remaining asteroids are made up of a mix of these, along with carbon-rich materials. Some of the more distant asteroids tend to contain more ices.