meteoroid

Small natural object in interplanetary space. Meteoroids are smaller than asteroids, ranging from the size of a pebble up, and move through space at high speeds. There is no official distinction between meteoroids and asteroids, although the term ‘asteroid’ is generally reserved for objects larger than 1.6 km/1 mi in diameter.

Meteoroids are believed to result from the fragmentation of asteroids after collisions. Some meteoroids strike the Earth's atmosphere, and their fiery trails are called meteors. If they fall to Earth, they are named meteorites.

A meteoroid could puncture a spacecraft or spacesuit. The Skylab space station carried a meteoroid shield, and a protective layer of felt was added to the spacesuits of astronauts on the Gemini project.