Space weathering is the type of weathering that occurs to any object exposed to the harsh environment of outer space. Bodies without atmospheres take on many weathering processes:collisions of galactic cosmic rays and solar cosmic rays, irradiation, implantation, and sputtering from solar wind particles, and bombardment by different sizes of meteorites and micrometeorites.

Weathering is the deterioration of rocks, soils and minerals through contact with water, atmospheric gases, sunlight, and biological organisms. Weathering occurs in situ, and so is distinct from erosion, which involves the transport of rocks and minerals by agents such as water, ice, snow, wind, waves and gravity.