Cosmic dust

Found all throughout the Universe, cosmic dust or spacedust represents the remaining visible matter in space not collected into molecular clouds or planets and stars. Space dust may form dust clouds, but can be found everywhere, including the interstellar medium.

This dust is exceptionally small - much smaller than planetary dust that is typically fine bits of fabric, dirt, or dead biological matter. These tiny, irregularly shaped particles range from less than 1/100th of a micron to 10 microns in size, with each micron representing one millionth of a meter. For comparison a particle of smoke is about 1/10th of a micron large. They are comprised of carbon compounds and additional materials that include silicon, oxygen, nitrogen, nickel and other heavy elements. Because of its carbon content, this cosmic fluff has been compared to diamond dust.

Cosmic dust originates from red giant stars and supernovae, although there are other sources. It's created when material from the core of a dying star is expelled into surrounding space as grains of heavy elements that forms into a cloud of debris. Over time, these particles drift from the scene of their creation, mix with the hydrogen and helium suspended throughout space, are incorporated into the vast clouds that later incubate new stars and coalesce to form the planets with circle them. These seemingly insignificant free floating grains are responsible for much of the worlds we see around us, as well as their inhabitants.

To counter the hazard of stray dust particles penetrating starship hulls as they move through space at relativistic speeds, several types of anti-particle shielding systems have been developed, and are used in almost all modern spacecraft.