Cosmic dust called all the pieces of the cosmic matter. The size of these particles is from a few molecules to 0.1 mm. Scientists believe that cosmic dust is formed not only from collision, destruction of small solids, but also due to the condensation of interstellar gas. Cosmic dust can be distinguished by its origin: the dust is intergalactic, interstellar, and interplanetary and near (usually in the ring system).
Cosmic dust mostly occur in slow-flowing atmospheres of stars are red dwarfs, and explosive processes on the stars and the rapid release of gas from the cores of galaxies. Other sources of education of cosmic dust are planetary and protostar nebula, stellar atmospheres and interstellar clouds.
Whole clouds of cosmic dust that are in the layer of stars forming the milky Way, preventing us to observe a distant star cluster. Such a star cluster like the Pleiades, fully immersed in the dust cloud. The brightest stars that are in this cluster, light dust, as lantern lights at night, the fog. Cosmic dust can Shine only by reflected light.
Blue rays of light passing through cosmic dust, attenuated stronger than red, so the light of the stars, amounting to us, seems to be yellowish or even reddish. Whole areas of the world space remain closed for observation because of cosmic dust.
A day on the Ground settles around 400 tons of cosmic dust.