Cosmic Dust

The Universe is a very dusty place, filled with cosmic dust that permeates every part of the cosmos, which stems from the Big Bang, Super Nova explosions and includes debris falling off of comets.  Cosmic dust is also called stardust, extraterrestrial dust and space dust, and it is the dust particles (microscopic grains of matter) that exist in outer space, the solid material that floats around in the space between the stars as well as the interstellar dust which lands on planet Earth.  Most cosmic dust particles are between a few molecules to 0.1 µm in size.  The Earth is a dirty place, and we aren’t getting much help from space. Cosmic dust is not the same as the dust you find in your house, it is more like smoke.  Every day, incredibly small dust particles from meteorites, comets, and other 4.6 billion-year-old pieces of our solar system fall into the Earth’s atmosphere. Researchers recently figured out that about 60 tons of cosmic dust falls to Earth every day.

Grains of cosmic dust play an important role in the origin of planetary systems and possibly even that of life itself.  Most of the dust in interstellar space comes from stars that have moved off the main sequence and entered the red giant phase of their evolution.  These stars have extended atmospheres rich in silicon, oxygen, and carbon, these elements were manufactured in the stellar core, but they have been dredged to the surface by convection currents.  Depending on its life history, a red giant may have surface layers that are rich in either carbon or oxygen.  A carbon star gives rise to a dense pall of carbon particles, in the form of graphite flakes or amorphous lumps, each measuring about 0.01 microns across.  In the case of an oxygen-rich star, the oxygen atoms react with silicon and any metal atoms in the star’s atmosphere to form silicate grains, roughly 1 micron across.  As the grains are blown away from the star by radiation pressure and their temperature falls, they begin acquiring additional atoms of hydrogen, oxygen, carbon, nitrogen, and sulfur, which have also escaped from the parent star.  These accreted (process where particles accumulate materials into a massive object by gravitationally attracting more matter) build up into icy mantles of water ice and solid ammonia, methane, and carbon dioxide.

Cosmic Charlie – Grateful Dead – 1/2/70 Fillmore East

Written for Mindlovemisery’s Menagerie Tale Weaver No 148….Dust

11 thoughts on “Cosmic Dust

  1. Wow Jim but once again you educate me…60 tons of dust a day? We live in a wondrous world don’t we….thanks so much for adding your thoughts to this week’s tale weaver.

    Liked by 1 person

Comments are closed.