Fabricating the invisible: cosmic dust, meteors, magic amulets and nano messages

Cosmic dust

also called extraterrestrial dust, space dust, or star dust – is dust that occurs in outer space or has fallen onto Earth. Most cosmic dust particles measure between a few molecules and 0.1 mm (100 μm), such as micrometeoroids. Larger particles are called meteoroids. Cosmic dust can be further distinguished by its astronomical location: intergalactic dust, interstellar dust, interplanetary dust (as in the zodiacal cloud), and circumplanetary dust (as in a planetary ring). There are several methods to obtain space dust measurement.

In the Solar System, interplanetary dust causes the zodiacal light. Solar System dust includes comet dust, planetary dust (like from Mars),asteroidal dust, dust from the Kuiper belt, and interstellar dust passing through the Solar System. Thousands of tons of cosmic dust are estimated to reach Earth's surface every year, with most grains having a mass between 10−16 kg (0.1 pg) and 10−4 kg (0.1 g).

Cosmic dust contains some complex organic compounds (amorphous organic solids with a mixed aromatic–aliphatic structure) that could be created naturally, and rapidly, by stars. A smaller fraction of dust in space is "stardust" consisting of larger refractory minerals that condensed as matter left by stars.

Hunting for micrometeoroids

60 tonnes of comsic dust falls on the surface of the earth. We can find an average of 1x1m2 micrometeoroids on the ground per day Having magnetic proprities we can hunt for them using neodyne magnets.

Their size is between 100 - 500 μm (just a bit bigger than the diameter of a hair).

For a good explanation check here:
Ref: https://www.youtube.com/watch?v=B2ww3FSdKwg
Mircometeorites database https://www.micrometeorites.org/database

The oldest matter we can touch

Meteorites are the oldest elements that we can touch on earth, the primitive metorites (rare) are constituted of grains of dust that preced the formation of the plantes. Most of the metorite families that fall on earth come form the asteroide belt and were formed with the stars of our solar system 5billion years ago. They have know the volcanique activity so they help us understanding how plantes have formed.