[Rockhounds] The 'cosmic dust' sitting on your roof

[Kreigh Tomaszewski]

It's in the dirt on the ground, the debris on your roof, and the dust that
tickles your nose – tiny pieces of "cosmic dust", everywhere.

These microscopic particles from outer space are micrometeorites – mostly
the debris from comets and asteroids – and they have settled all over our
planet.

The dust, scientists are learning, contains clues to how Earth and our
Solar System formed. But while the stuff is everywhere, finding in amongst
the dirt and debris is far from straightforward.

Most cosmic dust probably comes the Zodiacal cloud
<https://doi.org/10.1186/BF03352135>, an interplanetary dust cloud that
orbits our Sun. Earth passes through this cloud, and the cosmic dust is
swept up by our planet's atmosphere.

Once the particles settle to the ground, they can be found anywhere; they
could be sitting on your clothes right now. But despite their widespread
presence, finding cosmic dust isn't easy.

One place that the particles show up more easily is Antarctica. Around a
decade ago, Matthew Genge at Imperial College London spent seven weeks
searching for and collecting dust there, as part of the Antarctic Search
for Meteorites program (Ansmet), a US-led field-based science project that
recovers meteorite specimens. Since then, he's spent years analysing the
materials he found on this trip.

"Sometimes I feel like it's a bit like the emperor's clothes, I've spent my
life studying something no one can see," Genge says.

Antarctica may seem like a long way to travel just to sweep up some dust,
but it's the perfect place to go if you're looking for cosmic material.
"It's the driest place on Earth because all the water that is there is ice.
And that means that the cosmic dust and meteorites last a long time," Genge
says.


https://www.bbc.com/future/article/20230915-the-cosmic-dust-sitting-on-your-roof