[Rockhounds] Most Carbon-Rich Asteroids Never Make It to Earth—and Now We Know Why

[Kreigh Tomaszewski]

Earth’s meteorite collection just got called out for being a little
biased—and what’s more, a team of astronomers pinpointed exactly why that
bias occurs.

Carbonaceous asteroids are all over our solar system, both in the main belt
and closer to Earth. But very few of the carbon-rich rocks are actually
found *on* Earth, comprising just 4% of the meteorites recovered on our
planet’s surface.

The astronomical team wanted to understand what causes the discrepancy.
Their findings, published
<https://www.nature.com/articles/s41550-025-02526-6> today in Nature
Astronomy, indicate that carbon asteroids get obliterated by the Sun and
Earth’s atmosphere before they can make it to ground.

“We’ve long suspected weak, carbonaceous material doesn’t survive
atmospheric entry,” said Hadrien Devillepoix, a researcher at Australia’s
Curtin Institute of Radio Astronomy and co-author of the paper, in a
university release
<https://www.curtin.edu.au/news/media-release/scientists-may-have-solved-a-puzzling-space-rock-mystery/>.
“What this research shows is many of these meteoroids don’t even make it
that far: they break apart from being heated repeatedly as they pass close
to the Sun.”

The team analyzed nearly 8,000 meteoroid impacts and 540 potential falls
from 19 different observation networks around the globe to understand why
carbonaceous asteroids are so rare on Earth.

https://gizmodo.com/most-carbon-rich-asteroids-never-make-it-to-earth-and-now-we-know-why-2000588954