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

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 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. “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 ... Read full article.