Dust from a giant asteroid crash caused an ancient ice age

ScienceDaily | Sep 18, 2019 at 6:30 PM
  • There’s always a lot of dust from outer space floating down to Earth, little bits of asteroids and comets, but this dust is normally only a tiny fraction of the other dust in our atmosphere such as volcanic ash, dust from deserts and sea salt.
  • Extracting the extraterrestrial matter — the tiny meteorites and bits of dust from outer space — involves taking the ancient rock and treating it with acid that eats away the stone and leaves the space stuff.
  • The presence of these special helium isotopes, along with rare metals often found in asteroids, proves that the dust originated from space.