Controversial theory suggests Earth formed quickly, increasing likelihood of alien life.

New research from the University of Copenhagen suggests that Earth formed more quickly than previously thought, in just a few million years, by accumulating small millimetre-sized pebbles from the protoplanetary disk. The research also suggests that Earth's water is a result of how it formed from those grains, rather than from incidental collisions with water-rich asteroids and comets. The study focused on the distribution of silicon isotopes in more than 60 different meteorites and planetary bodies, providing a novel perspective on the accretion history of terrestrial planets. The findings could have implications for the search for habitable exoplanets.