New evidence has emerged suggesting that the building blocks of life were delivered to the primordial Earth from space by meteorites, a finding that could help scientists hunt for alien life.
These meteorites would have been the fractured remains of early "unmelted asteroids," a type of planetesimal. Planetesimals are small rocky bodies that served as the main building blocks of the solar system's rocky planets, including Earth. They were formed around 4.6 billion years ago in the disk of dust and gas around the infant sun as particles around our young star began to stick together, accreting more mass and making progressively larger bodies.
