The stardust, formed five to seven billion years ago, came from a meteorite that fell to Earth 50 years ago in Australia, they said in a paper published in the journal PNAS. It came down in 1969 ...

Scientists think that by 4.3 billion years ago, Earth may have developed conditions suitable to support life. The oldest known fossils, however, are only 3.7 billion years old. During that 600 million ...