Researchers have dated the earliest step in the formation of the solar system - when microscopic interstellar dust coalesced into mountain-sized chunks of rock - to 4,568 million years ago, within a range of about 2,080,000 years. The dates established by analyzing a particular type of meteorite, called a carbonaceous chondrite, which represents the oldest material left over from the formation of the solar system. picked by AutumnLotus 11 months ago