Researchers from the Massachusetts Institute of Technology have estimated the lifetime of the solar nebula which is an important stage during which a major part of the solar system’s evolution occurred.
According to this estimate, the gas giants Saturn and Jupiter must have appeared within the first 4 million years of the evolution of the solar system. Moreover, their orbital positions’ gas-driven migration must have been completed by this time.
They analyzed the 4.563 million years old ancient meteorites. The magnetic orientations of these angrites reveal that the solar nebula has been there for some 3 to 4 million years.
Angrites are igneous rocks. Early in the history of the solar system, many of these are believed to have expelled on the surface of asteroids. These then cooled off, preserving their original properties. Specifically, their uranium content helps determine their age precisely. These are therefore viewed upon as exceptional recorders of the early solar system.
"Since the solar nebula lifetime critically affects the final positions of Jupiter and Saturn, it also affects the later formation of the Earth, our home, as well as the formation of other terrestrial planets" says Huapei Wang, the study’s first author.