The Sun’s planets had a mixed-up birth far more turbulent than previously believed, British scientists reveal today. Dust from a comet was found to be made from material from the inner reaches and the distant edges of the Solar System.
It means there must have been a massive amount of mixing going on within the disks of gas and dust from which the planets formed billions of years ago.
UK astronomers made the discovery by examining minute pieces of dust brought back to Earth from a comet called Wild 2 in January this year.
The particles, captured by a Nasa spaceprobe called Stardust on a seven year, 2.88 million-mile round-trip, were parachuted into the Utah Desert. They gave scientists a unique opportunity to study pristine material unchanged since the earliest days of the Solar System.
Nasa sent some to scientists from The Open University, Imperial College London, the Natural History Museum and the Universities of Kent, Manchester and Glasgow. Their results are published today in the journal Science.
Professor Monica Grady, of The Open University, said: “We are all very excited about what these results mean for our understanding of how the Solar System formed – and what this also means for other planetary systems.
“It seems that the cloud of gas and dust from which our Sun and planets grew was much more active and turbulent than had been appreciated, with mixing between different populations of grains taking place across the whole width of the disk.”
The image is a Nasa artist’s impression of Stardust at Comet Wild 2.