Material older than the sun found in NASA asteroid mission
Material older than the sun has been found 200 million miles from Earth by a NASA spacecraft.
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"Presolar grains" - the dust of dying stars from billions of years ago - was scooped up from an asteroid and analysed by an international team of scientists.
The study of asteroid Bennu's chemical make-up gives us a "snapshot of the early Solar System' and a "window into it's formation", researchers say, as the samples are cleaner than any meteorite on Earth.
To collect the evidence, NASA undertook one of its most audacious missions ever using spacecraft Osiris Rex.
The probe's robotic arm collected around 120g of material, which was packed into a capsule and returned to Earth in 2023.
Since their arrival, scientists have used chemical analysis to establish Bennu's origins in the cold, dense gas and dust of the early Solar System.
Professor Jessica Barnes, from the University of Arizona, who is one of the study's authors, said: "Our data suggest that Bennu's parent asteroid formed in the outer parts of the solar system, possibly beyond the orbit of Saturn."
There was a plethora of other materials in the sample, including organic matter from the outer Solar System and the interstellar medium - the gas and dust between stars.
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Researchers found high temperature materials too, thought to have formed close to the sun before drifting outwards.
Professor Sara Russell, planetary scientist at the Natural History Museum and another of the study's authors, said: "We're looking at a unique snapshot of the outer Solar System at [the time of] the birth of our sun.
"Some of these grains have survived billions of years of Solar System evolution almost untouched and can tell us more about the environment in which planets were born."
Scientists at the Natural History Museum also found evidence of material from before earth was fully formed, with the samples containing water-driven chemical reactions that began over 4.5 billion years ago.
"Studying Bennu has given us the opportunity to investigate a novel type of space rock, and we are learning new things about it every day," said Professor Russell.
"The lack of reaction with the Earth's atmosphere has given us the opportunity to study the history of the asteroid, and the evolution of the minerals it contains, in incomparable detail."