Space material fell on the town of Winchcombe, in southeastern England, last year, and contained water almost perfectly like the water on Earth
This reinforces the idea that rocks from space may have brought important chemical components, including water, to our planet early in its history, billions of years ago.
This meteorite is considered the most important one ever recovered in the UK.
Scientists, who have just published the first detailed analysis, say the object has yielded fascinating information.
Over 500g of dark debris was collected from residential gardens, sidewalks and fields after a giant fireball lit up the Winchcombe night sky.
The fragmented remains were carefully catalogued at London's Natural History Museum and then loaned to teams across Europe for investigation.
Water accounted for up to 11% of the meteorite's weight - and contained a very similar proportion of hydrogen atoms to that of water on Earth.
Some scientists say that the Earth when it was young was so hot that it would have expelled much of its volatile contents, including water.
The fact that the Earth has so much water today - 70% of its surface is covered by oceans - suggests that there must have been a later addition.
Some claim that this may come from a bombardment of icy comets - but their chemical composition doesn't match up that much.
But carbonaceous chondrites - meteorites like Winchcombe's - certainly do match.
The fact that it was recovered less than 12 hours after the fall means that it absorbed very little terrestrial water, or even any contaminants.
"All the other meteorites were compromised in some way by the terrestrial environment," Ashley King, lead coauthor of the study, from London's Natural History Museum.
"But the one from Winchcombe is different because of how quickly it was collected."
"That means that when we analyze (the meteorite), we know that the composition we're seeing takes us back to the composition at the beginning of the Solar System, 4.6 billion years ago".
"Other than fetching rock samples from an asteroid with a spacecraft, we couldn't have a more untouched specimen".
PRECISE TRAJECTORY
Scientists who examined the meteorite's carbon- and nitrogen-containing organic compounds, including its amino acids, got an equally clear picture.
It's the kind of chemistry that could have been raw material for biology to begin with in the early days of Earth.
The new analysis also confirms the origin of the meteorite.
The video images of the fireball allowed the researchers to work out a very precise trajectory.
A back calculation indicates that the meteorite came from the outer part of the asteroid belt between Mars and Jupiter.
Further research reveals that it detached from the top of a larger asteroid possibly due to a collision.
It then took only 200,000 to 300,000 years to reach Earth, as revealed by the number of specific atoms, such as neon, created in the matter of the meteorite by constant irradiation of high-speed space particles, or cosmic rays.
"0.2 to 0.3 million years sounds like a long time - but from a geological point of view, it's really very fast," explains Helena Bates of London's Natural History Museum.
"Carbonaceous chondrites need to get here quickly or they don't survive, because they're so brittle, so fragile that they just disintegrate".
MORE SECRETS
The scientists' first analysis, published in this week's issue of Science Advances, is just an overview of the properties of the Winchcombe meteorite.
A dozen more papers on more specific topics should be published soon in an issue of the journal Meteoritics & Planetary Science.
And it shouldn't stop there.
"Researchers will continue to study this specimen for years to come, unlocking more secrets about the origins of our Solar System", said study co-author Luke Daly of the University of Glasgow in Scotland.
https://www1.folha.uol.com.br/ciencia/2022/11/o-meteorito-que-reforca-tese-de-que-agua-da-terra-veio-do-espaco.shtml
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