Meteorite’s water gives clue to origin of life on Earth
Analysis of chunk of rock that fell on a Gloucester driveway reveals close link to the world’s oceans
EXTRA-TERRESTRIAL water has been found in a British meteorite for the first time – and it closely resembles Earth’s oceans, scientists have confirmed.
The Winchcombe meteorite landed on a driveway in Gloucestershire in February last year, and was found so soon after impact that researchers believe it is one of the most pristine ever discovered.
The chunk of rock came from the asteroid belt between Jupiter and Mars, and, crucially, contains significant amounts of water that match closely to that on Earth, as well as amino acids – important building blocks of life.
Many scientists believe life began on Earth after it was bombarded by asteroids or comets containing life-giving ingredients. But most that have been studied contain water of a different composition to that found on Earth.
The new research shows the Winchcombe meteorite is comprised of water that is very close to that in our oceans, suggesting that life was seeded on our planet by rocks travelling through space.
Dr Ashley King, of the Planetary Materials Group at the Natural History Museum and the UK Fireball Alliance told delegates at the British Science Festival in Leicester: “What’s really exciting for us for us is that Winchcombe meteorite was collected about 12 hours after landing, so the water that’s in the rock hasn’t been contaminated with the water that we have in our atmosphere. So it’s basically really fresh.
“We can be really confident when we measure the water that it is extra-terrestrial water. The composition of that water is very very similar to the composition of the water in the Earth’s oceans.
“So it’s a really good piece of evidence that asteroids and bodies like Winchcombe were delivering really important contributions to the Earth’s oceans.
“It’s also got two per cent carbon and a significant fraction of that is organic materials, such as amino acids. If you want to start making DNA and stuff, you need amino acids, so all of these starting materials are locked up in the Winchcombe meteorite.”
Although other meteorites have been found containing water that resembles water on Earth, scientists had never been sure whether they had picked it up while lying around after landing.
The Winchcombe meteorite was part of an asteroid that formed around 4.6 billion years ago from the leftover planet-building material of the early Solar System. But after a chunk was knocked off, it took around 300,000 years to reach Earth, scientists believe. It contains around 12 per cent water, which is locked up in minerals in a kind of mud. It was the first to be found in Britain since 1991.
Meanwhile, the meteor that was spotted earlier this week over the skies of Scotland and Northern Ireland is believed to have crashed in the Atlantic, near the Hebrides.