An ancient meteorite that crash-landed on a British driveway may have solved the mystery of where Earth’s water came from.
The 4.6 billion-year-old space rock, which landed in front of a family home in the English town of Winchcombe in February 2021, contains water that closely resembles the chemical composition of water on Earth. was sprinkled with the life-giving substance.
When the rocky inner planets of the young solar system first merged — clumping from the hot clouds of gas and dust billowing near the sun — they were too close to our star to form oceans. In fact, beyond a certain point called the frost line, no ice could escape evaporation, creating the fry Soil a barren and inhospitable landscape. Scientists think this changed after the Earth cooled, when a barrage of ice formed asteroids from the outer solar system brought frozen water to our planet to melt. Now, a new analysis of the Winchcombe meteorite, published Nov. 16 in the journal Scientific progresshas supported this theory.
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“One of the biggest questions of the scientific community is: How did we get here?” study co-author Luke Daleylecturer in planetary geosciences at the University of Glasgow, said in a statement. “This analysis of the Winchcombe meteorite provides insight into how Earth got water – the source of so much life. Researchers will continue to work on this specimen for years to come and unlock more secrets about the origin of our solar system.”
The space rock, a rare carbon-rich type called carbonaceous chondrite, was collected just a few hours after it was slammed into the ground and thus remains largely uncontaminated, making it “one of the most pristine meteorites available for analysis”; it offers “an enticing glimpse back in time to the original composition of the solar system,” said lead author Ashley King, a research associate at the Natural History Museum in London.
To analyze the minerals and elements in the rock, the researchers polished, heated and bombarded it with X-rays and lasers, revealing that it came from an asteroid orbiting Jupiter and that 11% of the meteorite’s mass is water. existed.
The hydrogen in the asteroid’s water came in two forms: normal hydrogen and the hydrogen isotope known as deuterium, which goes on to form “heavy water.” The scientists found that the ratio of hydrogen to deuterium matched the ratio in water on Earth, strongly implying that the meteorite’s water and our planet’s water shared a point of origin. Amino acids, the building blocks for protein and subsequent life, were also found in the rock.
To expand on this research, scientists can analyze other space rocks that float around the solar system, such as the asteroid Ryugu, which also contains the building blocks of life. A comprehensive examination of the solar system’s space rocks could give scientists even greater insight into which rocks helped seed the early Earth and where they came from.