There is evidence in the well preserved Winchcombe meteorite that water on Earth originated in space.

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A black, soccer-ball-sized chunk of space debris landed to Earth over northern England on the evening of February 28, 2021. The meteorite exploded in a blinding flash of light that lasted for eight seconds before it broke up and hurtled toward the planet. Rob and Cathryn Wilcock's driveway in Winchcombe, a little, historic town, took the brunt of the biggest fragment.

The study of those pieces, published on November 16 in Science Advances, confirms the meteorite's outer solar system origin and reveals the presence of water with Earth-like chemical composition. A longstanding puzzle in science is where Earth received its water. The latest findings lend credence to the theory that water was introduced to the infant Earth by asteroids (SN: 5/6/15).

Members of the Wilcock family weren't the only ones to find shards of the rock that crashed to the ground that evening. On the other hand, they were the pioneers. According to Ashley King, a planetary scientist at London's Natural History Museum, the pieces of the Winchcombe meteorite that were retrieved were only exposed to the earth for a total of 12 hours.

After being followed from orbit to Earth, meteorites have been retrieved before, but never so rapidly (SN: 12/20/12).

As far as meteorites go, King adds, "it's as pure as we're going to get." "We can't actually acquire them much sooner or more pristinely than if it landed in the museum on my desk, or if we sent a spaceship up there," he said.

King and his team tried everything they could think of to analyse the 530 grammes of meteorite they had collected from Winchcombe and other locations, such as a sheep farm in Scotland. They polished it, heated it, and shot it full of electrons, X-rays, and lasers to identify the elements and minerals therein.

Many recordings from doorbell and dashboard cameras were also studied by the researchers, in addition to footage from the UK Fireball Alliance, a network of 16 meteor-watching cameras located across the globe. The movies were used to figure out the meteor's path and origin.

Based on their analysis, the scientists determined that the meteorite is a carbonaceous chondrite, a rare kind of carbon-rich rock. According to the researchers' estimates, it originated from an asteroid in Jupiter's orbit and began its journey toward Earth about 300,000 years ago.

Water is included in hydrated minerals, which chemical analysis has shown make up around 11% of the meteorite's total mass. The ratio of hydrogen to deuterium in the meteorite is comparable to that of Earth's atmosphere, suggesting that some of the hydrogen in that water is the heavier type of hydrogen known as deuterium. According to King, this finding is "strong evidence" that water on Earth originated from water-rich asteroids.

Amino acids and other forms of biological matter were also located by the researchers in the meteorite fragments. According to King, "they are the building blocks for things like DNA." "They don't have life, but they have the beginning point for life locked up in them," she said of the fragments. More research is needed to figure out what triggered the formation of those molecules in the asteroid the meteorite originated from and what mechanisms may have brought comparable organic material to the young Earth.

Planetary scientist Meenakshi Wadhwa of Arizona State University in Tempe, who was not involved in the work, says, "It's always intriguing to have access to material that might give a fresh window into an early time and location in our solar system."

In the future, she would want to see scientists compare the Winchcombe meteorite to the asteroid samples of Ryugu and Bennu that were brought back to Earth by spacecraft (SN: 1/15/19). These two asteroids are far closer to Earth than the main asteroid belt, from where the Winchcombe meteorite originated. By analysing the similarities and differences between these three samples, we may better understand the composition of the early solar system and its development into the system we observe today.