Latest analysis reveals Winchcombe meteorite as ‘seven jigsaws in one’

The fascinating origins of the Winchcombe meteorite, which fell to Earth in the UK in February 2021, have been unveiled through extensive scientific analysis. This meteorite originated from an asteroid that had undergone significant transformations due to water and had been repeatedly broken apart and reassembled.

Found scattered across fields near Winchcombe, this meteorite marked the first such recovery in the UK since 1991. With the assistance of the UK Fireball Alliance and reports from eyewitnesses, scientists pinpointed the area of the meteorite’s fall, swiftly collecting the fragments to minimize contamination. Although some contamination occurred, including exposure to table salt, the fragments retrieved are some of the most pristine ever collected from a meteorite.

Investigative techniques such as transmission electron microscopy, electron backscatter diffraction, and others have revealed the intricate history of the Winchcombe meteorite. Leon Hicks from the University of Leicester highlighted the exceptional level of scrutiny given to these fragments, comparable only to that usually reserved for samples returned directly from space missions.

Recent detailed studies have shown that the meteorite consists of breccia, a type of rock composed of cemented rock chunks. Classified as a CM carbonaceous chondrite—a carbon-rich, stony material—the Winchcombe meteorite is particularly noteworthy because it was formed from eight different kinds of CM chondrite, the most common type of carbonaceous chondrite.

Luke Daly of the University of Glasgow, who led the research, described the meteorite’s complex composition. He likened it to a highly fragmented puzzle, where pieces of the meteorite were as if they were from several other mixed puzzles.

This indicates that the parent asteroid of the Winchcombe meteorite experienced numerous collisions with other asteroids in the early solar system, leading to its repeated disintegration and reformation. Moreover, the meteorite shows signs of chemical alteration by liquid water before it was shattered, with altered and unaltered grains found jumbled together within the breccia.