Earth’s atmosphere adds a quick pinch of salt to meteorties, scientists find

GlOUCESTERSHIRE: New analysis of the Winchcombe meteorite has revealed just how quickly space rocks which fall to Earth can be contaminated by our atmosphere. 

The meteorite, which landed in Gloucestershire in February last year, was the first to be recovered on UK soil in nearly 30 years. 

Fragments were recovered from a domestic driveway hours after it entered the Earth’s atmosphere. More pieces were found in a sheep field six days after that.

The results show that despite the rapid recovery of the meteorites, the fragments quickly developed several ‘terrestrial phases’, salts and minerals which developed from the interaction of their surfaces with the damp environment in which they landed.

The findings could inform future efforts to protect new meteorites after they are found. They could also help geological missions to asteroids and other planets keep their samples free of terrestrial contaminants once they return to Earth. 

The paper’s lead author is Laura Jenkins, a PhD student at the University of Glasgow’s School of Geographical & Earth Sciences. 

She said: “Analysis of meteorites can provide insights into  the asteroids they come from and how they have formed. Winchcombe and other meteorites like it contain extra-terrestrial water and organics, and the asteroids they come with may be responsible for delivering water to Earth, giving it enough water to form its distinctive oceans. 

“However, when a meteorite is exposed to terrestrial contaminants, especially moisture and oxygen, it undergoes changes, affecting the information it provides.”