Huge space rock slammed into Earth, throwing out debris field 1,200 miles across, researchers say
A UK-based scientist has uncovered evidence of a chunk of space rock hitting Earth at high speed 430,000 years ago, creating a debris plume more than 1,000 miles wide.
The findings highlight the importance of reassessing the threat of medium-sized asteroids with the potential for “destructive” consequences, the researcher said.
Although highly unlikely to hit densely populated parts of Earth, such meteors could cause millions of casualties, it is said.
Matthias van Ginneken, from the University of Kent’s School of Physical Sciences, recovered a number of extra-terrestrial particles on the summit of Walnumfjellet, a mountain in east Antarctica.
The discovery indicated a “low-altitude meteoritic touchdown event”, where a jet of melted and vaporised material from an asteroid at least 100m wide slammed into the surface.
The debris covered a circular area of at least 1,200 miles – an “almost-continental scale distribution”, said Dr van Ginneken.
The research paper, published in the Science Advances journal, said finding evidence of such events remained critical to understanding the history of such impacts and estimating future “hazardous effects of asteroid impacts”.
Dr van Ginneken said while it was highly unlikely that such an event would happen over a densely populated area – with less than 1 per cent of the Earth considered densely populated – its effects could be widespread.
He said: “Severe effects of such an impact can be felt over hundreds of kilometres.
“Therefore, even if such an impact were to occur hundreds of kilometres away from a densely populated area, the amount of devastation would not be negligible and would need to be taken into account.”
He said the study could help improve knowledge of the rate of such impacts in the past and therefore how often they might happen in the future.
“These events are potentially entirely destructive over a large area, corresponding to the area of interaction between the hot jet and the ground,” the research paper states.
“Touchdown events may not threaten human activity, apart from the formation of a large plume and the injection of ice crystals and impact dust in the upper atmosphere, if these occur over Antarctica.
“However, if a touchdown impact event takes place above a densely populated area, this would result in millions of casualties and severe damage over distances of up to hundreds of kilometres.”