A Yale-led research team has proposed that large asteroid impacts could have abruptly triggered “Snowball” Earth periods, where the planet was encased in ice, resolving a long-standing debate about these dramatic climate shifts. Their study, using sophisticated climate models, suggests that under certain cold climate conditions, an asteroid strike could tip Earth into a global glaciation state within a decade. Credit: AI-generated image, created and edited by Michael S. Helfenbein
Recent research argues that asteroid impacts may have triggered widespread ice ages in Earth’s ancient history.
A Yale-led research team has picked a side in the “Snowball Earth” debate over the possible cause of planet-wide deep freeze events that occurred in the distant past.
According to a new study, these so-called “Snowball” Earth periods, in which the planet’s surface was covered in ice for thousands or even millions of years, could have been triggered abruptly by large asteroids that slammed into the Earth.
The findings, detailed in the journal Science Advances, may answer a question that has stumped scientists for decades about some of the most dramatic known climate shifts in Earth’s history. In addition to Yale, the study included researchers from the University of Chicago and the University of Vienna.
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NASA launches an asteroid strike simulation this week, but what would happen if a devastating asteroid was coming our way today? RT asks an expert about the tools available, and how long it will be until we’re fully prepared.
While hundreds of small asteroids and meteorites have hit Earth, big objects, like the 55 foot one that exploded over Chelyabinsk, Russia in 2013 only occur around twice a century, and larger (dinosaur-destroying) ones are even less common. However, NASA warns that “given the current incompleteness of the NEO [Near Earth Object] catalogue, an unpredicted impact could occur at any time.”
At the start of 2019, NASA reported there were 19,000 known near-Earth asteroids, with an average of 30 new ones found each week.
Detlef Koschny, co-manager of the Space Situational Awareness (SSA)-NEO Segment of the European Space Agency, told RT that it’s not the large NEOs that we need to worry about, though, but the smaller ones, as scientists are only aware of “one percent or less” of them and “they could still damage a city or region.”
Ideally, scientists hope to have several years’ warning of an approaching NEO of 100 meters or more, but when it comes to smaller ones, it is “more difficult to see them early on,” Koschny explains.
Offensive defense
“Anything larger than 50 meters we’d try to deflect,”Koschny said, pointing to NASA’s 2022 Double Asteroid Redirection Test (DART), which aims to intercept an asteroid’s moonlet when it gets within 11 million kilometers of Earth. The hope is that it can “change the speed of an asteroid via a kinetic impact,” he explained.
Unfortunately, deflection methods require a few years of preparation, and the correct spacecraft would need to be built.
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Olduvai IV: Courage
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