Dust from asteroid blast could shield Earth from global warming
Around half-a-billion years ago, a 150km-wide asteroid broke up between Jupiter and Mars, sending out a vast dust cloud that blocked sunlight and plunged Earth into an ice age.
Now scientists have suggested that a similar man-made event could protect our planet from runaway global warming. The plan would involve towing or pushing an asteroid to a point in space, where gravitational forces even out to provide a static ‘‘parking spot’’, known as a Lagrange spot. The asteroid could then be drilled into, or blown up, to create an ‘‘anchored dust cloud’’ that would shield Earth from the Sun. It might seem extreme, but governments are already looking for ways to deflect or explode asteroids in the event of an incoming space rock. Research by scientists at Lund University in Sweden and Chicago’s Field Museum shows that creating a dust cloud would have the desired goal of significantly cooling the climate, before.
Around 466 million years ago the seas started to ice over and the planet began to freeze. But the cause of this ice age has always proved a mystery. The team discovered huge amounts of asteroid dust buried in the geological record from the time, suggesting temperature falls were because it has happened linked to space debris blocking out sunlight.
Dr Philipp Heck, a curator at the Field Museum, associate professor at the University of Chicago, and one of the paper’s authors, said: ‘‘Our results show for the first time that such dust, at times, has cooled Earth dramatically.’’ He has the most famous surname in American politics but that is no guarantee of victory. Joe Kennedy III, a Massachusetts congressman and scion of the clan that has produced one president, two ambassadors and a US attorneygeneral, hopes to become the family’s fourth US senator.
Kennedy, 38, is to challenge Ed Markey, a Massachusetts senator who has served in Congress for 43 years.
He will formally announce his campaign tomorrow, hoping to attract the youth vote. Political analysts point out, however, that many young voters perceive the dynasty as too centrist and are wary of his privileged background.
A recent Suffolk University/Boston Globe poll of potential Democratic primary voters found that although Markey, 73, was well respected, Kennedy would enter the race as the frontrunner.
About 35 per cent of those polled said that they would back Kennedy, the grandson of Robert Kennedy, the US attorney-general who was assassinated in 1968. Markey was supported by 26 per cent.