We usually think of asteroids as things we'd like to keep away from the Earth, but people keep coming up with ways we can use them. First there was that whole mining operation plan, and now researchers are theorizing that we could use asteroids to slow down or even stop climate change on Earth. But how?
Scientists have a lot of ideas for how to affect climate change. Some advocate massive geoengineering projects to directly alter the Earth's oceans or atmosphere, but others take a more global approach by suggesting we solve the problem from space and find some way to reduce the amount of solar radiation hitting the planet. One idea is to reflect sunlight away using giant mirrors in space, but that would be incredibly expensive and difficult to pull off, not to mention the boatload of bad luck you'd get if those things broke. So instead, a group of researchers is now proposing the creation of a large cloud of dust in space that would reduce solar radiation by 1.7 percent.
"A 1.7 percent reduction is very small and will hardly be noticeable on Earth," said researcher Russell Bewick, a space scientist at the University of Strathclyde in Scotland. "People sometimes get the idea of giant screens blocking the entire sun. This is not the case ... as [the device] is constantly between the sun and the Earth, it acts merely as a very light shade or filter."
So, how do you create that shade? You could just generate some dust and leave it there, but it would eventually disperse, so it would be easier to come up with some kind of constant source of matter that could anchor the dust cloud in one place. The solution? An asteroid.
The idea is to outfit a near-Earth asteroid with an electromagnetic device called a "mass driver," then use the mass driver to propel it to Lagrangian point L1, a point in space between the Earth and the sun where the asteroid would essentially be held in place by opposing gravitational pulls. The mass driver could then be used to both spew dust from the surface of the asteroid and hold the resulting cloud in place, creating a shade.
If we pulled this off using the largest near-Earth asteroid, the 286 million-billion-pound (no, that's not a typo) 1036 Ganymed, it could generate a dust cloud 1,600 miles wide that would reduce solar radiation by 6.58 percent.
But of course, things could also go horribly wrong.
"A very large asteroid is a potential threat to Earth, and therefore great care and testing would be required in the implementation of this scenario," Bewick said. "Due to this, the political challenges would probably match the scale of the engineering challenge. Even for the capture of much smaller asteroids, there will likely be reservations from all areas of society, though the risks would be much less."
Add to that the knowledge that we can't really test this kind of thing on a large scale before we implement it, and it sounds almost impossible. And even if it did happen, Bewick emphasized that the electromagnetic asteroid cloud solution would only be a temporary fix.
"I would like to make it clear that I would never suggest geoengineering in place of reducing our carbon emissions. We can buy time to find a lasting solution to combat Earth's climate change. The dust cloud is not a permanent cure, but it could offset the effects of climate change for a given time to allow slow-acting measures like carbon capture to take effect."
What do you think? Is this a viable solution or a crazy scheme?
(Via Huffington Post)