It could potentially save the Earth

Apr 17, 2009 10:09 GMT  ·  By

North Carolina State University (NCSU) doctoral candidate in aerospace engineering David French is the person the entire planet will be indebted to in the event that an asteroid makes its way on a collision course with Earth. The expert has devised a new way of ensuring that asteroids that could destroy all life on our planet never manage to hit us. His technique involves attaching ballast and a long tether to the incoming celestial bodies, basically changing their center of mass, and therefore their trajectories.

“You change the object's center of mass, effectively changing the object's orbit and allowing it to pass by the Earth, rather than impacting it,” French explained. According to NASA's Near Earth Object Program (NEOP), more than 1,000 objects in the sky have already been labeled as “potentially dangerous” to human civilization, and the number is growing with each passing day, as new asteroids are discovered everywhere around us.

“While none of these objects is currently projected to hit Earth in the near future, slight changes in the orbits of these bodies, which could be caused by the gravitational pull of other objects, push from the solar wind, or some other effect could cause an intersection,” the expert added.

Together with Andre Mazzoleni, who is the NC State Associate Professor of Mechanical and Aerospace Engineering, French endeavored to find out if attaching an asteroid-tether-ballast system to an incoming object could successfully alter its center of gravity to such an extent that it would significantly change its course and trajectory.

“It's hard to imagine the scale of both the problem and the potential solutions. The Earth has been hit by objects from space many times before, so we know how bad the effects could be. For example, about 65 million years ago, a very large asteroid is thought to have hit the Earth in the southern Gulf of Mexico, wiping out the dinosaurs, and, in 1907, a very small airburst of a comet over Siberia flattened a forest over an area equal in size to New York City. The scale of our solution is similarly hard to imagine,” French said.

“Using a tether somewhere between 1,000 kilometers (roughly the distance from Raleigh to Miami) to 100,000 kilometers (you could wrap this around the Earth two and a half times) to divert an asteroid sounds extreme. But compare it to other schemes – they are all pretty far out. Other schemes include: a call for painting the asteroids in order to alter how light may influence their orbit; a plan that would guide a second asteroid into the threatening one; and of course, there are nukes,” he shared.

“Nuclear weapons are an intriguing possibility, but have considerable political and technical obstacles. Would the rest of the world trust us to nuke an asteroid? Would we trust anyone else? And would the asteroid break into multiple asteroids, giving us more problems to solve?” French concluded.