I was talking with a customer support person on the phone yesterday, and somehow the conversation got around to asteroids (don’t ask) and what we can do about an incoming. She was quick to assume there’s nothing we can do about meteorite impacts.
Actually there’s quite a bit we can do about the danger that asteroids pose to planet Earth. I’ve recently been in touch with no less than five organizations that are addressing the problem.
Step one is knowing what’s actually out there. Where are the near-Earth objects, or NEOs, how big are they, what are they made of, and are they likely to hit us in the relatively near future?
These are questions we need to answer to protect outselves, and these are the questions the Planetary Society’s Shoemaker Near-Earth Object Grant Program seeks to answer. Through this program, the Planetary Society gave a grant to the La Sagra Observatory in Spain to upgrade one of its telescopes with a faster camera. That new camera was what alerted planet Earth to 2012 DA14, an Olympic swimming pool size rock that swung by on a close pass on February 15.
Coincidently, that was also the day a much smaller rock vaporized 20-30 miles above Chelyabinsk, Russia. The resulting shockwave blasted out windows and injured hundreds of people. The rock disintegrated because it was of a stony type, which comprises an estimated 96 percent of asteroids. But had it been more metallic, it would have impacted the ground with the force of a nuclear bomb.
We know about less than 3 percent or so of the smaller NEOs, like 2012 DA14, out there. A rock the size of 2012 DA14 that reached the ground could take out Manhattan. A six-mile-diameter space rock wiped out the dinosaurs 65 million years ago. “We live in a cosmic shooting gallery,” says the Planetary Society’s Director of Projects, Bruce Betts.
The B612 Foundation is raising funds to build a space telescope called Sentinel that would orbit the sun well away from the sun and look back at our neighborhood and see what’s there. Said B612 CEO Ed Lu in a statement on February 15:
By the end of its planned lifetime, Sentinel will have discovered well over 90% of the asteroids that could destroy entire regions of Earth on impact (those larger than 350ft in diameter) and more than 50% of the currently unknown DA14-like near-Earth asteroids.
Space startup Planetary Resources, money in hand, is already building a fleet of smaller telescopes that will scan the skies for NEOs from Earth orbit, and startup Deep Space Industries proposes sending fleets of small telescopes on close encounters with NEOs.
As the Planetary Society’s Betts points out, asteroid impacts are the only natural disaster we can prevent. We can deflect incoming rocks with rockets or even paintballs. At the very least, we can evacuate an area of predicted impact. But we can only do those things if we know what’s coming. Planetary defense, starting with detection, should be a priority for all the people of Earth.