Working from their base in New Mexico, the LINEAR team uses automated one-meter ground based telescopes to probe the skies for so-called near-Earth object (NEO) threats. The discovery of 2011 MD on Wednesday goes to show that we need to get better at identifying potential asteroid threats, investing more money and time into projects like LINEAR. The more time we have, the greater chance there is of us being able to do something about it.
Surprisingly, NEOs are more common than you think with around 8,000 known. This newly discovered interplanetary interloper is thought to measure no more than 20 meters wide, making it no real threat -- but it's a warning all the same.
If 2011 MD did hit us, then it would more than likely break up in the atmosphere and give us an amazing display of fireballs and meteors. As it turns out, it will sail harmlessly by at a butt-clenchingly close distance of only 12,000 kilometers (7,500 miles), 32 times closer than the moon, and closer than geosynchronous satellites.