Asteroid to pass Earth closer than the Moon today

There are no known immediate threats to Earth when it comes to an asteroid impact, but our planet seems to be receiving a number of flybys lately. In February of this year, the Earth recorded its closest near miss when asteroid 2011 CQ1 avoided an impact with the planet by only 3,405 miles. Now, another close shave today is expected to come within 7,500 miles, which will put the asteroid closer to the Earth than the Moon (32x closer in fact) and in the same area as some communications and television satellites. What is a bit scary about this latest asteroid is that it was only discovered late last week.

The asteroid has been designated 2011 MD and was discovered by a pair of robotic telescopes which are a part of MIT’s Lincoln Near Earth Asteroid Research (LINEAR). It’s still unclear, but 2011 MD is thought to be between 8 and 18 meters in diameter, or roughly as big as a large house.

LINEAR, funded by the United States Air Force and NASA, is applying technology originally used to track Earth orbiting satellites toward the goal of tracking and cataloging near-Earth asteroids. When a discovery is verified by LINEAR it is then sent on to the Minor Planet Center (MPC) which applies a designation to any new discovery. What is interesting about 2011 MD is that it may not be an asteroid at all. Astronomers are looking into the possibility that what we may believe is an asteroid is actually a discarded rocket booster from a previously launched planetary probe due to its Earth-like orbit.

Unfortunately, most people won’t be able to see 2011 MD when it passes by. The time of the event will be 1pm EST meaning daylight hours for most of the U.S. and Europe. South Africe and Antartica will be able to see it pass, while New Zealand and Australia should be able to see part of the approach.

2011 MD’s passing won’t mark the end of the excitement around near-Earth asteroids this year. An asteroid designated 2005 YU5 is 400-meters wide and expected to pass within the orbit of the Moon on November 8th. At least, that’s when the next known near-Earth asteroid is expected. There is always the possibility that LINEAR could detect another near-Earth asteroid before then and like 2011 MD we may not have a lot of lead time that it is coming.

Read more at Skymania and Sky & Telescope