More asteroids to Buzz the Earth this week

A newly-discovered asteroid designated 2009 FH will fly past Earth tonight only 80,000 km (0.00057 AU) away. It was discovered by the NASA's US based Near Earth Object Observation Program, known as Spaceguard. 80,000 km is a little more than twice the height of a geosynchronous communications satellite.  Experienced amateur astronomers in North America should be able to photograph the 20-metre-wide space rock racing through the constellation Gemini after sunset tonight. For Southern Observers, it will be very low on the horizon and only visible for about an hour after sunset.  It should be about as bright as a 14th magnitude star. You can get an ephemeris and updates at spaceweather.com.

Interestingly, this new object comes only two weeks after a larger (50 metre wide) asteroid 2009 DD45 was spotted passing the Earth at a similar distance on March 2nd. So it begs the question, why are we seeing so many asteroids lately?
 On March 2nd, 2009 DD45 passed by only 72,000 km away.  Measuring some tens of meters in diameter, 2009 DD45 and 2009 FH are approximately Tunguska-class objects, meaning they pose no global threat but could cause local damage if they actually hit Earth.  In years past, asteroids of this size often passed unnoticed, but recent improvements in asteroid surveys have resulted in growing numbers of space rocks caught in the act of near-Earth flybys.

"This asteroid flyby will be a good viewing opportunity for both professional and amateur astronomers," said Don Yeomans from the Near-Earth Object Office at NASA's Jet Propulsion Laboratory in Pasadena, California. "The asteroid poses no risk of impact to Earth now or for the foreseeable future."

There will be another recently discovered rather larger piece of rock designated 2009 DO111 which will pass by around 1 and a quarter lunar distances away. This one which is between 70 and 170 meters in size was first spotted by the Steward Observatory at Kitt Peak USA. It won't be visible down under though.

Although it might seem there are a lot more asteroids than before, this isn't the case, the technology is just getting better at finding them.