Astronomers have found that the recently discovered Earth threatening asteroid 2007 RR9 is in fact the long lost object 6344 P-L observed nearly half a century ago.

 

"The object was long recognized to be dangerous, but we didn't know where it was. Now it is no longer just out there," said Jenniskens.

 

http://in.news.yahoo.com/071005/139/6ll7d.html

 

Heh, did we forget about it too, I thought one missing PHA would create a lot of buzz...

I feel unconfortable with the fact that we are losing track of potentially lethal asteriods. We need a better monitoring system, or at least work on our current one until it can track all the near Earth asteroids.

I don't think we are losing track of asteroids nowadays, we lost this single one ~47 years ago.

 

Don't know if we even had monitoring systems back then, but the LINEAR is pretty impressive.

 

The LIncoln Near-Earth Asteroid Research (LINEAR) project is a cooperative project between the United States Air Force, NASA, and MIT's Lincoln Laboratory for the systematic discovery and tracking of near-Earth asteroids. LINEAR is responsible for the majority of asteroid detections since 1998. As of 21 October 2004, LINEAR had detected 211,849 new objects of which at least 1622 were near earth asteroids and 142 were comets. All of LINEAR's discoveries were made using robotic telescopes.

http://en.wikipedia.org/wiki/Lincoln_Near-Earth_Asteroid_Research