The Fire Passed By
I'm pretty sure you've all heard about this by now, but those of you who know me personally would be very surprised (dare I say disappointed?) if I didn't cover this one, and several of you sent it to me (thanks, all!) so here goes:
Yow! That was close! One week ago an asteroid whizzed past the earth. Its speed relative to the earth was 23,667 miles an hour (over six and a half miles per second. At its closest it was three times closer than the moon. The thing is, no one saw this one coming. The asteroid was first observed three days after it came by.
The dimensions and mass of the asteroid, designated 2002MN, have not yet been accurately determined, but its diameter has been estimated at between 50 and 120 meters (160 - 390 feet), putting it on a par with the asteroid believed to have caused the 1908 devastaion in Tunguska.
A program is under development to detect and track Near Earth Objects (NEOs), but only those 1km (3,270 feet) or more in diameter. Anyone want to up their budget a little?
If you're interested in NEOs, check out the NEO Information Centre and the Near Earth Object Program. If you want to compare the news stories, Yahoo has a Full Coverage page on Asteroids and Meteors. And definitely check out the University of Bologna's excellent Tunguska Home Page. And try Googling "Tunguska" too; there's a lot of great material and photographs of the aftermath of that incredible event.
All photographs from the Tunguska Home Page, used by permission.