[dirtboy]

Just know planet-wide destruction could be under a week away and we could have no idea. Neato.

Uh, a bus-sized asteroid ain't gonna destroy the Earth. But don't let the internet moron community stop preaching the doom and gloom.

[Williams]

No but I recall a prominent astronomer say the real thing could slip into our atmosphere undetected with little or no advance warning.

[SunkenCiv]

Yeah, I enjoyed the hyperbole. A 25 foot wide asteroid would *probably* fragment into smaller pieces after burning off a bit, due to the stress caused by its rapid passage through the atmosphere. A similarly-sized bolide apparently did just that — breaking up into small pieces before impact — back in 1972. There was apparently an audible roar as it came in.

http://www.youtube.com/watch?v=SwWc_eCkSyw

http://www.youtube.com/watch?v=vBu-yUzWXqg

http://www.youtube.com/watch?v=wIv7wL9nWMQ

[AnotherUnixGeek]

Uh, a bus-sized asteroid ain't gonna destroy the Earth.

No, but it could have devastated a major city. The fact that an object of that size could get that close before being detected is worrying. Programs like the CalTech JPL Near Earth Object Program are a great start, but obviously there's a long way to go. As for actually preventing asteroid impacts, that's a long way from even getting off to a start.