Every time there have been reports about killer asteroids and such, and the need to improve our tracking to increase the warning time if something big was going to hit, I’ve wondered what RIGHT NOW would be the minimum warning time. The ones they find are generally “10% chance of collision in 200 years” and such. BUt with current technology, if something was taking dead aim, right at us… would we for sure catch it a few days in advance? A few weeks? Hours?
Welp, the answer is that if it comes from certain directions, we’ll know when it hits and not before. Goody.
Closest asteroid yet flies past Earth (New Scientist)
An asteroid about the size of a small house passed just 88,000 kilometres from the Earth by on Saturday 27 September – the closest approach of a natural object ever recorded. […] The asteroid, designated 2003 SQ222, came from inside the Earth’s orbit and so was only spotted after it had whizzed by. The first sighting was on Sunday 28 by the Lowell Observatory Near-Earth Object Search program in Arizona, US.
OK. So it was a pretty small one that would have mainly made a pretty neat lightshow and not actually damaged all that much, but still… we didn’t know about it until it had already passed. I do still wonder if this is also the case for larger ones, like the 80m one that missed us in 2002 that could have wiped out a city if it hit and crashed in the wrong place. I’m guessing yup, while odds are increadibly low of it actually happening in any give time period (say our lives), it could still happen with no warning at all.