posted on Jul, 13 2008 @ 03:16 AM
Such a world stopping meteor would only have to be about 6 miles wide to wipe off most of the life on the planet. Last year one large meteor was
discovered, by luck, within only a few months of the "close call" it would pass near earth closer then the moon is to the earth.
So the truly painful, but truthful answer is that we might never see such a meteor until a couple of days to a couple of months before such an inpact.
Chances are also good, but far less likely, that we might never see it.
People like to think someone somewhere is aware of all N.E.O (Near Earth Objects), but that person doesn't exist.
Sure we "see" comets, because they reflect and throw off ice and have tails, but such things as meteors don't have to be seen until they are
already falling to our planet.
That's how I understand it anyway.