Comment Re:Surprising number (Score 1) 256
You keep talking about a large asteroid that is definitely on a collision course with earth. This is an error. There have been large asteroids that been on collision courses before. There may be more, but it is not certain. Because it is not 100% probable that an unknown large asteroid is currently on a collision course with earth none of your argument is valid, and your arguments about increasing probabilities are incorrect.
Your argument would be valid (but pointless) if you said: "if there is at least one more asteroid on a collision course with earth then the probabillty of impact on a particular day increases with each day it does not strike". Of all the asteroids that strike earth of a given size, one of them is the last.