K.I.L.E.R said:
This scares me, this is why I believe something should be done about this.
Something be done ... something like what?
Meterorites and comets are really nothing to worry about, they're kids stuff, there's no way they threaten the end of the world. Earth has been hit by them on many previous occasions and survived, suffering little more than a major extinction event wiping out ~85% of life on Earth. Hardly the end of the world!
What you really want to be worried about is a collision with a Mars-sized object, eg. the
Moon-forming impact, which really did threaten the structural integrity of the planet. Quite how we'd divert a planet-sized body on collision course with Earth is pretty much a matter of science-fiction, and will be for centuries to come. But the good news is that that's already happened, and there's no evidence for rampant Mars-sized bodies on Earth-crossing orbits.
But look on the bright side, without the Moon-forming impact we wouldn't have such a large Moon. The influence of the Moon which has been suggested as a contributing factor to the overall stability of the Earth's climate, stability which has allowed life to flourish. Even the mass-extinctions caused by comets & meteors are good news for some ... the wiping out of the dinosaurs allowed mammals to take their place, including humans. No meteor strike = no Kruno.
Or... perhaps you should worry about more practical matters. It makes far more sense to worry about dangers you can actually do something about. Compare, for example, the number of people hurt by meteorites in the past decade with the number who have come second in a dispute with an ironing board.
Instant giga-death from space is either going to come, or it's not. If it does there's nothing we can do to stop it, so there's no point worrying about it. If it doesn't, there's no point worrying about it. Much better to get on enjoying what little of our lives we have left really.