The implications of an asteroid impact on earth, we know.What is the implications for us, on a moon impact?

Answer 1

there are several important implications
1. If it is large enough it could disrupt the moons orbit

if that large, where does teh moon go, where does the remaining asteroid go? The answer is probably to the earth. (after all, the earth is a very large gravity well from the moon, most things that would come off the moon come to earth)

which would be very bad. Large chunks of the moon would be like a shotgun against the earth. At any massive size, they would just go through the atmosphere, causing massive world wide destruction.

If the moon was that destablized, the you also have the issues dealing with how the tides on the earth would change.

2. if not large enough to destroy the moon/distrupt the moon, you still have all that debris. which means more meteor showers. If large enough, they are capable of doing severe damage (see meteor crater in AZ for a good example)

Answer 2

If the moon impacts with us? Or do you mean if an asteroid impacts with the moon? I´ll answer both just for the fun of it.

First, the moon itself was formed when a huge, mars sized asteroid collided with the protoearth some 4,5 billion years ago. Needless to say that if the moon collided with earth it would be catastrophic for the whole planet.

Second, we can see that the surface of the moon is absolutely riddled with impact craters. The Apollo program took samples of the lunar surface and those were later dated. The biggest craters are so old that they have smaller craters within themselves so big impacts aren´t exactly common. And since the moon is still up there despite some really huge craters we can safely say it won´t fall out of orbit because of an asteroid.
But the moon is hit by small asteroids all the time. On occasion earthbased telescoped actually photograph the small flashes they produce.
We have some samples of lunar rock that fell to earth as meteorites suggesting that a big impact can kick up moonrock with such force that it reaches escape velocity and later fall to earth. So a huge impact on the moon could be dangerous to earth as well. Just as dangerous as any direct asteroid impact. But we also know this: there have been several events of mass extinctions on earth during the history of life. We have been able to date these events and none of them match the age of any of the really big impact craters on the moon.

Answer 3

If there is sufficient force to affect the moon's orbit to any extent, then the tides on Earth will be affected proportionally as well. In addition, if the surface is sufficiently altered by the impact, we may actually be able to observe the new patterns from down here with the naked eye (though I suppose this would be coupled with possibility #1).

Answer 4

Unless it's planet size, we may get a few more meteorites from the moon but that's about it