|MadSci Network: Astronomy|
Well, it sort of depends on what you mean by "better off." An asteroid that lands in the ocean will cause tremendous tidal surges that will wipe out most major Coastal cities. An asteroid that strikes on land will cause devastating seismic tremors that will travel to the coast, and THEN set off tremendous tidal surges that will wipe out most major Coastal cities. Additionally, one that strikes on land is much more likely to throw up a massive plume of debris that will cause the "nuclear winter" effect. If you ask me, it's six of one and a half-dozen of the other! As for our planet, it is much, MUCH better to be hit by an asteroid than by a comet. Most asteroids are relatively small -- heck, tiny meteors burn up in our atmosphere all the time. Even the big asteroids are only going to be a few miles across. Comets, on the other hand, are *huge*, and if one hit the earth, well, there probably would be quite a bit more damage.
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