I've just had a meteor hit my greenhouse. The greenhouse was not destroyed, but everything inside was. After I had replaced all the objects, I still had the dirty surroundings moodlet. I replaced all the windows and doors, still had the dirty surroundings. Replacing the roof fixed it. Personally, I don't think meteor showers add anything to the game, but they sure can ruin it quickly if your sim gets killed, or, to a lesser extent, you can't locate the cause of the dirty surroundings which follows.