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: http://www.badastronomy.com/bad/movies/mib2_review.html
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Review: Men in Black 2
I'm not sure what went wrong between the first movie, which was wonderful, and this one, which was passable, but nothing special. Somehow, the charm and irreverence of the first movie was gone this time around. Be that as it may, this one had fewer real references to astronomy, but what it did, it got wrong. Oh well. Let's get this over with.
Bad:
Good: But that's no fun. Well, it might be fun, but really, how much energy does it take to blow up a planet? I did this calculation once before, to show that a comet impact could not destroy a planet. To blow up a planet, you have to overcome the gravity of the planet for each piece. Let's put it another way: Imagine taking a rock and throwing it up so hard it escapes from the planet entirely. For the Earth, that means you have to give it a pretty big velocity, about 11 kilometers per second. It takes a lot of energy to do that, the amount of which depends on the mass of the rock and the amount of gravity you are fighting. Now take another rock, and do it again. And again. And againandagainandagain. Repeat for a gazillion times. If you do it enough times, the planet is gone. You've destroyed it. Congratulations! It's possible to calculate that total energy you expended. It's called the gravitational binding energy, and is basically the amount of energy locked up in the planet's gravity. I'll spare you the math (but you can find it here if you'd like), but for the Earth that energy is roughly 1039 ergs. An erg is a tiny unit of energy, but 1,000,000,000,000,000,000,000,000,000,000,000,000,000 is a lot of them! For comparison, the Sun puts out about 4 x 1033 ergs every second, so the amount of energy needed to vaporize the Earth is about the total amount of energy the Sun emits in 3 days! That's a whole lot of energy. I doubt a single ship could generate that much. But who knows? They're aliens!
Bad:
Good: The ozone hole is caused by chemicals like chlorofluorocarbons, which break down the ozone molecule. Both global warming and the destruction of the ozone layer can be traced to what amounts to mankind's pollution, but they are very different beasts. And to prevent the flood of email from people who want to berate me politically for saying we are causing global warming, I will say:
Bad:
Good: As an example, when the Palomar Observatory was built, the designers decided that about a hundred miles away from Los Angeles would be a good site. Now look: since that time, the sky has been ruined by the huge city, and the observatory (which housed what was the largest telescope on the planet for decades) now has to struggle to do scientific research. The problem got bad enough that an organization was founded to help educate people about it. The International Dark Sky Association promotes smarter lighting systems, which are not only safer for people (they tend not create deep dark shadows where someone can hide) but also are more efficient, meaning they cost less in the long run. A whole generation of kids is growing up not knowing what a truly dark sky is really about, and that's too bad. It would be a shame if the easiest way for them to see one is when it is faked in a movie scene.
ConclusionThat's really it. The movie is only 88 minutes long, not really enough time to make too many mistakes. This review is more of a chance for me to rant a bit, so thanks for listening. I would say that this movie is more of a renter than something to blow good money on at the theater. That's really unfortunate, because the original is a really good flick. I assume they'll make a third one of these. I hope they come up with a script that has personality closer to the first rather than the second movie. |
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