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: http://www.badastronomy.com/bad/tv/doomsday.html
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The (Dysfunctional) Family Channel's version of Chicken LittleIf you believe your TV (and who doesn't), then you know there are billions of asteroids roaming around the solar system, all waiting for their chance to impact the Earth and wipe out human civilization. If another movie like the Family Channel's "Doomsday Rock" is produced, then I think the asteroids will be doing us a favor.For some reason, in recent months there have been more TV shows aired about asteroids than there are actual asteroids. When they stick to documentaries, the shows have in general been pretty good. However, NBC decided to make a fictional account of an asteroid strike in their awful, awful made-for-TV movie "Asteroid", which I cannot say enough bad things about. However, after watching "Doomsday Rock", I can honestly say it makes "Asteroid" look like a work of genius. Before I get truly started here, please take a look at my web page where I review NBC's stab at astronomy. Many of the points I make here will be similar to (if not exactly equal to) points made there. When I refer to something I said on that page, I'll simply link to it and let you find the reference. First, a quickie plot review: Connie Sellecca plays an astronomer whose father, Dr. Sorensen (played by William Devane), predicts that (stop me if you've heard this before) an asteroid will hit the Earth, causing fires, making acid rain, wiping out civilization, etc. etc. No one believes him, so he of course takes over a nuclear missile silo in Colorado, from which he can launch a couple of nuclear ICBM's at the incoming asteroid and blow it up. The reason people don't believe him is because all the orbital calculations show the asteroid will miss the Earth. The reason he believes it is because of an Australian aboriginal legend that the Earth will end via a "Demon Rock" near the end of the 20th century. Right. Still following me? So at the last moment he is proved to be correct, nuclear missiles are launched, the asteroid is vaporized seconds before impact, and everyone is happy. Everyone but me that is. Now obviously from my description this movie was not really meant to be completely accurate, and they, like the movie "Asteroid", were willing to sacrifice a bit of scientific credibility for the plot. However, also like "Asteroid", every bit of astronomy they put in was wrong, and the plot was even worse than "Asteroid"'s. I noticed they had a scientific advisor for the movie, but once again, for reasons known only to The Powers That Be at the Family Channel, they obviously completely ignored his advice. So without further ado, let's list out what Bad Astronomy the movie promulgated (in the following list, I will refer to "Doomsday Rock" as "DR" for simplicity):
Bad: In an early scene of "DR", Connie Sellecca is lecturing students about astronomy, and one of them asks her the difference between a black hole and a neutron star. She says (paraphrased) "Take Cygnus X-1. It produces gamma rays. Neutron stars have a magnetic field so intense that gamma rays cannot escape. That's how we know it was a black hole."
Good:
The reason we see gamma rays (and all other forms of electromagnetic radiation) from black holes at all is because the huge gravity of the black hole only stops radiation very close in. The gravity effects reach out a long way, however, and can affect matter around it, drawing it in. As the matter spirals into the black hole, local effects heat the matter up to incredible temperatures, which in turn makes it emit all sorts of radiation. That's why we think Cygnus X-1 is a black hole. In that scene, they try to establish Sellecca as a brilliant astronomer, but really they accomplished exactly the opposite. Another point: when being grilled by the FBI, an agent comments that she is overqualified to teach high school astronomy. I personally found that a bit insulting. Teaching is one of the most important aspects of astronomy. You may not need a PhD to teach high school, but they implied that it was beneath her. I believe that teaching astronomy is pretty noble, and anyone who tries to teach it to high school students deserves a medal, not derision.
Bad: Dr. Sorensen, after taking over the nuclear missile silo, demands (from the Defense Secretary!) the immediate use of Hubble Space Telescope (HST). He says he has the coordinates and it will only take a few minutes to point it. After his demand is met, he immediately gets live video feed of the asteroid from HST, showing the spinning asteroid clearly.
Good:
Second, HST cannot take video. You can take a series of observations if you'd like, and then turn them into a movie, but it takes days, weeks or even months to do so. Third, and related to the second point, it takes a long time to analyze HST data. Even a team of people can take months just to properly get the data in a form where it can be analyzed, and the analysis can take years. Having a live video feed is ridiculous. Fourth, since impact was hours away, the asteroid would be moving far too quickly for HST to track it. HST is able to track moving objects like planets, comets, asteroids, etc., but only up to a point. Something moving 50,000 miles per hour and less than a day away would be moving too quickly to track, unless it was headed straight for us. However, in the movie several times, it is stated that the asteroid will miss us by "half a million miles". Therefore it was not headed straight for us and HST couldn't track it. Fifth (fifth! in one scene!), why use HST at all? Hubble is a great telescope in many ways, but it is not a particularly large one. A bigger, ground-based 'scope would be able to image the asteroid much faster, and they wouldn't have to wait two weeks just to get the observation scheduled! But of course everyone has heard of Hubble, so having him demand it was very dramatic. It was also Bad. Incidentally, later in the movie Sellecca uses a dinky little 'scope and gets as good data as Sorensen did from HST. Go figure.
Bad: In one scene, Sellecca needs to check the asteroid's orbit herself. She flies to the Space Scan Observatory in Virginia to use a telescope there. The telescope is located in a lit room, surrounded by computer monitors.
Good:
Bad: Later, Sellecca goes to Puerto Rico to use the Arecibo radio telescope. Calling it the "best radio telescope in the world", she uses it to get more confirmation of the asteroid's orbit.
Good:
Another problem is with the way Arecibo works. It is built into ground, instead of having a free-standing dish. This allows for more rigid design, which is a convenient way to make it bigger. However, this design limits the amount of sky the 'scope can see. Basically (the last I heard), it was limited to about +/- 30 degrees from straight up. The asteroid would have to conveniently be coming in from that area, and be up in the sky at that particular time. Yet even more silliness on the writers' part. But then, why use a radio telescope at all? An optical telescope would do a better job and be easier to use. Once again, the writers just wanted a "gee-whiz" scene, despite any footing in reality.
Bad: Let's look at the asteroid itself: it's about 10 by 5 by 3 kilometers in size, made almost entirely of iron and moving in at 50,000 miles per hour. It is said that the impact will be like the simultaneous detonation of 30 atomic bombs. Sellecca likens it to "shooting a cantaloupe from 10 yards with a 44 Magnum."
Good:
(Note added March 9, 2003: Well, how silly. I made two mistakes in this page originally. I said the mass was 10 trillion tons, when it's really one trillion. I also said the kinetic energy is 5 x 1030 ergs, when it's really 2.5 x 1030 ergs. I corrected these numbers, and state the errors here to keep me honest! My thanks to Bad Reader John Owens for pointing these out to me.) Moving at 50,000 mph (or about 2 million centimeters per second) means it has a kinetic energy of 2.5 x 1030 ergs. An erg is teensy unit of energy: one megaton is about 4 x 1022 ergs. But wait! We have a lot of ergs in that asteroid. The kinetic energy of the asteroid is about one hundred million megatons! Considering that a large hydrogen bomb is only a few tens of megatons (the largest ever exploded was less than 60), we see that the writers woefully underestimated the energy of the asteroid. Now, not all of the kinetic energy of the asteroid goes into the impact, but if even 1% of it does, we still have something that dwarfs the nuclear capability of every nation on Earth combined. However, it is nowhere near enough to actually shatter the Earth. Actually, it's only enough to leave a big crater, but even that crater would only be a few kilometers deep. Using gravitational arguments, it can be shown that it would take about 1040 ergs to shatter the Earth. So that asteroid has less than 1 ten-billionth the energy to do that. The movie certainly played fast and loose with their numbers!
Bad: At 50,000 mph, the asteroid is said to be 19 minutes from impact. The next graphic shows the asteroid over the Moon's surface, complete with shadow.
Good:
Bad: Shortly before impact, the asteroid collides with a comet, which changes the course of the asteroid, aiming it towards Earth.
Good:
One more point, though: this comet was predicted to split in two, one piece of which would collide with the asteroid. Predicted, of course, by the Australian aborigines. However, after the fact, no one seems to care that some primitive tribe was actually capable of predicting the future, which is in direct contradiction with just about every tenet of physics known today. Incidentally, since they blew the asteroid up, the prediction was wrong. Sellecca said the timeline of the future written by the tribe ended at the 20th century. I guess we still have three years to get hit by another asteroid. Now that I think of it, that would have been a semi-cool ending: they all realize the prophecy didn't come true this time, so there must be another asteroid out there...
Bad: Two nuclear missiles blow up the asteroid.
Good:
I have lots of minor nitpicks as well: They launch a missile early on as a bluff. The altimeter shows it rising at about 100 feet a second at best. That's about 100 kilometers an hour, or about as fast as a car on the highway. At that speed, it would take ten minutes just to get out of the lower atmosphere! It would have taken hours to get into orbit. They say the Pentagon is in Washington DC. It isn't. It's in Arlington, Virginia. An astronomer mentioned Halley's comet, but pronounced it "Hay-lee". Every astronomer I know pronounces it "Hal-lee", since Halley was British. Also, comets are referred to as "Comet such and such", not "such and such Comet". Over and over again, Sellecca says that the comet will "split". The astronomy term for that is "calving". Why didn't she ever use it, even when talking to another astronomer? The Russians launch a missile to help our missile destroy the asteroid. However, the asteroid was so close by then that the Russian missile would never have had time to get all the way over to it, let alone at the same time as the U.S. missile. During this whole thing, the President never gets involved. The Defense Secretary calls all the shots, including one where she orders an atomic bomb raid on a missile silo inside U.S. boundary. Where was the President? Yegads. A military advisor to the President pronounced "NASA" as "Nassau". I'd think someone of his authority would know the difference between a multi-billion dollar agency and the capital city of the Commonweath of the Bahamas. At least I never heard the word "nuc-you-ler" during the movie. Lastly, they keep calling it the "Demon Rock" or "Doomsday Rock". However, it's made of metal. Even the title of the movie is wrong!
All in all, this movie was actually worse than "Asteroid", which I would have thought impossible. They even stole the idea of the comet collision! How low can you stoop? I won't even bother commenting on the quality of the writing (besides the science), the acting, the special effects and the direction. The Family Channel, being a supporter of family values, should also want our families to get an education. I sure did, watching this. I'll never believe there is a lower limit to the quality of made-for-TV movies again. |
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