Don't Throw Rocks: Asteroid, Deep Impact, Armageddon

Steven Dutch, Natural and Applied Sciences, University of Wisconsin - Green Bay
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Rating Symbols

HBS

Hot Babe Scientist. Linus Pauling never looked like this. Hollywood is now capable of dealing with a woman scientist. Someday they will be capable of portraying a plain, middle-aged or overweight woman scientist.

HUNK

Hunk Scientist. Linus Pauling never looked like this, either. Stephen Hawking may be a great heroic role model, but good looks sell tickets.

HCIM

High Caloric-Intake Monster. Large animals eat a smaller fraction of their body weight each day than small ones, a manifestation of surface to volume ratio. Hollywood critters, on the other hand, eat like shrews.

PAPWL

Pompous Ass who Pays With His Life. The pig-headed boss or political figure who refuses for selfish reasons to listen to warnings and gets killed. Occasionally it really happens; the governor of Martinique refused to evacuate when Mont Pelee began erupting 1902, and died in the resulting catastrophe. So did 30,000 innocent people.

SK

Superfluous Kids. Kids (generally repugnant) who serve no real dramatic purpose except to generate audience sympathy. I root for the monsters, especially when the kids do something stupid after they've been told not to.

CCHNC

Cookie Crumbs Have No Calories. And large objects (like asteroids) cease to exist once they're broken up.


Asteroid (HBS, CCHNC)

Where do I begin? In this movie, originally made for TV, a comet disturbs the orbits of several asteroids and sends them headed toward earth, but their exact paths aren't known because in this alternative reality, ballistic paths are very unpredictable. When alerted, the director of FEMA says "we only deal with immediate threats" as if nobody has planned for this scenario, or as if disasters more than ten minutes in the future aren't "immediate" (well, this is FEMA, after all).

At that point I decided to do something else for a while. When I came back, Kansas City was being evacuated. The incoming asteroid breaks up and one piece ruptures a dam (where did the other pieces go?). High drama: a fire truck making a last-minute sweep collides with a vehicle, sustains a dinged bumper and scratched paint, and is "disabled", so the firemen have to be rescued. The flood comes. I was struck by the realism - never before have I seen such a realistic depiction of water being poured on an HO-gauge train layout. The Air Force has thrown its full resources - two C47's - into the evacuation effort (maybe the Defense cuts have gone a little too far?). With the danger over, the director of FEMA says to be careful: "We don't want to promise anything we can't deliver." (Now when has FEMA ever done that?)

But we're not out of the woods yet. Asteroid Eros is headed for Earth. An experimental laser system designed for defense against "tactical ballistic missiles" (which have ranges, by definition, of only a few hundred miles) is used to destroy the asteroid. The ring-shock-wave from Star Trek VI has become a sci-fi cliche. AND NOBODY ASKS WHERE THE PIECES ARE HEADED! NORAD, which can track football-sized objects as far as the Moon, can't see them. It comes as a real shock when the heroine learns that there are still pieces headed for Earth. Of course, their paths can't be predicted because the gravity of the Sun and Moon are affecting them unpredictably, but as the episode closes, a lot of small hits have occurred and a big piece is about to hit Dallas.

The irony here is that none of the gobbledygook is necessary to the plot; it would be perfectly feasible to dub in entirely new, scientifically-accurate dialogue. This is ineptitude bordering on hubris; the writers seem to have decided to have a go at it with no scientific consultation whatever, possibly even to violate scientific laws whenever they could. The result is world-class ineptitude. The writers appear to have said "Scientists? Scientists? We Don' Need No Stinkin' Scientists!"

The drivel about orbits reinforces my belief that the average American really doesn't believe in cause and effect. There seems to be a widespread belief that gravity and inertia hold planets in orbits by only the most tenuous thread, and the slightest disturbance (maybe even absent-mindedness) will send them wandering off. To a physicist, of course, orbits are as fixed as if the object were on rails.

The second half of the movie is fairly straightforward. After Dallas is cratered, the rescue efforts begin. As someone who can barely keep a campfire or fireplace going, I marveled that tiny scraps of debris were still burning twelve hours after the impact, but by the scientific standards of the first half of the movie, that's small potatoes. The most realistic scene in the whole film comes when a FEMA man is shot by an irate citizen who's angry that relief efforts aren't moving faster. At the very end, the comet that sent debris careening toward Earth appears in the sky, moving visibly, of course.

Deep Impact (SK)

The more scientifically accurate (and bland) of 1998's impact films. The creators said they were trying for the emotional impact of On the Beach, but they didn't quite get there. Maybe they couldn't - On the Beach, a classic Cold War apocalypse film, dealt with humanity facing creeping death from the fallout of a nuclear war, and much of the film's poignancy dealt with the fact that it was our own stupidity that got us into the mess. However much the world is threatened by an asteroid impact, it's not our fault. And the impact of On the Beach is heightened by not having a happy ending, something this film couldn't quite bring itself to do.

Some of the worst scientific bloopers occur in the first few minutes. After an amateur astronomer discovers a comet, the news is relayed to an observatory for confirmation. The astronomer who confirms the comet discovers that it will strike Earth. With the phones out (he has e-mail but has to communicate by phone?) he drives frantically down the mountain, only to die in a flaming wreck. In reality:

The secret comes out when a reporter (Tea Leone - lovely as a marble statue and with roughly the same emotional range) overhears references to "Ellie," and thinks she's got a hot story on the President having a mistress. "Ellie" turns out to be an acronym for ELE, or Extinction Level Event. One of the best things about this movie is we have a black President (Morgan Freeman) and nobody bats an eye. The President decides it's time to go public, and Leone is suddenly thrust into journalistic superstardom. Very strange, since she stumbles at the mike like an eighth-grader reading a book report.

The mission to try to divert the comet uses an Orion propulsion system. This is a real scheme, still the only known way to accelerate large masses in space quickly. It uses small nuclear explosives. Arthur C. Clarke wrote that Stanley Kubrick briefly considered using an Orion propulsion system in 2001: A Space Odyssey, much to the terror of the special effects people. Clarke went on to relate that Kubrick dropped the scheme, joking that people might think he'd taken the advice from one of his earlier films - Doctor Strangelove - and really had "stopped worrying and learned to love The Bomb." But why go to the trouble of building an Orion propulsion system and then not give the ship enough fuel and explosives to deal with any contingency? 

The comet is portrayed as violently erupting when the Sun hits it. Now comets do outgas when warmed by the Sun, but it's very unlikely that they turn on and off instantly. Once warmed, frozen gases should still vent on the night side of the comet. Ice is a good insulator and porous ice in a vacuum should be a very good insulator, so volatile materials deep beneath the surface will not heat up quickly. Still have doubts? Get some dry ice from a refrigeration company. Put it out in the Sun. Watch it explode. Let me know how long it takes. Also go on the Internet and find out how many icebergs have exploded recently when exposed to sunlight.

The Sun in space is no brighter than the Sun on Earth and a momentary glimpse will not blind an astronaut permanently, unlike what happens in the film. The comet is only 20 light seconds away when the astronauts land on it, or 6 million kilometers, not enough for it to be significantly closer to the Sun than earth is. Anyway, most people shut their eyes involuntarily in extremely bright light, so only an extremely determined and stupid astronaut would stare into the sun long enough to be blinded by it.

The nuclear explosion set to destroy the comet merely splits it in two. I find it very hard to believe that splitting the comet would not also divert the pieces by the paltry few thousand kilometers needed to miss the earth. When all else fails, the President announces Plan B, a huge underground complex for selected people. What is it with the underground thing? This is not On the Beach - there's no radiation to hide from. Above-ground shelters would be much cheaper and just as effective. And although this is supposed to be a film about a global disaster, it deals mostly with people who work in clean offices and offers only snippets of video dealing with the gradual breakdown of civilization. Apocalypse Lite.

The impact and resulting wave are quite well done. The only quibble is that an incoming object that size would radiate so much heat and light that viewers would be blinded and objects in the open burned. And the acid rain this thing will produce from nitric oxide will be something else. Also a wave that big will displace a huge volume of air and will be preceded by hurricane force, if not tornado force, winds. The wave hitting New York is worth the price of a ticket. (The original showed the World Trade Center being submerged and then re-appearing after the wave passes; this scene was cut when the movie showed on television.) One nice touch of detail: in an overhead shot of the wave inundating Manhattan, tiny specks on a skyscraper rooftop move away from the wave (spectators trapped on the roof trying to find refuge).

A CCHNC award for the ending. The larger of two chunks is destroyed and the pieces come raining in. Now they may not reach the Earth's surface, but they will deliver the same amount of energy as the original piece. The incoming ejecta after the asteroid that killed off the dinosaurs delivered radiant heat equivalent to a kitchen oven all over the planet.

For this film to have achieved the impact of On the Beach, it should have started with the full impact and dealt with the plight of survivors as they faced increasingly hopeless odds. In fact, showing the creeping advance of global darkness after the impact would have been almost exactly analogous to On the Beach.

Armageddon

Not as well-received by critics as Deep Impact. There's way too much vibrating camera action and the scientific bloopers come thick and fast. Ironically, I think it did a better job of dealing with the global human drama than Deep Impact, for the simple reason that it actually showed scenes outside the U.S. One reviewer lambasted it for focusing solely on American males, apparently failing to notice the female Shuttle pilot and the Russian cosmonaut.

The treatment of the Russian space program is just plain insulting and is the worst blot on the film.

Nothing is going to divert an asteroid the size of Texas, and particularly not a "rogue comet." An object that size is not going to remain undetected until only 18 days from impact. This object is 1/10 the diameter of the Moon - at ten million miles away it will still be visible to the unaided eye. And the puny force of a nuclear weapon won't have any effect at all.

The impact is described as killing half the Earth by heat and blast and freezing the remainder to death in a nuclear winter. An asteroid 10 kilometers across might do that - one hundreds of kilometers across would vaporize the oceans and huge amounts of rock. The Earth would have a temporary atmosphere of live steam and vaporized silicate rock. It would literally shine like the Sun briefly. Everybody fries.

The film would have us believe NASA and other scientists have never considered this problem. Anyone who would propose using a solar sail to divert an asteroid only days from impact, as one purported NASA scientist does in a brainstorming session, shouldn't be allowed near a Fourth of July sparkler, much less a real rocket.

Nobody in the U.S. Government apparently knows how to drill in rock; not the U.S. Geological Survey, not the Department of Energy. And someone with years of experience drilling for oil in sedimentary rocks is going to have a finely-honed intuition for drilling in the silicate rocks and metal of an asteroid. Right.

The geologist in the crew is told to expect "razor-sharp rocks", which are duly served up in plenty. Now where, in millions of images of dozens of Solar System objects in four decades of space exploration, is there a single razor-sharp rock? Everything in space, including the  asteroids so far imaged close-up, is rounded by micrometeorite impact.

Judging from the way people get sucked out of one wrecked shuttle, NASA has never heard of seat belts or safety tethers.

Meteors "the size of basketballs and Volkswagens" don't come screaming in like artillery shells. They would be braked in the atmosphere, especially along low-angle paths like those in the movie, although they would still fall as hard as any other large rock dropped from a great height. And a CCHNC award for the end, where the small pieces are dismissed casually ("mostly vaporized") even though similar sized pieces wrecked New York at the start of the film. It's a pity. New York, which is in the best shape it's been in in decades, gets waxed in both films.

Dropping the Chrysler Building was great (I despise Art Deco) and the destruction of Paris is spectacular. I'm glad I got to see it while it was intact.


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Created 5 February 1998, Last Update 02 June 2010

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