There are a slew of direct-to-DVD or Sy-Fy Channel original features on asteroid/comet impacts, and, while they’re not worth going into in detail, it’s worth mentioning a few.
1. Judgement Day (1999). You know you’re in for some real quality when your film stars Mario Van Peebles and pre-SVU Ice-T, plus Coolio for good measure. This movie is.not.good. Every plot element is a cliché, every line uttered a catchphrase. And bad science? You’re soaking in it! [1] An asteroid the size of Kansas City is headed for the Earth, and religious extremists kidnap a scientist to stop him from preventing it from happening, thus fulfilling Biblical prophecy from Revelation. There is only one logical question to ask here: how big is Kansas City? and does that mean the same 2D footprint as Kansas City? The same volume as KC? Oh, ok, they tell us it’s 23km across, so that’s bad news. Of course the government’s gonna nuke it and, since the writers of this movie saw Deep Impact too, it didn’t work. Thanks to an FBI agent and a criminal with connections (Guess which one Ice-T plays… You should be more ashamed of this casting than of the movie itself, producers!), they find the scientist and he saves the day! With…magic? No, with anti-matter technology, and that’s all we’ll learn.
2. Polar Storm (2009) This one combines elements from an impact film with elements from The Core. A comet passes too close to the Earth, disturbing the Earth’s magnetic field. Obligatory scene of people in a brightly lit, tree-shaded, foggy park, looking through a telescope? Check. Science teacher: “Just as our planet has a magnetic field, so does the comet.” That’s just not true. A cometary magnetic field is extrinsic to the comet–i.e., it is induced by the Solar wind. So it get stronger as the comet approaches the Sun, not the Earth. At the distance of the Earth, the strength might be 0.5 milliGauss, or about 5/100ths of a percent of the Earth’s magnetic field strength, and not extending very far from the nucleus. Conclusion: if the Earth’s magnetic field can protect us from the majority of the Solar wind, we would not notice any influence from the magnetic field of a comet that’s induced by, but much, much weaker than, the Solar wind.
As the comet approaches Earth, a piece of it breaks away and heads off in a totally different direction! Conservation of momentum much? Thankfully our hero escapes the blast. Meanwhile, the impact causes the Earth to tilt on its axis, although most people don’t notice. That didn’t happen when the dino-B-gone K-T impact happened, in case you were wondering.
Minor aside: the ~4″ Meade piece of junk telescope they use near the beginning of the film is later noted to cost $4000. It’s hard to tell the specific model, but the telescope pictured appears to be something like this one, with list price of $189 ($169 street). I wouldn’t mention this, except the B-plot of the movie revolves around the price of this ‘scope, which makes it an important detail.
Reporter: “Our trusty sundial… has never been wrong. Until today.” That’s because there is 100% cloud cover. Oh right, and the Earth’s off-kilter. Then the teenagers’ worst nightmare happens: they can’t get cellphone reception. A scientist informs us that the Earth’s rotation axis is out of alignment with its magnetic poles. According to my extensive research, the Earth’s magnetic and rotational axes are already 11 degrees offset, which is why you may have noticed that there’s a difference between magnetic north and true north. Furthermore, we know that the Earth’s magnetic field periodically reverses its polarity, though we don’t know exactly how that happens since we haven’t witnessed it in recorded human history. Ok, back to the movie. Somehow this misalignment causes seismic activity! And it’s leading to…magnetic pole reversal. I swear I typed the part about pole reversal before making it to that point in the film.
Wouldn’t you know it, the government is covering all this up. See? There’s a reason I began this blog with conspiracy theory films. There are lots of weird occurrences around the world as a result of the comet’s impact, but none of the mundane ones. For example, airplanes use magnetic compasses to determine where they’re going. Wouldn’t every pilot in the world have instantly figured out that something was wrong?
I’m not even going to comment on the electrical storms that happen. Let’s instead focus on a bit of good science. During a pole reversal, mini-poles could appear, as in the movie, until the N/S poles stabilize again. And during a reversal, the overall field strength would drop substantially and that could be quite bad. The magnetic field protects us from cosmic rays and other charged particles in the Solar wind. Increased exposure to these things is not good. This is actually the chief concern in sending humans to Mars and beyond. We don’t yet know of any affordable, lightweight materials (you gotta launch ’em) that are effective shields to avoid severe radiation exposure for astronauts on long-duration missions. However, since we’ve never witnessed a field reversal, it’s hard to know exactly what would happen, other than that it certainly doesn’t wipe out life on Earth. There have been lots of reversals in the time that life has been around.
And just when they were doing so well, the scientist hero pronounces Gauss as “goss”. His brilliant plan is to…
Wait for it…
Set off a nuke…
In the Mariana trench, thus realigning the Earth’s magnetic axis? Look, we covered this in The Core review. The Mariana trench isn’t even the thinnest crust location, and it’s near-equatorial location wouldn’t seem to be the ideal location for inducing some sort of torque. They say it needs to be done in the “opposite hemisphere from the comet’s impact”. I’m no geographer, but the thing hit Alaska, so wouldn’t that mean nuking the southern hemisphere? At least there’s an improvement over The Core here: we only need 100 megatons. As a reminder, the largest nuke ever set off on Earth was 57 megatons, but they easily carry the bomb(s) in one box that can be lifted by 2 men. Then the plan works and they save the day.
Sorry–that got a little long so I’ll continue with the next of these awful films in part 3.