Wednesday, July 18, 2007

Useful Warning

For all of you who like to worry about something bad happening, here's something you should really be worried about: Asteroid impacts.

Or rather, the impact of a single large asteroid on the Earth. When it happens, the devestation will be beyond anything you've probably ever imagined. Notice that I said "when" not "if." It is only a matter of time before it happens. There are efforts now to map all the Near Earth Objects that could impact us. But there could be an object an a long eliptical orbit from far out that hits us and we won't necessarily see that coming.

If you ever saw those asteroid impact movies back when they came out - Armageddon or Deep Impact, I think the most important thing to come away with from those movies is that the only fictional part of the movies (aside from the inane characters) was the part where they STOPPED the impact. Right now, if one is coming, there isn't too much we can do about it. Not unless we start doing some planning and designing now. And not unless we find it early enough. Just blowing it up with a nuke isn't going to do it - a nuke wouldn't make even a dent in a sizeable asteroid, and worse, it may just turn one doomsday asteroid into five doomsday asteroids. Think of it this way - say someone fired a shotgun slug at your chest and so to save yourself, while the slug was in mid-air, heading toward your ribs, something blew it up into five smaller fragments, all still on a collision course with your chest at high velocity. Yeah, not much help, that.

The same holds true for anything we could do to an asteroid. A city-sized asteroid may hit the Earth with the equivalent energy of hundreds of millions of nuclear warheads. The energy from a single warhead isn't really enough to put a dent in it. But if we get it early enough, a gentle nudge might be all we need to turn an impact into a near miss.

I don't much go for fear-mongering. Most everything anyone fear-mongers about is bullshit. But asteroid impacts are real and they also really could wipe out all life on Earth, or at least, any life we'd care about (particularly our own). So sitting and doing nothing isn't an option.

It is funny, I once brought this up with some very religious Christianists and they were not worried, they said they knew it would never happen because "god" would protect them. Uh, yeah. Nice way to plan ahead. Others, I'm sure, would look forward to it as the end of the world - something which I find particularly disturbing (especially when you consider that those folks, who read the Left Behind books, have George W. Bush as their idol and they see him as one of them). I could do a whole post on the mental health of that particular line of thinking.

So please, support those who would do something about this. NASA. The Planetary Society. Anyone else who is moving forward. I won't even get into the gamma-ray burst doomsday scenario - there's not much we can do about that one. But then that one only has about a 1% chance of ever happening. The chance of asteroid collision is 100% - it is just a question of when.

8 comments:

armagh444 said...

Setting aside the obvious "gee whiz" factor that always accompanies any foray into a new realm, there is a very good reason why I am adamantly in favor of putting a lot more money into space exploration. I am not a big fan of us putting all of our eggs in one basket, but that's what we've been doing as a species for 4.5 million years now.

DBB said...

Yes, that's a very good point as well. The Earth can't sustain us forever, though I suspect that probably we would not exist as a species by the time the Sun gives out in any case, if for no other reason than we would have evolved into something else by then...

Which reminds me of a quote I love, though I forget who said it - "Earth is the cradle of mankind. But one cannot live in the cradle forever..." or something like that...

ballgame said...

Can I assume that you've seen this Japanese CGI showing what would happen if a somewhat largish asteroid hit us? It's pretty impressive.

Of course, then there's also the Yellowstone supervolcano to worry about. (That link appears to be religiously-affiliated, but its main points seem buttressed by the Wikipedia entry.)

Anonymous said...

Have to agree with the comment by armagh444. The "all eggs in one basket" policy is not a good one. In fact if you think about it most realistic extinction type events (either caused by humanity or naturally occuring) can be side stepped by making sure that we are not all sitting on one lump of rock. Of course trying to get people to understand that this is a ridiculously important reason to spread to other "lumps of rock" is not an easy task

Alex said...

I think humans could probably adapt from asteroid-induced conditions better than, say, the dinosaurs, however. Unless it was a completely earth-shattering impact, which could also happen. I think space exploration is important no matter what, though.

I'm fairly certain I saw something (probably on Discovery) on where scientists were testing whether they could manipulate an asteroid's path. Not blow it up, just "nudging" it, like they do satellites, only on a larger scale.

The Yellowstone volcano pretty much made me happy with my east-coast living, though apparently we now have to worry about a super-tsunami, if there's a landslide on the Canary Islands. You just can't win!

DBB said...

Alex - yes, that's true, humans probably are among the most adaptable animals on the planet, so we may do better than most after an asteroid strike, but even if it only kills 90% or even only half of the planet, things will never be the same again, and life will probably be pretty harsh and unforgiving for many decades afterwards.

But if the asteroid is big enough, no humans will likely survive, or perhaps only a handful on whatever stored food doesn't go bad as the sun is blotted out, crops fail, and whole societies and economies collapse from the mass losses.

If you want to live somewhere safe, well, those tend to be the boring places. There's nothing too exciting about Michigan, but we don't get many tornadoes, we'll never get a hurricane, we don't really get earthquakes or floods - in short, it is dull around here, but safe.

armagh444 said...

I think the point when it comes to any of these plausible catastrophe scenarios is that most of the truly realistic ones (i.e., asteroid/comet impact or eruption of a super-caldera) would impact human civilization in a fashion that would put us back a few millennia. Cormac McCarthy's The Road is actually a pretty good depiction of how bad it would be, though he doesn't actually ever state the cause of the catastrophe. Frankly, I think it's better that way.

DBB said...

It is more fun to leave it somewhat to the imagination with scenarios like that, though the blunt obviousness of an asteroid really doesn't need any funky special explanations or pleading.

I rather enjoyed Stephen King's The Stand - there, it is a plague, man-made, that wipes out most of the planet's population, though the specifics of it are never really gotten into in great detail. It is more about the survivors (and a bit else).

In reality, I don't think a plague would ever do it. Too many people would survive, the survivors would probably be resistant or immune after a while.

I think we'd be put back quite far, though if books and such survived, we probably would recover a lot quicker than millenia in many respects - we'd just take a long time to rebuild infrastructure. We'd have to recycle alot though - most of the easy to get to mineable metals and such are long since mined out. If we couldn't recycle, we'd end up in a permanent stone age...