2004 MN4 Asteroid Odds Inching Up Again

bfwebster writes "The latest update from NASA now gives 2004 MN4 a 1-in-37 chance (probability of 2.7%) of hitting Earth on April 13, 2029. That's a bump up from the 1-in-46 (2.2%) odds given this weekend and almost a 10x increase in probability from the original 1-in-300 odds announced late last week. Interesting times, indeed."

Comments

Impact energy

[b1t r0t]

One and a half gigatons. Nice. Even if it landed in an ocean, it would still make quite a splash.

Re:Impact energy

[Billly Gates]

Try a tsunami about 500x times bigger almost a mile high traveling 20 miles inland destroying everything in its site.

Keep in mind 90% of the population lives within 100 miles of the coast.

Devestating indeed.

Re:So what happens if reaches 100%?

[way2trivial]

at 300m across, it can be moved without a nuke

gosh, maybe even just a little 'love tap'

delta V is a function of how hard you smack it, and from how far away..

Re:Strange questions....

[dustinbarbour]

Though you are correct, I don't think an asteroid of this size would obliterate the moon. As such, life on Earth would remain largely unaffected I should think. If we were lucky and it hit the bright side of the moon, we may no longer have the so-called "Man in the Moon", but that would be a small price to pay to see such a terrific impact on a body so close to Earth.

The probability *should* rise before falling

[da cog]

Just because the probability keeps going up, it doesn't mean that we are getting increasingly sure that the asteroid will hit Earth. Suppose that the asteroid were going to come close to Earth without hitting it. At first, the impact probability would appear low since the "window" of orbits allowed from the data would be wide. As we got better observations, however, this window would shrink, but the Earth would stay inside it since it's near the center. Thus, for a time the probability of impact would go up, since the Earth would take up a greater percentage of the window. Eventually, though, the window would shrink past the Earth and the probability would go down again.

I suspect that this is what will happen. Could easily be wrong, though.

Inching up is to be expected

[xihr]

Keep in mind that the very nature of the situation will result in the probability slowly creeping upward until (hopefully of course), it is eliminated entirely. The very nature of having a low-probability situation whose likelihood has to be determined with continued measurements to increase the precision of the prediction means that as the likely set of paths is refined, the cylinder that represents the likely set of paths of the asteroid shrinks. Because it shrinks, the probability that it will be at any given point in that cylinder goes up.

At the point when the cylinder is projected to miss Earth entirely, the probability of impact will suddenly go to (very near) zero. In other words, the very nature of the situation regarding refining the data we have means that the probability will creep slowly upward before it goes to zero. (This happens for all close encounters, of course; it's just that no one's watching the actual probabilities for those too carefully.)

So the steady rise of the impact probability may be disquieting, but it is not unexpected and does not actually indicate anything particularly additionally troubling going on.

Re:I can only wonder

[cmowire]

See, I think that there's a difference and a gift in disguise here.

The reason why we don't have a system to deflect asteroids right now is because asteroids are one of those things that "could happen" in the far off future.

It's like smoking. It's not guaranteed to kill you, and nobody drops dead after a single puff. Some smokers live really long lives. So smoking is viewed as something that's "bad for you", not an instant death sentence.

Therefore, we've got a lot of people who smoke in the world.

However, pulling out a shotgun, pointing it at your face, and pulling the trigger is unquestionably lethal.

Therefore, the only people who do that are people who really want to die.

The difference is that we don't always think about things that *might* cause harm, but we always think about things that *will* cause harm.

This is just one of the many ways that the human brain is a little screwed up about risk management. It worked when we were on the plains of Africa and needed to evade predators and manage to survive, but it doesn't necessarily hold up now.

Now, the blessing in disguize is that a quarter century is very much long enough to figure out what to do. Remember, we've got more than enough knowlege to do it -- computers to plot trajectories, a variety of tested and untested propulsion and power systems, techniques, etc. In the quarter of a century timespan, we may just need to paint one side white to provide the push. So, in some sense, it's even easier than trying to go from nothing to the moon landing.

But what we lack, like most things in space, is a feeling of urgency to really do something about it. Thus, this is a blessing in disguize. If they give it a decent possibility of really hitting Earth, 25 years in the future, we've got time to do something about it in ways that if they said that it'll probably hit tomorrow we won't.

Same way I know several folk who, when their doctors told them that they were going to be dead in x years if they didn't quit smoking, were able to go cold turkey.

Re:Space Soap Opera

[pclminion]

This is funny, but it also raises an important point that many people seem to miss.

Last time I took part in a discussion about asteroid impacts, it was suggested that people who are rich enough would be able to simply buy their way off the planet before the disaster strikes. As in buy with money.

Think about it. There's a gigantic rock hurtling toward Earth. There are only enough spaceships (let's say) to take 1,000 people off the surface. All life as we know it on Earth is about to be destroyed. Do you: A) Get on your spaceship and get the hell out of there, or B) Accept pieces of paper with dead presidents printed on them in return for allowing other people to get off the planet?

Even if you survived the ensuing destruction, what good would those little pieces of paper be?

The rich sometimes seem to think they can buy their way out of any problem, but the total destruction of Earth isn't something that money will save you from.

Hello, 23,000 killed in tidal waves?

[raehl]

Mainstream media can only handle one natural disaster at a time, and the one that happened NOW is more important than the one which has a 2.7% chance of happening in 25 years.

Also, we should expect the probability of impact to continue to increase until it either goes to zero (most likely) or 1. This asteroid has a sigma of 0 - that means the MOST LIKELY path is impact. More observations are most likely going to eliminate the outlying paths first, so as we eliminate more and more of the outlying paths of possibility the most likely path will be more and more likely.

Until we get the observation that says "Ah, yeah, definitely going to miss", and then it'll be zero again.

Re:I can only wonder

[aminorex]

Since global warming has already been observed, I'd say the chances are about 1 in 1.

More interesting is whether a methane burp from clathrates will result in a cascade leading to a global extinction event during your lifetime.