Astronaut: 'Single-Planet Species Don't Last' 921
An anonymous reader writes "Gemini, Apollo and Space Shuttle astronaut John Young, due to retire in two weeks, says that the human species is in danger of becoming extinct: 'The statistical risk of humans getting wiped out in the next 100 years due to a super volcano or asteroid or comet impact is 1 in 455. How does that relate? You're 10 times more likely to get wiped out by a civilization-ending event in the next 100 years than you are getting killed in a commercial airline crash.' He says that the technologies needed to colonize the solar system will help people survive through disasters on Earth. Young has written about this topic before in an essay called 'The Big Picture'." In related news, the Shuttle overhaul program is on track for a May 2005 launch.
Humans already wiped out -- film at 11000 BC (Score:2, Informative)
So it's almost certain that none of us are here. You're not reading this. Cockroachs are the dominant species on earth.
Re:Odds are off (Score:5, Informative)
Consider that the number of people involved in any particular crash is quite low compared to the number of people on the planet. Thus, while there may be multiple crashes in any given period, the chances of *you* being killed in that crash are quite low.
On the other hand, if you have a single civilization-ending event, by definition the chances of it affecting you are quite high.
So to estimate the impact on *you* in particular, you need to compare
(number of people killed in plane crashes)/(total number of people on earth)*(chance of a plane crashing)
vs
(number of people affected by civilization-ending event)/(total number of people on earch) * (chance of civilization-ending event)
Re:Prove it (Score:3, Informative)
Part of the issue with a couple of them is that a super-volcano eruption can easily make earth 'habitable' but not for us.
Likewise for asteroid impacts.
Leaving the earth "Habitable" does not mean that we can comfortably (or for that matter uncomfortably) live on earth for some period after the event. Earth happens to be "habitable" for a lot of creatures that happen to be extinct because of our own hand right now. Dodos, Passenger Pigeons, etc. As well as being theoretically habitable to creatures we may, or may not have a hand in making extinct, such as Mamoths, and Sabertooth tigers.
The fact that we are at the top of the food chart at the moment doesn't mean that we have to be here.
Super-bombs for astroids, and drilling out preasure for volcanos sounds reasonable, however the fact remains that you still need to find a way to deploy that super-bomb, and get it to the astroid to push it out of it's path towards us. What exactly are you going to do with the preasure you 'drill' out of the volcano? Do you have a plan for it, or are you thinking you can just "release" it in a controlled manner? Kilauea's ben activly erupting since 1983. You can go and watch eruptions relatively safely. It's considered a mild form of a volcano. Mt. St. Helens has had activity overthe past year, and no-one is recomending you be anywhere near it when it erupts. Mt. St. Helens is a small volcano compared to the area considered to be the volcano at Yellowstone. Drilling either to "reduce the preasure" seems a bit unlikely to me.
As far as astroids are concerned, you want to start moving them out of an impact path as far away as possible. Launching a 'super bomb' from earth is a nice idea, but it would be better to have such devices off earth at the time they are needed. (Get them out of the gravitational hole where you have a really small launch window to get them on target.) This means you now have to contend with the activists who are going to fight against the launching of whatever type of 'super-bomb' you plan on putting into orbit. Have fun.
Then again, that's just me.
-Rusty
Re:1 in 455? (Score:5, Informative)
The probability is not 100% it is in fact 20%.
Chance of no event in a 455 year period: 454/455 = 99.8%
Chance of no event in 100 such periods: (454/455)^100 = 80.3%
Hence chance of an event in 100 such periods: 19.7%
Using your whacked out mathematics I guess in 100000 years the probability of at least one event is 200%?!?
Re:Prove it (Score:1, Informative)
The fact the parent post has been moderated up to a high "Insightful" shows how stupid the average Slashdoter is. We know for a fact thousands of species on Earth have been made extinct by the sort of events being talked about.
We also know for a fact that the amount of energy required to avert an incoming asteroid far exceeds what we have available or are likely to have available in a useful form (i.e., there might be enough geothermal energy available but we couldn't extract it fast enough). Blowing up such an object wouldn't change the course of the majority of the fragments which will still destroy us. The notion of drilling out the pressure of volcanos just displays an ignorance of geology.
To the average Slashdot reader: please either get educated to the point where your comment on issues such as this matters (i.e., become an engineer or at least a physicist) or leave such issues to those who have a clue.
Re:In A World Where... (Score:3, Informative)
I suggest you go read up on Lord Kelvin and his attempts to prove that the Earth couldn't possibly be millions of years old. He argued, quite convincingly at the time, that when you accounted for all known incoming and outgoing heat, the earth couldn't be more than about 10,000 years old or it would have frozen solid. And it is true that the earth is slowly cooling off, as the Sun doesn't provide enough warmth to keep our temperature this high.
Lord Kelvin was almost right. If there were no variables other than those he knew of, the earth would indeed have frozen solid in 10,000 years or so. But he performed those calculations before the discovery of a process called 'radioactivity', by which the nuclear decay of various substances produces very substantial amounts of heat. And fortunately the Earth has an absolutely incredible amount of radioactive material, the slow decay of which keeps us nice and toasty.
So, A) vulcanism is very much related to radioactivity. The earth would have frozen solid by now otherwise, and there would be no volcanoes. And B) while you're correct that the heat isn't caused by a nuclear reaction (rather decay), nobody said it was. The parent was talking about exactly what I explained here.
Re:45,500 Years = 100% chance of human wipe-out (Score:3, Informative)
There is a 45,499 out 45,500 chance of actually surviving a given year. This equates to a 99.9978% chance of survival. This percentage is then taken to the power of the number of years you want to survive.
In this case to survive for 45,500 years with these odds you would have 99.9978% ^ 45,500 = 36.7875% chance.
So your chance of actually being wiped out would be 63.3212% instead of the 100% certainty of death. The odds a little better but not much.
Re:Forgetting something? (Score:3, Informative)
~Philly
Re:Prove it (Score:3, Informative)
If done early enough, they wouldn't have to be "super bombs." They could simply be small thrusters. If you nudge the asteroid early enough, you can prevent the collision.
Take an example. Say two cars are speeding straight towards each other on a foggy one-lane road one night, with their headlights out. They're a mile apart and they're both going 60 mph, straight at each other. By the time they see each other, they'll need to slam on the breaks or crank the wheel hard, expending a tremendous amount of energy to avoid the collision. However, if they knew from the beginning, when they were a mile apart, that they were on a collision, course, all one of them would have to do would be to turn their steering wheel 1 measly degree, and they'd miss each other. Sure, it would be close, but they'd still miss, and never cross paths again. THAT is the approach we need to take to asteroids. We don't need to obliterate them or split them in half. We need to see far enough away (10 years) that a collision is imminent, and "nudge" it a little. Just slow it down by a few miles-per-second such that instead of smacking into Earth when we come around, we'll have already passed by, and it will miss.
Re:Prove it (Score:3, Informative)
Yes you are correct. It also refers to any self-replicating machine.
From the Wikipedia [wikipedia.org]
A few self-replicating space probes, Von Neuman pondered, could explorethe galaxy in only a few hundred thousand years.
Re:How'd they get 1 in 455? (Score:5, Informative)
In fact, a 1 in 455 chance of humanity being wiped out in each successive 100 year block gives us a 454 in 455 chance of surviving that 100 year block.
Our odds of surviving 200 years is the odds of us surviving the first block (454 in 455) times the odds of us surviving the second (another 454 in 455) - about 99.5%
In other words, the odds of us surviving 100n years is (454/455) ^ n. The odds of us making it through the next millennium, then, is (454/455) ^ 10; that equates to about 44 in 45, or a one in 45 chance of our species being wiped out before we see the next millennium bug.
The odds at 10000 years (n=100) diminish to about one in five that we'll all have been wiped out - that is, four in five that we're still here.
Around the 30 000 year mark, the chances we're wiped out are pretty much even. That would mean we'd tend to expect mass extinction events about once every 60000 years, on average. you could consider that as a kind of indicator as to the validity of the original statistic.
Beyond that point, it becomes easier to quote the odds we're still here than that we're not.
After 100 000 years, we get down to about a one in ten chance of still existing. In other words, out of all the possible ways the next 100 millennia could go, only one in ten of them finish with us still existing.
In other words, the number predicts survival is unlikely, but it's not impossible, and the odds keep dropping, but they don't reach zero.
Whether the 1 in 455 number is right or not is open to question, of course, but just because we've been around more than 45500 years is no reason to dismiss it completely.
Re:Prove it (Score:2, Informative)
Re:Prove it (Score:3, Informative)
No it's not. But must (and I realize you were weren't doing this) people who bring up the Bible to do stuff like defend marriage claim it defines marriage as between a man and women. When it's really between a man and his wifes (concubines allowed), according to the bible.
And the concubines issue comes up again. It's technically adultorous, but it's still allowed. In Leviticus it's stated that being married doesn't prevent a man from taking concubines (read mistresses or extra marital affairs).
Polygamy isn't socially accepted nowadays though
Depends who you hang with. I know quite a few polyamorous people.
Abraham's illegitimate children were fathered by Hagar right? Whom Serai forced upon her husband, and then drove out into the desert when she got jealous? I thought Abraham had tacit approval from God to sleep with Hagar? And don't you think it's kind of cruel to punish millions of descendents because Abraham slept around? Abraham himself was never directly punished, or sent to purgatory or hell.
Re:In A World Where... (Score:3, Informative)
Re:Prove it (Score:1, Informative)
The U.S. would have had a negative population growth rate as of the 1970s. However, immigration has resulted in a MASSIVE population growth in this country. See NumbersUSA [numbersusa.com] for the details.
People who live in the U.S. today, who are under 20, are completely screwed as far as their quality of life is concerned.