What are the chances...? / Discussion

This is the discussion related to the wiki page What are the chances...?.

Asteroid Chance

Alene Y 04 Jan 2012 01:01

That 1 in 200,000 for death by asteroid impact can't be right. I hate to argue with statistics, but I see no way that can be correct. Here is a Bad Astronomy article where he ends up with 1 in 1.5 million.

http://blogs.discovermagazine.com/badastronomy/2008/10/13/death-by-meteorite/

I still think that's extremely high. One man died from falling off his porch in the Tunguska event, so if we consider that an asteroid strike, we could say 1 in however many people have died in historic times. I'm not arguing with you, Astro, but with whoever calculated that number.

Re: Asteroid Chance

FNL 04 Jan 2012 01:45

I also read, 1 in 700,000.

Re: Asteroid Chance

Alene Y 04 Jan 2012 02:57

Yes, that 1 in 700,000 number is also there in the same Bad Astronomy article, but if you go down another paragraph or two, you find the 1 in 1.5 million, which I consider still way off. It has to be 1 in billions, something like what Bikenbeer said.

Re: Asteroid Chance

bikenbeer2000 04 Jan 2012 03:16

I suppose you'd need to produce a figure for the probability of any given area of the Earth being struck by a piece of space rock large enough to kill someone multiplied by the probability of someone being within the danger area at the time. The first figure is probably pretty constant, but the second figure is rising all the time with population and is, of course, also the reason for the increasing number of fatalities caused by earthquakes.

Re: Asteroid Chance

Alene Y 04 Jan 2012 03:24

Yes, to calculate a true probability it gets pretty complicated. It's easier to use historic data. The only problem is where the cutoff would be on the number of people who have died. We only know of one person who ever died because of an assumed meteorite, not an actual impact and not an asteroid, but still…

Re: Asteroid Chance

FNL 04 Jan 2012 03:50

but as astrogeek said…..stop worrying about asteroids…right?

Re: Asteroid Chance

Alene Y 04 Jan 2012 04:12

Right! What we're saying is that the chances are far slimmer than those calculated for that chart. They are vanishingly small. Whoever did that calculation apparently left out a bunch of zeroes.

No one has ever been known to be killed by an asteroid impact in human history, and only one as a result of a meteorite that exploded (the Tunguska event), so the odds couldn't be anywhere near that high.

Re: Asteroid Chance

3WMElliott 04 Jan 2012 13:13

I always thought the 1 in 700,000 was for a single human to have died as a result of an asteroid, as oppose to a specific human.

Loads of things to assume in working it out though - are we to assume the asteroid in question will definitely hit Earth, or do we have to calculate the odds of any given asteroid hitting Earth to the odds of that specific asteroid hitting you in the process?

Re: Asteroid Chance

Alene Y 04 Jan 2012 22:54

True, but we only know of one single human who has died as a result of anything like an impact. It doesn't really matter that he is one specific person, he's the only one.

Re: Asteroid Chance

3WMElliott 04 Jan 2012 23:21

True, but we only know of one single human who has died as a result of anything like an impact.

Do we? Who?

Re: Asteroid Chance

Alene Y 04 Jan 2012 23:38

I'll have to look him up again. It was on old man who fell off his porch from the Tunguska event and died from the injuries. So, as I said, it was only one person we know of who died as a result of anything like an impact and it wasn't even an asteroid.

Re: Asteroid Chance

3WMElliott 04 Jan 2012 23:45

Ah, right. That kinda puts the whole thing into perspective though, considering the odds of dying from a fall, regardless of the cause.

Come to think of it, I wouldn't be surprised if you were more likely to meet your end falling into a crater than being under the rock that made it.

Re: Asteroid Chance

Alene Y 05 Jan 2012 00:13

They seem to waver about whether the man died. I can't find anything documented, only someone saying that the Russian press reported that the man had died the next day from his injuries. Still no name and no credible source.

Here is a paper listing a lot of reports throughout history. I didn't try tallying these to see how many were reported as killed. I still doubt that it would be 1 in 200,000.

http://www.oberlin.edu/faculty/bsimonso/group9.htm

Re: Asteroid Chance

2012hoax 05 Jan 2012 02:22

I'm going to contact the person who made the calculation and ask about his methodology, and also ask if his calculations have changed in the last 6 years or so.

Re: Asteroid Chance

Alene Y 05 Jan 2012 02:44

Good idea, Hoax. I'll be interested to see what they say.

Re: Asteroid Chance

Tomy2011 05 Jan 2012 15:08

Okay, sorry for the ignorance, but I though the asteroid impact chances depend on which asteroid we are talking about. Is the 1 in 200,000 chance an average?

Re: Asteroid Chance

Alene Y 06 Jan 2012 01:09

It should be the odds of any person being killed by any asteroid.

Re: Asteroid Chance

FNL 06 Jan 2012 02:28

So 1 in 200,000 is the odds of any person being killed by an asteroid?
wait……this sure is confooosing.

Re: Asteroid Chance

Alene Y 06 Jan 2012 02:44

Okay FNL, If you wonder what your odds are of dying from a particular cause, that chart shows what they would be. We are just debating the accuracy of the 1 in 200,000 because we don't know that anyone in history has ever been killed by an asteroid impact. The odds for other causes should be pretty accurate because we have records of what people die of.

Some of us are thinking that the odds for death by asteroid impact should be more like 1 in billions, or at least millions, depending on what we include (meteorites, hard evidence?).

Anyway, what it all boils down to is that you should worry more about dying from a fall in the shower or even a chupacabra attack than as the result of an asteroid impact.

Just in case you don't know, I'm joking about the chupacabra attack. They don't exist.

Last edited on 06 Jan 2012 02:45 by Alene Y Show more

Re: Asteroid Chance

FNL 06 Jan 2012 04:23

yes yes yes, thanks for clearing that up for me. :D

Re: Asteroid Chance

bikenbeer2000 04 Jan 2012 02:05

I agree. I'm not aware that anyone in the history of the world has ever been directly killed by an asteroid, so the odds ought to be about 1 in 100 billion. I know that's not quite the way to calculate statistics, but it must be closer to the true figure than 1 in 200,000.

Re: Asteroid Chance

obaeyens 04 Jan 2012 17:16

Well we have 7,000,000,000 people, how many got killed in the last year by a meteorite?
I think it is pretty easy to calculate the risk of you getting hit by a meteorite.

Re: Asteroid Chance

FNL 04 Jan 2012 21:57

Mabye 1 or 2 i guess………..or none….

2012hoax 05 Jan 2012 05:48

I haven't talked to anyone yet, but I did a bit of research, and I think the way he is calculating this is that there is a 1:500,000 chance of an impact event occurring in a given "lifetime". I've seen people calculate that as anything between a 70 and 100 year period. This calculation keeps changing (and getting better) because we are finding more and more of these objects on non-collision orbits, therefore they are factored out of the calculation. A 1:500,000 chance for any 100 year period would be once every 50 million years, right?

I don't know that this is how it was calculated, I'm just making a semi-uneducated guess, fwiw.

Alene Y 05 Jan 2012 06:29

That might be it, but it would still have to reflect a person's chances of being killed even if there were an impact event in their lifetime, not just the odds of an impact in their lifetime. If the object were less than a mile in size, it would have very little chance of killing everyone on Earth. It just seems that with everything factored in, the odds for one person out of nearly 7 billion would be vanishingly small.