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Space Earth

Asteroid Impacts Bigger Risk Than Thought 172

Rambo Tribble (1273454) writes "The B612 Foundation, a U.S.-based nuclear test monitoring group, has disclosed that their acoustic sensors show asteroid impacts to be much more common than previously thought. Between 2000 and 2013 their infrasound system detected 26 major explosions due to asteroid strikes. The impacts were gauged at energies of 1 to 600 kilotons, compared to 45 kilotons for 1945 Hiroshima bomb."
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Asteroid Impacts Bigger Risk Than Thought

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  • by Anonymous Coward

    Between 2000 and 2013 their infrasound system detected 26 major explosions due to asteroid strikes. The impacts were gauged at energies of 1 to 600 kilotons, compared to 45 kilotons for 1945 Hiroshima bomb.

    Is the Earth basically getting nuked (in terms of explosive yield) about twice per year without anybody noticing?

    • by tomhath ( 637240 )
      I'm pretty sure the people in Russia noticed that one last year. But yea, when it releases that energy high in the atmosphere it doesn't usually do any damage on the ground. Plus about 70% of the time it happens over an ocean.
      • by beelsebob ( 529313 ) on Wednesday April 23, 2014 @11:18AM (#46824527)

        70% of the time over the ocean, 99.99% of the time over somewhere that isn't populated. It's a 1 in 10,000 occurrence that this happens over a populated area. Given a rate of 2 a year, that means once every 5000 years on average, and many of these will not do any damage. So I'd say this is pretty much pure hype.

        • by MozeeToby ( 1163751 ) on Wednesday April 23, 2014 @11:23AM (#46824609)

          About 3% of the planets land area is considered "urban". Taking into account the oceans that makes for right around 1% of the total surface area of the planet. That means that any given year there's about a 2% chance of an asteroid explosion happening over a major population area. That means a 1/3 chance of a significant (greater than 1 kiloton) explosion over an urban area over a 50 year time span. That's not crazy high, and most of those will occur at high altitudes, but it's certainly not once in 5000 years.

          • by ThreeKelvin ( 2024342 ) on Wednesday April 23, 2014 @11:48AM (#46824907)

            Your math is off. If your numbers are correct, the risk of having at least one meteor over an urban area during those 50 years is:

            P(N>1) = 1-P(N=0) = 1-(1-0.3*0.03)^100 = 60%

          • I would say that the tsunami that would result from an ocean impact would be broadly devastating, and damage a large number of dense urban areas. How much of the ocean's surface area is a serious risk, would you say?

        • Comment removed based on user account deletion
      • Comment removed based on user account deletion
        • by GNious ( 953874 )

          from some reports, significant amount of people were hurt from seeing a bright flash, and the running to the windows to look out ....

    • You can explode 600 kilotons every year without anyone but satelites noticing.

      • by ackthpt ( 218170 )

        You can explode 600 kilotons every year without anyone but satelites noticing.

        I see them, now and then, during the daylight hours, but you have to be looking up and in the right area to spot them. Some are pretty exciting to see.

    • by geogob ( 569250 )

      That's bound to happen when those who can notice are found in less than 75% of the the surface of the planet.

    • Once difference is that the energy is spread out over kilometers rather then all at one point near the surface.

      This Quirks and Quarks story on the The Chelyabinsk Meteor [www.cbc.ca] talks about this and how the data suggests impacts are more common then we thought.

    • No. The B612 people's math is demonstrably wrong, or at least very misleading.

      26 explosions happened in the atmosphere in the last 13 years. Some of them broke windows but none had significant impact on cities, and would not have no matter their location. I don't know how they predicted once every hundred years, but they're wrong for two reasons. First, predictive analytics just doesn't work that way with any high confidence. If I flip a coin -- one that I know is cheating -- 26 times and it comes up h

      • No. The B612 people's math is demonstrably wrong, or at least very misleading.

        ...There are only a few hundred noteworthy craters on earth over the past few hundred-million-years. That works out to "not one per century".

        Make no mistake -- I think we should prepare for and defend against them, and I'm in favor of the satellite and conversation on the topic. But the numbers in this study are difficult to swallow and I accuse the hopefully well-intentioned people behind B612 of some under-founded alarmism.

        Did you actually read the article? The statement from B612 was "The foundation says the CTBTO data would suggest that Earth is hit by a multi-megaton asteroid - large enough to destroy a major city if it occurred over such an area - about every 100 years." Since there was a very famous one just over a century ago in Siberia (1908) that most definitely would have destroyed a major city if it had been hit it is not all obvious that there is any exaggeration here. And notice that it did NOT leave a crater. Com

  • by Anonymous Coward

    The B612 Foundation [b612foundation.org] is a private venture dedicated to finding NEOs that will impact the Earth. They used nuclear test monitoring equipment to find the explosions resulting from asteroid impacts.

    • by rossdee ( 243626 ) on Wednesday April 23, 2014 @11:20AM (#46824547)

      Maybe some of those events were earthquakes. I find it hard to believe that their were 26 major impacts that we didn't know about. 600KT is hard to miss even if it is in a remote area.

      • by mveloso ( 325617 )

        According to B612 they were all airbursts. I wish they'd make their data public, so people could take a look and see.

      • Maybe some of those events were earthquakes.

        Implying that you think that seismologists are incompetent.

        Seismologists have been doing this since the early 1950s. It isn't rocket science, and it is comprehensively automated. If the NTBTO thinks they're airbursts, not earthquakes, then it's very likely that they're airbursts, not earthquakes.

        One of the characteristics that is used to differentiate an airburst (or other large explosion) from an earthquake is the distribution of first motions. For an explosion

  • If our planet is absorbing these impacts, and therefore converting the potential energy into something else, what's the (previously-unmeasured) impact of that?

    For example, what if that energy became heat?

    • Re:How much energy? (Score:4, Informative)

      by by (1706743) ( 1706744 ) on Wednesday April 23, 2014 @11:27AM (#46824661)
      600 kilotons TNT is about 2.5e15 J. In comparison, the sunlight incident on the Earth is around 174 petawatts, meaning it takes roughly 20 milliseconds for that much solar energy to be absorbed (clouds, oceans and land masses) by the Earth (taking into account the ~30% reflected power). In comparison, the total world annual energy consumption is around 5e20 J. So, I wouldn't be too worried about added heat due to asteroids.

      Sources:
      https://www.google.com/search?... [google.com]
      http://en.wikipedia.org/wiki/O... [wikipedia.org]
      http://en.wikipedia.org/wiki/S... [wikipedia.org]
    • blame the asteroids for global warming!
    • I doubt it's significant but hey, math is fun so here we go!

      They don't really say what the distribution of the impacts was at least not in a way that's easily accessed, statistically it's likely to be mostly smaller impacts but like I said, I doubt the answer will be significant so lets do an absolute worst case of 2 600 kiloton events every year. That makes 1200000 tons of TNT worth of energy every year. Google tells me 1 ton of TNT is equal to 4.18 gigajoules of energy so that comes out to 5*10^15 joule

  • 1-600 kilotons (Score:5, Informative)

    by Arancaytar ( 966377 ) <arancaytar.ilyaran@gmail.com> on Wednesday April 23, 2014 @11:15AM (#46824455) Homepage

    8/25/2000 (1-10 kilotons) NORTH PACIFIC OCEAN
    4/23/2001 (1-10 kilotons) NORTH PACIFIC OCEAN
    3/9/2002 (1-10 kilotons) NORTH PACIFIC OCEAN
    8/9/2006 (1-10 kilotons) INDIAN OCEAN
    9/2/2006 (1-10 kilotons) INDIAN OCEAN
    10/2/2006 (1-10 kilotons) ARABIAN SEA
    12/9/2006 (10-20 kilotons) EGYPT
    9/22/2007 (1-10 kilotons) INDIAN OCEAN
    12/26/2007 (1-10 kilotons) SOUTH PACIFIC OCEAN
    10/7/2008 (1-10 kilotons) SUDAN
    10/8/2009 (>20 kilotons) SOUTH SULAWESI, INDONESIA
    9/3/2010 (10-20 kilotons) SOUTH PACIFIC OCEAN
    12/25/2010 (1-10 kilotons) TASMAN SEA
    4/22/2012 (1-10 kilotons) CALIFORNIA, USA
    2/15/2013 (>20 kilotons) CHELYABINSK, OBLAST, RUSSIA
    4/21/2013 (1-10 kilotons) SANTIAGO DEL ESTERO, ARGENTINA
    4/30/2013 (10-20 kilotons) NORTH ATLANTIC OCEAN

    yyeeeah, those are technically all between 1-600 kilotons.

    Also, between 1 kiloton and 600 gigatons.

    • by Jack9 ( 11421 )

      Nothing landed at 600 kilotons. That event would have been noticed, so I'm not sure about the purpose of the hyperbole.

      • by CanHasDIY ( 1672858 ) on Wednesday April 23, 2014 @11:29AM (#46824689) Homepage Journal

        Nothing landed at 600 kilotons. That event would have been noticed, so I'm not sure about the purpose of the hyperbole.

        Between 1 and 7,000,000 people who read OP's post got the point.

      • Comment removed based on user account deletion
      • by cusco ( 717999 )

        The Eastern Mediterranean Event [wikipedia.org] was a 12-20 kiloton explosion over the Mediterranean Sea in 2002. It occurred during a period of tension between India and Pakistan, and if it had arrived a few hours later and exploded over that region it would almost certainly have been interpreted as a nuclear attack.

        • if it had arrived a few hours later and exploded over that region

          Earlier, surely? Last time I looked, India and Pakistan (and their mutual border) were east of the eastern Mediterranean.

          Is the latitude right? I think it's a bit too far north. [Checks] It could have just clipped into Jammu and/ or Kashmir, which would have been ... very troubling.

    • Re:1-600 kilotons (Score:4, Interesting)

      by darkshot117 ( 1288328 ) on Wednesday April 23, 2014 @11:48AM (#46824899)

      I'm not sure why that data cuts off at ">20 kilotons", which seems to hide the fact that Chelyabinsk was measured to be 400-500 kilotons. >20 seems to be a bit of an understatement here.

      • Perhaps it is detector saturation.
        • With 60-odd infrasound detectors, if the nearest ones were saturated, then the next one on a particular azimuth from the epi- (or hypo-) centre should have picked it up. Considering that Chelyabinsk is and was one of the major industrial centres where the Russian nuclear arsenal was built, one would rather expect it to have pretty fair coverage.
      • 20 kilotons is probably the upper limit of what their detector can handle. ">20 kilotons" is simply a way of expressing "off the scale".

    • by hAckz0r ( 989977 )
      Yes, and the story line would have been a lot different if they had just come out and said that only two were greater than 20 kilotons. Now compare that fact with the statement "Hiroshima was a 15-kiloton device" to put things more in perspective. Granted, you don't want one falling on your city, but it isn't going to kill millions more with deadly radiation after the impact either. Its the aftermath of the A-bomb that was so gruesome. Until the asteroid gets big enough to create a 'nuclear winter' the ris
      • by cusco ( 717999 )

        Its the aftermath of the A-bomb that was so gruesome.

        No, it was the actual event that killed almost everyone, residual radiation killed relatively few compared to the initial blast. I highly recommend the US Army's Strategic Bombing Survey's work "THE ATOMIC BOMBINGS OF HIROSHIMA AND NAGASAKI" [gutenberg.org], the definitive work on the subject and about as horrible a read as you'll find.

      • by dryeo ( 100693 )

        As another poster pointed out, one at the wrong time and place could trigger nuclear war. His example was http://en.wikipedia.org/wiki/E... [wikipedia.org] which to quote,

        The event occurred during the 2001–2002 India–Pakistan standoff, and there were concerns by General Simon Worden of the US Air Force that a similar explosion could have sparked a nuclear war between the two countries, had it exploded over Pakistan or India, which would have devastated both regions and caused over 10 million deaths.[2]

  • Not impressed (Score:2, Informative)

    by Anonymous Coward

    First, the Hiroshima bomb was 13 Kilotons, not 45. Nagasaki was roughly 20 Kilotons.

  • Headline: asteroid strikes bigger risk than thought.

    If I find a magic lamp one day the first thing I'm wishing for is not rustproof +2 grey dragon scale-mail but the removal from existence of click-bait. Hint: "asteroid strikes more common than thought" would have been interesting enough to get me here, morons.

  • I don't think the word 'risk' means what they think. If no one is noticing, it doesn't seem like there's much risk
    • Re:risk (Score:5, Insightful)

      by almitydave ( 2452422 ) on Wednesday April 23, 2014 @11:39AM (#46824811)

      Right - if we find out that these are happening much MORE often than previously thought, and yet damage is rare, then it seems like they're LESS of a risk than previously thought. Sort of like finding out that when you swim at the beach, sharks are close by more often than you realized - meaning the risk of them attacking you is lower. If anything this indicates that the Earth's natural asteroid defenses are more robust than previously realized.

      Besides, I remember reading that kiloton-scale atmospheric asteroid detonations happened once every month or two, but this indicates it's less often than that, so they're actually LESS common than I thought. I could have misremembered that stat, though.

  • The asteroid impacts detected are almost all air bursts and they have no radiation. So almost no damage is being done. A better description would be to compare it to lightning strikes, not nuclear bombs.

    It's not like we are getting city sized destruction on a regularly basis, it's like we are getting thunderstorm type events on a regularly basis.

    The real danger would be for things signifcantly larger that hit ground, rather than the upper atmosphere.

    • Impactors actually hitting the ground would definitely cause more damage. But air bursts can still be devastating enough. Tunguska was an air burst and it leveled something like 2,000 square Kilometers of forrest. Granted Tunguska was much larger than the asteroids in this report.

  • Like the US politician that was demanding 2 billion for protection from an EMP attack?

    • The tax breaks given to professional sports teams could have financed a complete space station surrounding Saturn with current technology, IMO. Stop giving billionaire gladiator owners tax breaks.
      • a complete space station surrounding Saturn

        That's a pretty big space station. Maybe start with something smaller and more practical, like a train ramp connecting to orbital ring for Earth?

        • Let's promote the installation of a 5G-capable magnetic launcher (coilgun tech) that goes up the Andes in Ecuador! A 50 mile launcher using a tube that is evacuated of most of its air could replace most or all of the first stage of rockets going to LEO, cutting the cost of launch by 2/3. The technology and project scale are in the same ballpark / order of magnitude as the LHC, and would permanently alter the economics of space development. The last time an equivalent system was thoroughly studied was in

            • Interesting, thanks. I wasn't aware of these folks, and I'm pretty sure the rest of my partners in Space Finance Group aren't either. We have run several successful Kickstarter projects, including for the National Space Society and The Liftport Group (Michael Laine of Liftport is one of the partners in SFG). We recently completed the rewrite of a business plan and 'pitch deck' for another space launch company. We are also working on equity funding mechanisms for space development, although we're not quit

              • I will add that their numbers look different from work I've seen before, and use a more ambitious methodology than I would use. They want to run the entire launch using the magnetic system. This has some serious issues that make it harder IMHO - not that I know much. I believe it would be much easier to justify, finance, and build a system that replaces most or all of the first stage, which is where about 90% of the mass and propellant is spent. Just getting to Mach 5 uses up to 90% of the required fuel

                • Yeah I can confirm they're for real, although they've been on a hiatus for a while by the looks of things. I can't imagine funding for such a project would be easy to come by nor scale models! Do drop them a line though, by what they're saying that really looks like the key to space.

          • I think that some day we will look back at those sights of huge launch vehicles inching away from their launch pads as laughably inefficient.

        • My example was in comparison to the hundreds of billions of dollars that have been given to billionaires so they would somehow not stop national sports teams from playing; which already make billions of dollars. Frankly, I'd take anything for a start. This ISS stuff is fairly pathetic compared to the things governments spend money on.
  • The pen may be mightier than the sword, but nothing is riskier than thought itself.

  • Comment removed (Score:4, Informative)

    by account_deleted ( 4530225 ) * on Wednesday April 23, 2014 @11:29AM (#46824691)
    Comment removed based on user account deletion
    • Comment removed based on user account deletion
    • Fat Man didn't do less damage because it was dropped off target, it did less damage because the geography was different - the narrow valleys that Nagasaki was built in/around limited the spread of the blast wave and sheltered much of the city from the thermal effects.

  • It seems that even though it could destroy a city every 100 years, in actual fact I has never happened in recorded history.
    I am not saying we should not keep a look out, but I am pretty sure we can go to bed and still wake up without our city being a waste land.

    • Does depend a little bit on which books you count as recorded history vs. fiction, and how you interpret the descriptions. E.g. "fire and sulphur rained from heaven" could be volcano - unless you believe the writers' culture would have known what a volcano was and would have said "from the mountain".

    • world wide recorded history is less than 500 yrs old.
      there were hardly an cities in the world until about 100 yrs ago.
      there were hardly any people in the world until about 10K yrs ago.
      http://www.prb.org/Publication... [prb.org]

    • It seems that even though it could destroy a city every 100 years, in actual fact I has never happened in recorded history.

      Sodom and Gomorrah? [universetoday.com] Also, keep in mind if this theory is accurate, this was an asteroid strike in the Alps that managed to wipe out a couple of cities in the middle east.

    • by cusco ( 717999 )

      Ubar (Iram), on the frankincense trail in the Middle East seems to have been either destroyed by or abandoned after a meteor strike in the area, possibly associated with the Wabar craters. The site is in what is generally referred to as the 'Empty Quarter'.

  • by szyzyg ( 7313 ) on Wednesday April 23, 2014 @11:47AM (#46824889)

    They're nothing to do with nuclear test monitoring, they just happened to use data from the monitoring network to count the number of kiloton scale events in the last decade or so.

    The B612 Foundation is a non profit organization trying to raise money for a asteroid discovery spacecraft, a telescope that will sit down near Venus's orbit and look outwards, enabling it to see asteroids near earth without the sun dazzling the optics (half the asteroids passing near earth are invisible because they are too close to the sun). It's not an unreasonable goal when you consider that high profile museums and educational institutions regularly raise hundreds of millions of dollars in donations.

  • by hansraj ( 458504 ) on Wednesday April 23, 2014 @11:50AM (#46824935)

    I don't think anyone is implying that we are doomed because of _these_ impacts.

    However, in general the frequency of an impact event [wikipedia.org] is inversely proportional to the size of the impacting body. Smaller impacts happen more often than the larger ones. Counting the smaller ones precisely gives you an idea of what the risk of a big event is.

    So far people underestimated these smaller ones that is being reported. The wikipedia article I linked to earlier, suggests one impact every five years at the level of 5 kT of TNT. These guys being right would imply a risk of at least a magnitude higher than previously estimated. That increases the risk for the really big ones too.

    • I'm not sure I get this.

      What I'm guessing is that the theory says that for every 1,000,000 grains of sand on the beach, there is one rock the size of your fist. There are 1,000,000,000 grains of sand, so there must be 1,000 rocks. What these guys are saying is that there are, in fact, 10,000,000,000 grains so there must be 10,000 rocks.

      If I'm drawing the analogy correctly, I'm not sure I understand how they got the relationship between grains of sand and rocks and how they know that's accurate.

  • by green is the enemy ( 3021751 ) on Wednesday April 23, 2014 @11:59AM (#46825023)
    The article authors say that most of the dangerous asteroids are already being tracked (additional tracking efforts under way), and can potentially be deflected since collisions can be predicted decades into the future. That's only a half-truth. Comets in the outer solar system are too dark to detect in their present locations, but can arrive at Earth very quickly. There will not be enough time to deflect them... Statistically, what percentage of impacts are from objects originating in the outer solar system? Is that even possible to determine?
    • Statistically, what percentage of impacts are from objects originating in the outer solar system? Is that even possible to determine?

      We don't know, and it's unlikely to be easy to determine.

      When an impactor makes it to the surface at interplanetary speeds (minimum 11km/s, typically more like 25-30km/s), the kinetic energy is sufficiently high that the overwhelming majority of the impactor is vaporized and blown back out of the crater. While this material does fall back to earth, it's very dispersed and ext

  • by EngineeringStudent ( 3003337 ) on Wednesday April 23, 2014 @12:10PM (#46825131)

    We don't have enough history to gauge what actually has happened over time, so we have to estimate.
    We approximate by finding big rocks or chemistry on earth, looking at craters on the moon, or this.

    In all these cases we are using the small but frequent to infer the distribution of big but hugely problematic events. Our best answer the question about the likelihood of a killer impact is grossly changed if this tail is changed.

    Think about it like floods. We ask how likely a 10,000 year flood is going to happen next year. We have ~100 years of rainfall data. We fit it to a distribution that is appropriate and then use those fit parameters to make a best guess. If our rain gauge was only measuring half the rain, we might under-estimate the actual risk by a factor of 10x or 20x.

    There is good correlation between "killer impacts" and location of the sun in the galaxy (yes it moves around). We are starting to enter a higher risk region (transition to edge of arm) and perhaps the fundamental distribution is changing. In that case the history of craters on the moon or other might not be meaningful indicator of the near future.

    Considering this I think good tracking is not a bad idea and should be thought out well and properly considered.

    • by cusco ( 717999 )

      When Comet Shoemaker-Levy hit Jupiter astronomers estimated that it was a once in a century to once in a millennium event. Since that time, with our improved telescopes, we've seen evidence of half a dozen more similar impacts. When astronomers started observing the Moon for impacts they expected to see a noticeable strike every couple of years, instead they're seeing a couple every year. I think that estimates of the amount of junk floating around the solar system may be radically low.

      • The problem we have estimating this stuff is that realistically we haven't really been looking. Ironically the first space facing radars looking for asteroids were only funded after the Movie Armageddon and what we've got in place right now is woefully inadequate. We'd likely only find the planet/civilization killer asteroid days or at a best a month or two before it hit earth, long after it was too late to do anything about it. We'd have a month warning to plan the end of humanity (which was IMO aptly demo

  • the whole solar system is covered with asteroid collisions..... shouldn't take a damn genius to get it's a real possibility to be hit by something a little too big to go unnoticed.... and the best solution ,as dear C.Sagan said, is to become a spacefaring race...the sooner we move our asses to mars (and beyond) the better.... it's our duty as a specie to at least colonize the solar system.... ...when they will stop laughing about it...
    • Spacefaring ought to be postponed to the 22th century or late 21st.. We have more pressing things right now, mankind has yet to learn how to feed itself without destroying the land, rivers, climates and even the oceans.
      When we'll be able to have many terawatts of clean power at home as well as decent energy storage (maybe make fuel out of water and air, or water and CO2 found in the oceans) then maybe we can dream about making shelter, food, air and water from moon or Mars materials.

      • Solar microwave power satellites would provide all the clean energy you could wish for, but need a lot more orbital infrastructure before they can be deployed.

        As for "destroying the land, rivers, climates and even the oceans", all of these remain merrily undestroyed. If you mean reducing the biodiversity around us you may have a point, but efforts are being made to preserve and protect as much as possible. Also, before we descend into a spiral of remorse a couple of points - protection of the biosphere and

      • by cusco ( 717999 )

        Yeah, because our civilization is only capable of doing one thing at a time . . .

        The impediment to feeding everyone while maintaining a viable ecosystem is not technological, it's political. Powerful people get that way and stay that way by ensuring that the overwhelming majority have nothing. The Pentagon budget for JUST LAST YEAR was larger than the inflation-adjusted cost of the entire decade of the Apollo program, and what do we have to show for all that expense? Nothing. In fact, less than nothing

  • In all of recorded human history, how many Cities, towns, villages, settlements or even individual humans have been directly killed by a meteor or asteroid impact?

    The probability of being killed by a nuclear weapon is higher. This is simply a case of NASA creating some hype to justify continued budgets for a "space" agency that can't go to space any more.

    • by dublin ( 31215 )

      Agreed. If anything, this study simply proves beyond a reasonable doubt (especially when viewed with respect to a few thousand years of recorded history) that taking any action at all to "protect the earth" from such impacts would just be a monumental waste of money. While the risk isn't zero - it's certainly close enough.

      If they want to take up a collection on Kickstarter or Indigogo, then fine, but there's no doubt that what they really want is another vacuum hose into the taxpayers' wallets to defend a

    • by cusco ( 717999 )

      NASA had nothing to do with this. Private organization. Kindly remove your head from your posterior and re-insert it into the sand.

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