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Asteroid Impacts Bigger Risk Than Thought
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."
Is the Earth basically getting nuked (in terms of explosive yield) about twice per year without anybody noticing?
The B612 Foundation 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.
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?
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.
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
"First they came for the slanderers and i said nothing."
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.
excitingthingstodo.blogspot.com
Like the US politician that was demanding 2 billion for protection from an EMP attack?
I apologize for the lack of a signature.
The pen may be mightier than the sword, but nothing is riskier than thought itself.
Little Boy clocked in at ~15 kilotons, not 45 kilotons per TFS. Fat Man was ~21kilotons, though it was dropped off target and ended up doing less damage than Little Boy.
I want peace on earth and goodwill toward man.
We are the United States Government! We don't do that sort of thing.
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.
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.
I don't think anyone is implying that we are doomed because of _these_ impacts.
However, in general the frequency of an impact event 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.
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?
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.
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...
Of course we don't notice them we're too busy looking at our smart phones.
Nuclear bombs? Asteroid impacts? Acid Rain? Toxic Waste? Concealed Weapons?
No!
Global War ^h^h^h^h^h^h^h^h CLIMATE CHANGE is what is going to kill us all and that is all the media should report.
We should stop driving our cars and shut down all our factories in order to save the planet from melting.
Escandalo!
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 heads every time, what are the odds that it will come up tails? You don't know... You can't know. You can make some educated guesses, but there is no real confidence. In the case of these explosions I'm sure they can model the size, altitude, and some other things, but still, they can't really know this, and they seem to fail to account for things like the impact of jupiter and the moon and sun on larger asteroids (which does actually affect the math). Second, you can compare the numbers to recorded history. The earth has certainly been hit by asteroids that would destroy a city. The last one probably happened off the coast of New Zealand around 1400 BC and caused a tsunami wiping out some local villages. 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.
Notice the article removed the ridiculous references implying that mega-hiroshimas happen all the time?
...hype is running out of steam. Now we'll see used meteor shield salesmen in academia looking for govt tit and power.
Yet there has never been one in recorded history.
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.
My math isn't very strong; can you explain the (1-0.3*0.03)^10 part?
You mean (1-0.3*0.03)^100? (You lost a digit.) Let's walk it:
0.3 land fraction = probability a given meteor hits over land (assuming equal likelyhood it hits any given area).
0.3 * 0.03 Multiply by the fraction of land that's urban to get the probability it hits over urban land.
1- 0.3*0.03 Convert to the probability it misses all urban land. (P(hit) + P(miss) = 1 (certainty)).
(1-0.3*0.03)^100 We get a hundred of 'em in 50 years (assuming 2000-2013 is typical). Raise to the hundredth power to get the jackpot probably that they ALL miss.
1-(1-0.3*0.03)^100 Convert to the probabiltiy that at least one doesn't miss.
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way
Orbiting body surrounded by other orbiting bodies occasionally gets smacked by an orbiting body, news at 11.
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. Computer modelling shows that this is the norm for megaton asteroid explosions, not the exception - most asteroids are rocky conglomerates that would dump their energy into massive atmospheric explosions and leave no craters, even as the fiery plasma jets from the sky lay waste to the surface of the Earth. The asteroids that form craters are megaton range iron asteroids (only ~1% of meteors are iron based on Antarctic data), or extremely large (hundreds of megaton yield) rocky ones.
Starships were meant to fly, Hands up and touch the sky - Nicky Minaj
a defense against these global extinction objects is astounding. All of mankind's focus should be on this one thing.
Good God! What a fuckin dopey thing to say.
The dinosaurs became extinct because they didn't have a space program. And if we become extinct because we don't have a space program, it'll serve us right! - Larry Niven
"Think about how stupid the average person is. Now, realise that half of them are dumber than that." - George Carlin
Ah yes, the old "I'll quote Wikipedia because it'll make me look smart" trick. Except it doesn't when you're a clueless idiot and you're quoting it to someone who does know what he's talking about.
Lame excuse to make everyone afraid and then raise the military budget so we can all sleep at night safely. We already have a Star Wars program isn't that enough...
Shit that happens every 50 million years doesn't scare me, unless you happen to live near Krakatau or something.
If you're into geological scares, you should be worried about global warming and ocean acidification which are amazingly short term. On the scale of a human life, except the politicians, members of congress or parliament, ministers or secretary of state, presidents etc. will face the problem of not peeing themselves soon and thus don't care the slightest about it.