As the US government ponders a strategy to deal with threatening asteroids, a dramatic explosion over Indonesia has underscored how blind we still are
to hurtling space rocks.
On 8 October an asteroid detonated high in the atmosphere above South Sulawesi, Indonesia, releasing about as much energy as 50,000 tons of TNT, according to a NASA estimate released on Friday. That's about three times more powerful than the atomic bomb that levelled Hiroshima, making it one of the largest asteroid explosions ever observed.
However, the blast caused no damage on the ground because of the high altitude, 15 to 20 kilometres above Earth's surface, says astronomer Peter Brown of the University of Western Ontario (UWO), Canada.
Brown and Elizabeth Silber, also of UWO, estimated the explosion energy from infrasound waves that rippled halfway around the world and were recorded by an international network of instruments that listens for nuclear explosions.
The explosion was heard by witnesses in Indonesia. Video images of the sky following the event show a dust trail characteristic of an exploding asteroid.
Sudden impact
The amount of energy released suggests the object was about 10 metres across, the researchers say. Such objects are thought to hit Earth about once per decade.
No telescope spotted the asteroid ahead of its impact. That is not surprising, given that only a tiny fraction of asteroids smaller than 100 metres across have been catalogued, says Tim Spahr, director of the Minor Planet Center in Cambridge, Massachusetts. Yet objects as small as 20 or 30 metres across may be capable of doing damage on the ground, he says.
"If you want to find the smallest objects you have to build more, larger telescopes," says Spahr. "A survey that finds all of the 20-metre objects will cost probably multiple billions of dollars."
The US Office of Science and Technology Policy, which advises the White House, must develop a policy to address the asteroid hazard by October 2010 under a deadline imposed by 2008 legislation. It is likely to be influenced by a report from the National Research Council on the asteroid problem, which is expected by year's end.
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Have your say
Use The Money To Save More Lives On Earth.
Mon Oct 26 23:21:43 GMT 2009 by Graham
http://www.theaxion.com
If an Asteroid of 20-50+ metres across happened to strike the Planet Earth in the next 50 years there is a small chance it might level a city with the loss of many lives.
However, if it is going to cost billions of dollars to spot them before they hit it can be argued that a) if spotted we might not be able to do anything about it anyway and b) the money may be better spent and save more lives curing say Malaria or Aids.
We should perhaps invest in detecting that an Asteroid hit that takes out a city was not a nuclear strike and therefore prevent an unfortunate retaliation.
The money left over can be used to extend the sky survey to ensure that mass extinction size Asteroids and Comets are discovered and technology developed to deal with them.
Hunting for all the smaller Asteroids seems to offer poor ROI and given the number out there, the chance of finding one thats coming our way is small.
True but your but your counter aurgument is in your comment realy. The best way of knowing that an asteroid is resonsible for an explosion is to have predicted its arival in advance.
I only worry that we will reach a stage where we have a system with "100%" coverage of asteroids caperble of produce a nuclear type effect. What it theres a sudden and unpredicted explosion do we then jump to the conclusion that its nuclear? If such a system is set up and relied upon for nuclear/asteroid explosion differentiation it needs to be more fail safe than a freezer at the south pole.(no climate change)
it is incredibly easy to differentiate between the two. one produces an incredible amount of radiation in the surrounding area and one does not. and since each nuclear weapon produces a distinct radiation signature you could never get a asteroid and a nuclear bomb mixed up
Simple. If a city leveling explosion occurs WITHOUT prior tracking of an ICBM/IRBM boost phase (that rather robust capability exists now), then it was either an asteroid, OR...someone detonated a nuclear device they had slipped into the city.
Use The Money To Save More Lives On Earth.
Tue Oct 27 21:11:09 GMT 2009 by Dennis
http://freetubetv.net
There's still that possibility that it will miss impact. It's happened before and it'll happen again.
The difference is clear: asteroids are hardly nuclear!
I agree we should not waste money trying to find asteroids that might hit earth, but go one step further - no matter small or big.
However I don't agree we should spend money on saving lives (I am assuming you are talking about Homo sapien lives).
Every life is destined to end. At the present moment in time, our numbers are the greatest threat to our existence. Besides our numbers are the cause of the mass extinction of thousands of equally relevant species.
A better idea would be shutting down all medical facilities till we have a sustainable population. Use the money to educate the masses.
@scientific earthling;
You have obviously never experienced the suffering and loss of a friend or family member due to illness. A more humane suggestion (regarding overpopulation) would be to encourage people to have no more than 2 children.
Too bad encouraging people to limit their childbearing will never happen. Overpopulation is the elephant in the room, but also a "third-rail" issue for politicians. Corporate profits depend on a "growing" economy that includes more and more consumers. In addition, some religions even frown upon birth control and others believe that since Jesus is coming soon, there is no sense worrying about overpopulation or preserving natural resources for future generations. And fewer and fewer people seem to have any personal connection with nature apart from using it as a recreational playground.
Nothing wrong with death; we've all got to go sometime. I vote for going by asteroid! Although a deadly disease specific to humans might be more pleasant for the nonhumans.
Well, of course none of us will have much control over asteroids or diseases, but overpopulation sounds like the most miserable future of all to me. We CAN do something about it, but people are animals and very selfish when it comes to passing on their genes.
P.S. I never had children, so I'm doing my part ;)
That, was the most mind numbingly stupid comment i have ever heard on NS.
If a 6 mile asteroid slams into the earth 90% of ALL life will die. Homo sapiens will be the most able to survive of the higher life forms.
We will adapt and come back again.
You will probably die so you wont care. So forget you i have always had a thing about letting billions of people die.
Ok here is a idea all those who think we have population problem so bad it means becoming Nazies to fix it do this. Suicide!! really leave this horrible world and if you have kids? THEM to!!!
Oh wait YOUR not supposed to be the problem are you its always some other guy.
Idiots.
I actually support his comment in some ways. Medicine isn't always a good thing... It seems obvious to me that we already live too long.
Who said anything about a 6 mile asteroid? The original poster mentioned a 50 METRE asteroid.
@scientific earthling:
"A better idea would be shutting down all medical facilities till we have a sustainable population"
That is not likely to result in a population decrease, only in a great increase of misery. People in uncertain circumstances breed more to compensate. The best way to stabilise population levels, other than legally limiting the number of children allowed, is to provide decent health care and family planning. Why do you think the countries with the fastest growing populations are also the ones with the worst living standards and health care? In Europe, horrid plagues have decimated ancient populations over and over again. That did not prevent population numbers from rebounding every time and keep on increasing, right up to the coming of modern medicine and improved sanitary conditions.
Hitler and Stalin would approve ...
Use The Money To Save More Lives On Earth.
Tue Oct 27 12:49:28 GMT 2009 by Lenny
http://www.gwmarketing.co.uk
True that our population at this current time poses a serious problem, but who is to say that the only way to cure this is through reduction in numbers?
At the moment our numbers as we all know are seriously hurting the planet, but that's not down to the numbers themselves - but instead the massive resources we are taking to sustain those numbers.
If we begin by focusing on and then succeeding in creating a clean energy source as an alternative to culling millions as Mr scientific earthling's suggestion, and then furthermore the wisdom to share it openly, the pressure on our natural environment will fall dramatically.
I would call that a good first step.
Everything we need to succeed as a race is right here on earth - like a puzzle we have to piece together the clues. Sadly, it's a puzzle played against a clock powered by our own stupidity and self imposed ignorance... with that in mind, i think its going to be a really close finish. - but finish we will :)
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Use The Money To Save More Lives On Earth.
Tue Oct 27 03:23:25 GMT 2009 by Graham
http://www.theaxion.com
To add...I would like to see some serious attempts at risk analysis before commitiing billions of dollars to search for these small asteroids. For example, the earth is 2/3rds ocean, and much of the land area is uninhabited. What is the probability of an asteroid hitting and penetrating the atmosphere directly above a major city and how many would die?
If it is less than the probability and death rate of; Nuclear War, A deadly pandemic, Malaria, Aids, Cancer, Obesity, Global warming, starvation etc...that is, events that we can have some influence over here on Earth if we spend the right amount of money then we should not spend the money on looking for these types of Asteroids and spend the money where it will have the greatest effect.
I agree that perhaps over population may be a problem in the future and controlling birth rates and perhaps even voluntary euthanasia (I am not a Nazi, I said voluntary) may be considered but we should try to eliminate suffering and unnecessary death where we can.
A small asteroid strike, like volcanoes and earthquakes, is one of the many risks of life, akin to driving a car but less of a risk, and not really easily controlled by humans so we shouldnt get hung up on it like we have with the tiny threat from terrorism on which many billions has been spent/wasted.
There's one thing wrong with your argument: an asteroid hitting the water is far worse than one hitting land. If an asteroid hits an ocean, it will cause large waves that will go far further than shockwaves through land, and will be far more destructive.
Risk analysis is still somewhat impossible simply because we don't have enough information. It's somewhat like playing Russian Roullette without knowing how many bullets are in the gun.
I don't disagree with any of your points that there are other perfectly valid threats to focus on or that they may be a more efficient use of money. Few others, though, can cause extinction at the speed that an asteroid strike could. One asteroid is all it takes to end all complex life on Earth. It'd be a real bummer to cure all disease, stop all war, and fix global warming only to be wiped out the next day by an asteroid that we didn't even see coming. We have to focus on all threats as evenly as we can until we know for sure how to fix one before focusing on or excluding it.
"There's one thing wrong with your argument: an asteroid hitting the water is far worse than one hitting land. If an asteroid hits an ocean, it will cause large waves that will go far further than shockwaves through land, and will be far more destructive."
Not if the asteroid is only 50M across and detonates in the air above the ocean.
@ Graham,
"To add...I would like to see some serious attempts at risk analysis before commitiing billions of dollars to search for these small asteroids. For example, the earth is 2/3rds ocean, and much of the land area is uninhabited."
Mate, that asteroid was only 10 metres across, if it was twenty and it hit land, somewhere in your country... There's your risk analysis right in your face
Use The Money To Save More Lives On Earth.
Tue Oct 27 12:40:02 GMT 2009 by Graham
http://www.theaxion.com
I think that there have been models done of asteroid impacts on water and the doomsday scenario of a massive Tsunami and these show that unless the impact is in shallow coastal water then the Tsunami would not be that dangerous. The article is in New Scientists Archive somewhere, if you have access to that look it up. Again I would like to know the probability of a 50 metre asteroid hitting a coastal area occurring given the size of the oceans of the Earth.
To answer the other point about an asteroid falling on my town, I think the probability is small. To put things into perspective, what do you think is the probability of say a 50 metre wide asteroid hitting directly over the Islands of Hawaii in the middle of the Pacific ocean? Look at a globe of the Earth (or Google Earth) and make a guess.
I think that anything larger than 50 meters should be looked for aggressively so I am not suggesting to stop looking for Asteroids that could threaten all life on earth, only I dont think its worth spending billions looking for small ones.
Now multiply your little town by all the umpteen hundred thousand little towns all over the world, you selfish maroon!
How about a 50 metre asteroid over Hawaii and California and Florida and New York and North America) and New South Wales and Kenya and Belgium and Switzerland (well,probably most of Europe) and India and (speaking of shallow seas) anywhere in the Australasian archipelago sometime in the next 200 years or so?
Gotta get the scale of these things in perspective, you know...
You speak of probabilities of disaster from asteroids or nuclear war. I basically agree with you about the small chance of something that probably won't hurt many people anyway. But just because something is not highly probable doesn't mean it shouldn't be prepared for.
There's a very low chance of a fire at my residence or place of work. Should we then not have fire departments? Or have only one fire truck in each city?
Long-range goals of accurately predicting where an asteriod will hit will be useful so that people may evacuate. Eventually knocking out a deadly asteroid before it hits would be desirable.
this must be the most poorest collection of comments I viewed on new scientist, I'm not saying every comment is ridiculous and inhuman. but first of all saving money to saves lives?? economies spend large budgets and resources on killing there own brothers/sisters/children/family ! i.e. war machine, looking up and checking whats going to fall on your head is less sensible then spending billions on war games? the citizens in this world need to get bloody real for once in its GOD damn history and if anyone dares to comment that we don't end up killing ourselves/family by being at war with eachother may GOD send a 100 talent weight fireball on your head moronic human
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Use The Money To Save More Lives On Earth.
Wed Oct 28 22:13:47 GMT 2009 by BobVADemHAwk
http://www.democrats.org
Tell that to the realtives of the city inhabitants you just saw destroyed in your hypothesis here. This aritcle reveals why we need a drastic increase in NASA funding to support programs and R&D; into finding ways to keep track of everything larger than 5m in diameter. Furthermore, AIDS and Malaria will be completely irrelevant if we miss the proverbial big one coming in.
This comment breached our terms of use and has been removed.
So why does it have to be one or the other--build a system to detect smaller incoming asteroids or health care? The fact is, money is already being spent on both, and that will continue. The money being spent on one has no affect on the money spent on the other.
And all you 'population bomb' fear mongers, why do you never practice what you preach? YOU refuse medical care for yourself. YOU die young to save the planet. YOU sterilize yourself so you have no kids. Why don't they? For the same reason terrorists never strap bombs to themselves, but only on the fools they control.
You love yourselves when you buy a hybrid or those stupid mercury-filled light bulbs. You buy carbon offsets so you can fly all over the world guilt free. Carbon offsets are just a modern day papal indulgence, allowing the user to get into tree hugger heaven.
As for me, my big cars and I are fighting hard to stave off the coming ice age.
You could not see it
But you heared its impact
in the atmosphere...
Could you "hear" asteroid turbulence
int he heliosphere?
Perhaps from somewhere
in the shadow of the earth?
Disturbances in the ionosfere
surely are generating enough traces...
OK, this is getting ridiculous.
1) No country, or combination thereof, is in a position to combat the solor system entirely.
We will have to pick and choose our battles.
2) "The White House must develop a policy to address the asteroid hazard by October 2010 under a deadline imposed by Congress"
OK, no problem with the premis...but how far will we all "demand" that these "acts of God" (if you will) be mitigated, spare no expense, by the government?
Hopefully we can all, collectively, keep an eye on where, and on what, we are spending our money.
Government will do, perhaps unfortunatelly at times, whatever we demand of it. This ensures our freedom, but also curses us all to our own desires.
I notice a few asteroid blast recently, Indonesia, Canada, Sudan, and may be Latvian. So, may be a big one is on its way here?
"weesallgonnadiee!"
the more asteroids you detect the greater the panic and so9on all the population will run around like headless chickens
I believe, in government contexts, that would be considered a feature rather than a bug.
SteveinTX
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