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How We Knew AL00667 Would Miss Earth

timothy posted more than 10 years ago | from the we-already-saw-that-movie dept.

Space 290

jefu writes "In January there seems to have been an incident in which it was thought that an object (asteroid) in space might have hit the earth within a couple of days of being spotted. It did miss, though. This story (from NASA/Ames) talks about the discovery of the object and the process that astronomers went through to determine if the asteroid was or was not a threat."

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fp (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8371757)

fp

Fuck "we" (-1)

Adolf Hitroll (562418) | more than 10 years ago | (#8371861)

II do not like the sensational way the headline is written, this is a poor attempt at being interesting and only desserve a (-1 cretinus simplex tacosnottibus)moderation !

Now, watch the Passion and save your soul : if Gott wanted us to be morons he'd have made us kipa-heads or towelheads.

OMFG I got a FROSTY PISS! (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8371758)

Dudes, GNAA is teh suxx0r! Ghey boyz!

Re:OMFG I got a FROSTY PISS! (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8371799)

j00 f4173d the frist ps0t, d00d...

Wow (3, Insightful)

rholliday (754515) | more than 10 years ago | (#8371761)

I'm glad they're so confident. I, for one, find the thought terrifying. :)

Too bad they already made the (17 versions of) the movie about this. It's a nice story.

Re:Wow (5, Funny)

asbestos_tophat (720099) | more than 10 years ago | (#8371890)

The earth is hit by material every day. A planet killer meteor hits about once every... Wait! We are still here? hmmm, that must mean what?...

Besides everyone knows the world ends in 2017 due to old UNIX Y2K17 bug & embedded NT licence key expiry causing cascade failure of ICBM guidance systems. ;-) lol I will need Lead underpants soon... ha ha ha

Relax, Statically speaking you will probably win the lotto 12 times, get struck by lighting 302 times, and die from stress or cancer 240 million times... likely to happen long before then... ;-)

Re:Wow (3, Insightful)

Anonymous Coward | more than 10 years ago | (#8371980)

Wouldn't it be a bit difficult for me to die of cancer 240 million times? I can understand once but...

timing... (5, Funny)

menn0nite (699138) | more than 10 years ago | (#8371765)

perhaps AL00667 creates MADMEN [slashdot.org]

Flipped a coin? (1, Insightful)

ObviousGuy (578567) | more than 10 years ago | (#8371767)

Even if it was discovered that an asteroid were bound for earth, I don't think we've got any better idea than shooting a ragtag band of oil drillers up to the meteor to blow it up.

We probably could have had something in place to shoot such a threat down if we had fully funded the Star Wars MDS project, but sadly geopolitics killed that project.

It might be time to start thinking realistically about ways to deflect asteroids from Earth impact instead of relying on 'we worked it out using computer simulation' assurances.

Re:Flipped a coin? (5, Informative)

el-spectre (668104) | more than 10 years ago | (#8371809)

Most all missle defense proposals depend on punching a hole in an ICBM by heating it. For all their destructive potential, ICBMs are 90% thin skinned gas tank. You could take one out with a grenade, if you could somehow get it there.

The power required to destroy any rock big enough to survive atmospheric entry would be orders of magnitude greater.

Re:Flipped a coin? (2, Interesting)

ssbljk (450611) | more than 10 years ago | (#8371856)

what are requirements for such a rock to survive its way through atmosphere? I doubt that size is only thing that matters. material shoul'd be counted too.

Re:Flipped a coin? (4, Interesting)

el-spectre (668104) | more than 10 years ago | (#8371939)

true. Composition matters a lot too. For a given size, a "stony" or primarily rock asteroid will burn quite a bit more than it's "iron", or mostly metal counterpart.

Also, stony asteroids tend to explode if/when they reach the lower atmosphere. Comets, which are primarily ice and stone, are very unlikely (but not impossible - see tunguska) to survive entry.

Any of these are much stronger than an ICBM, of course.

Re:Flipped a coin? (2, Funny)

Anonymous Coward | more than 10 years ago | (#8372173)

see tunguska??

Tunguska was Tesla, MAN! wake up and smell the ozone

they never found not one drop of evidence of foreign matter in soilcores from all the expeditions back there since. It was Tesla testing his death ray, i'm convinced

Re:Flipped a coin? (0)

BJH (11355) | more than 10 years ago | (#8371953)

If it's moving fast enough, the atmosphere doesn't mean shit - it'll punch through that quickly enough that air friction doesn't have time to reduce its size.

Re:Flipped a coin? (1)

yevelse (686791) | more than 10 years ago | (#8372109)

Unfortunately, you are mistaken. The kinetic energy from friction will blow it apart (big asteroids are not composed from stone only, but mainly from ice-stone mixture)

Re:Flipped a coin? (1, Funny)

Anonymous Coward | more than 10 years ago | (#8371976)

That's like asking- What's heavier a ton of feathers or a ton of lead? There's an asteroid the size of Texas heading your way. Don't worry it's made from pocket fluff.

Re:Flipped a coin? (0)

NeoThermic (732100) | more than 10 years ago | (#8371973)

>> Most all missle defense proposals depend on punching a hole in an ICBM by heating it.

And how do you think they were planning on doing that? Using a hairdryer?

The original idea was to use an electron gun. You see, the basic priciple of any weapon is transfering energy, and if you get enough of it at a point, it does damage. Intrestingly enough, so would a stream of electrons.

However, to use an electron gun, you have to have a vaccume. If the ICBM was launched, but didn't go out of the atmosphere, then it couldn't be hit.

In theory, if we had this electron gun in space, we could aim it at our astroid that might hit us; we should in theory be able to give it enough energy to move it off course at best, break it into something far less dangerous at worse.

NeoThermic

Re:Flipped a coin? (0)

Anonymous Coward | more than 10 years ago | (#8372025)

If the ICBM was launched, but didn't go out of the atmosphere, then it couldn't be hit.
If it didn't go out of the atmosphere, it either wouldn't be "inter-continental", or it wouldn't be "ballistic". Duh.
In theory, if we had this electron gun in space, we could aim it at our astroid that might hit us; we should in theory be able to give it enough energy to move it off course at best, break it into something far less dangerous at worse.
At worst, it would do ABSOLUTELY NOTHING, and the asteroid would still hit. But you keep on dreaming!

Re:Flipped a coin? (3, Insightful)

October_30th (531777) | more than 10 years ago | (#8372028)

break it into something far less dangerous at worse.

So instead of one huge target you could in principle land on, you'd get a swarm of smaller but still deadly rocks that would rain devastation on Earth?

No, the only permanent solution to the extinction level event problem is to get some of us off this goddamn planet.

Re:Flipped a coin? (3, Interesting)

mikerich (120257) | more than 10 years ago | (#8372436)

Most all missle defense proposals depend on punching a hole in an ICBM by heating it. For all their destructive potential, ICBMs are 90% thin skinned gas tank. You could take one out with a grenade, if you could somehow get it there.

Only the older American missiles which used their outer wall as the skin of the fuel tank. It saved on weight and gave them formidable acceleration. The Soviets always used separate tanks and a thick steel skin - largely because they never worked out how to build precision skins. Both of which gave their missiles a massive strength.

Both countries now use solid fuelled boosters which are much tougher.

And as for a grenade - why bother - you can use a wrench [k12.ar.us] .

Best wishes,
Mike.

Re:Flipped a coin? (3, Insightful)

Drakin (415182) | more than 10 years ago | (#8371829)

Um, the problem with that is the whole concept is to be dealing with targets launched from earth, at earth based targets.

Meaning they'd be pointing in the wrong direction.

Re:Flipped a coin? (3, Interesting)

Izmunuti (461052) | more than 10 years ago | (#8372000)

"We probably could have had something in place to shoot such a threat down if we had fully funded the Star Wars MDS project, but sadly geopolitics killed that project."

Doubtful. Weapons for bringing down delicate ICBMs -- even if they had surprised everyone and actually worked -- would be useless against a mountain of rock and ice moving at kilometers per second.

It would be like flicking peas at the Exxon Valdez.

To deal with large objects on a collision course we first need a few decades of warning. Given time, a little nudge can make a big difference. For a rock kilometers in diameter, even thermonuclear explosions count as nudges. If we only have a few months of warning; we're well and truly screwed.

Iz

Re:Flipped a coin? (2, Insightful)

Anonymous Coward | more than 10 years ago | (#8372010)

you wouldn't want to destroy such a beast. several pieces of rock flying towards earth are after all even more dangerous than one big stone -- even if the big rock would be way bigger than the small ones :-)

what you would want to do is attaching some kind of nuclear device to it, which melts away pieces of its surface and with the gas and pressure created it slowly pushes the meteor (or comet) in another direction.

it would be like pushing a huge ship away with your hands, whilte it is just floating in the water: probably slow, but it would definitely work. there's no (relevant) opposing force in space :-)

Miss Earth what? (5, Funny)

Joe Enduser (527199) | more than 10 years ago | (#8371769)

Re:Miss Earth what? (5, Funny)

richie2000 (159732) | more than 10 years ago | (#8371786)

If you're gonna do it, do it right [wikipedia.org] . :-)

Interesting... (5, Insightful)

Spazmasta (744225) | more than 10 years ago | (#8371771)

that most people didn't hear about the asteroid until long after the near-miss was over. Seems to bring up the old argument of whether it'd be better to inform the public and try to do something about it or keep it under wraps and possibly die in blissful ignorance...

Re:Interesting... (5, Funny)

qkw (755948) | more than 10 years ago | (#8371781)

better yet, send bruce willis up there, and don't tell anyone. That way he might get some money for it if it works and he returns, or we all die, or (the optimal solution) he diverts the asteroid and goes hurtling off into space with it..

Re:Interesting... (5, Insightful)

retards (320893) | more than 10 years ago | (#8371844)

Well, yes, I guess you will die blissfully if you happen to be very near impact. Otherwise you can look forward to drowning in a tsunami, starving in the coming 5-year winter or just die at the looting of the local convenience store once the news breaks (duh, saltwater rain, 4 weeks of darkness, complete failure of all infrastructure, etc.).

It is a totally futile to even discuss what should be done if we are going to get hit, since there is nothing we can do about it at the moment. If the death of 80% of the worlds population and the fall of all governments is nigh, it hardly matters how people die or how the governmenst fall. It only confuses the real issue: how the hell are we going to fund a global defense system instead of funding luxury for 10% of the planet.

Re:Interesting... (-1, Flamebait)

Anonymous Coward | more than 10 years ago | (#8371948)

If the death of 80% of the worlds population and the fall of all governments is nigh
Isn't this the stated policy of the Libertarian party?

At least we'll have the Internet (5, Funny)

midg3t (724635) | more than 10 years ago | (#8372098)

Slashdotters can continue to sleep comfortably with the knowledge that TCP/IP is designed to withstand such an event; lets just hope there's a backup of the /. backend in case its server(s) get struck, shorted by the tsunami, or looted by the local villagers.

Re:Interesting... (1)

AgBullet (624575) | more than 10 years ago | (#8372353)

Well, yes, I guess you will die blissfully if you happen to be very near impact. Otherwise you can look forward to drowning in a tsunami, starving in the coming 5-year winter or just die at the looting of the local convenience store once the news breaks (duh, saltwater rain, 4 weeks of darkness, complete failure of all infrastructure, etc.). well, not all is lost. ARPANET, which later became the Internet was built to withstand anything short of armageddon remember? Saltwater rain? Pah. At least I'll still have my Slashdot. And Fark.

Re:Interesting... (4, Funny)

Hektor_Troy (262592) | more than 10 years ago | (#8372070)

most people didn't hear about the asteroid until long after the near-miss was over
Near miss? What kind of fubar misuse of a word is that? It's a near-hit.

A collision is a near-miss.

*boom* Look. They nearly missed

Appologies to George Carlin :-)

Re:Interesting... (3, Interesting)

pkaral (104322) | more than 10 years ago | (#8372212)

that most people didn't hear about the asteroid until long after the near-miss was over. Seems to bring up the old argument of whether it'd be better to inform the public and try to do something about it or keep it under wraps and possibly die in blissful ignorance...

Using utilitarian calculations, you can actually compute whether or not the expected consequences of informing are preferable to the expected consequences of secrecy. It would go something like:

Inform if EU(i) > EU(s)
where
EU(i) = p(h) * (1 - p(prev)) * U(knowing)
EU(s) = (1 - p(h)) * U(nondisr)

where
EU(i), EU(s) are the expected utility functions of informing and keeping secret, respectively
p(h) is the probability of a hit
p(prev) is the probability that a hit could be prevented if known to the public
U(knowing) is the value people would place on knowing in advance if they were going to be dead tomorrow
U(nondisr) is the value people would place on the avoided distruption of a global panic (the economic + emotional "costs" saved)

Thus, whether to inform depends on:
- How certain are you that the asteroid will hit?
- How big do you think the disruption will be if word of potential impact spreads?
- Is there anything you can do, given that it is going to hit?

I think the first one is really important. It has repeatedly been shown in research that people do not react rationally to probabilistic information. Thus, telling the public that "there is a chance that an asteroid could hit us", even when qualified by a quantification of the probability to the best of our knowledge, could actually lead to a greater mis-assessment of the risk than if nothing were said of it.

This is, of course, not a question of probabilistic and utilitarian calculations. There is a "right to information" aspect to it, as well. A good formulation would be "where is the borderline between 'creating unneccesary panic' and 'respecting people's right to know'". I would say that if the expert is worried to the point of personally taking significant action based on the information, such as buying emergency supplies etc., then he should inform the general public.

Ob Simpsons quotes (4, Funny)

IntelliTubbie (29947) | more than 10 years ago | (#8371774)

So many to choose, since it was an entire episode, but this one seems appropriate:

Sounds like the doomsday whistle! Ain't been blown for nigh onto three years.

Cheers,
IT

Re:Ob Simpsons quotes (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8371798)

in soviet russia, karma whores YOU!!

Re:Ob Simpsons quotes (1)

DJPenguin (17736) | more than 10 years ago | (#8371958)

You missed the punchline! ... "there's trouble a'brewin..." !

Re:Ob Simpsons quotes (3, Funny)

LuckyPhil (549767) | more than 10 years ago | (#8372234)

Another one

"Quick, lets burn down the observatory so that this never happens again!"

MADMEN (2, Funny)

termos (634980) | more than 10 years ago | (#8371785)

Where is my MADMEN when i need one?

Well, we were lucky this once... (3, Funny)

arvindn (542080) | more than 10 years ago | (#8371788)

...but its practically certain we're going to be hit by an asteroid real soon.

Else we'd be meeting all the time travelers from the future :)

Not so.. (0, Offtopic)

glassesmonkey (684291) | more than 10 years ago | (#8372026)

It only means that no one has invented a time-travel machine YET.. The way I understand it, IF it is at all possible then you wouldn't be able to be back in time BEFORE the creation of the time-travel machine / worm-hole / space-time effect / quantum-parallel universe traversal.

Re:Not so.. (1)

Tony Hoyle (11698) | more than 10 years ago | (#8372197)

Why not? Pretty crappy time travel machine if it was artificially limited like that...

How would you know you'd invented it? It wouldn't work unless you waited a couple of years....

Re:Not so.. (1, Funny)

Anonymous Coward | more than 10 years ago | (#8372312)

Maybe the time travelers from the future are already here.. but when the realize they have traveled back to a time when time machines aren't even invented yet, they are so embarrassed with their stupidity that they just don't talk about it.

I was lucky once.... (1)

gmby (205626) | more than 10 years ago | (#8372169)

I meet a guy on the street once,

said he was from the future;

shared his wine with me, he did.

His Delorian someone stole, they did.

his future they did steal too.

his past I give to you.

pfft (-1, Offtopic)

Graspee_Leemoor (302316) | more than 10 years ago | (#8371789)

Asteroids, Smashteroids. Who cares anymore?

Anyway, what's this I hear about a new Euro coin with the multi-view effect? I always wondered how they made those...

graspee

Re:pfft (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8371839)

That would the Dutch coin in celebration of the birth of a princess last year. It's for sale in the Netherlands since yesterday, and looks pretty cool.

Here's the scoop on it:

http://www.geboortemunt.nl/Pages/geboortemunt.ht m

Don't suppose you can make much of the Dutch language though.

Re:pfft (-1, Flamebait)

Anonymous Coward | more than 10 years ago | (#8371897)

Don't suppose you can make much of the Dutch language though.

I can't make much of the Dutch people, let alone their language. They're all perverted potheads, anyhow.

Re:pfft (0, Offtopic)

October_30th (531777) | more than 10 years ago | (#8372043)

They're all perverted potheads, anyhow.

You say that as if there's something wrong with being a perverted pothead...

DARN... (-1, Offtopic)

-Maurice66- (728513) | more than 10 years ago | (#8371790)

Bush missed another chance to test his old ballistic rocketry...

8 Comments so far - server has already timed out. (-1, Offtopic)

inertialmatrix (675777) | more than 10 years ago | (#8371791)

p00f.

Re:8 Comments so far - server has already timed ou (4, Funny)

cpghost (719344) | more than 10 years ago | (#8371821)

NASA Server hit by slashdot asteroid. They didn't see it coming...

Re:8 Comments so far - server has already timed ou (2, Funny)

BlueTrin (683373) | more than 10 years ago | (#8371991)

Nah they just have been hit by an asteroid, and you will be crushed by the waves in some minutes. =)

Within a couple of days!? (2, Insightful)

LuckyStarr (12445) | more than 10 years ago | (#8371792)

No problem! ... Bruce Willis will bust us out! ... Our super-geniuses will come up with a 5min to deadline plan and blast this bugger to pieces! ... It won't hit us anyway, because it did not hit us up to today.

Tell me Mr.Politician, what is more important: Survival of mankind or playing the powermonger game with your politician-buddys?

I say, if politicians (which are by the way trusted with OUR FATE!) behave like they do today they are gambling with the chance of survival for the entire human race. This should be considered a crime and prosecuted accordingly.

Re:Within a couple of days!? (0)

Jackdaw Rookery (696327) | more than 10 years ago | (#8371852)

"they are gambling with the chance of survival for the entire human race. This should be considered a crime and prosecuted accordingly"

This is a part of what politicians do, and yes it is wrong as they are not accountable; due to there actions not having an immediate consequence. Look at the Kyoto treaty for example, Polls in America showed support for it http://www.oneworld.org/ips2/nov98/04.32_008.html and Bush still refused to sign up.

The reason? Dollars of course. Money is more important than human survival isn't it? No? Ah.

http://www.google.co.uk/search?q=cache:QxBCWZllL Wg J:www.greenpeace.org/~climate/climatecountdown/doc uments/corporate_america.pdf+kyoto+treaty+%2Bameri ca&hl=en&ie=UTF-8

Re:Within a couple of days!? (5, Funny)

Max von H. (19283) | more than 10 years ago | (#8371858)

Tell me Mr.Politician, what is more important: Survival of mankind or playing the powermonger game with your politician-buddys?

If the asteroid were a political party, you'd find a great deal of people supporting any effort at crushing it.

I think it's time to label asteroids as "liberal" or "terrorist" to get things moving ;)

Re:Within a couple of days!? (0)

ssbljk (450611) | more than 10 years ago | (#8372035)

yeah, donate funds for my antiasteroid fondation!

Re:Within a couple of days!? (-1, Troll)

gl4ss (559668) | more than 10 years ago | (#8371859)

you know, it is largely up to faith that if we even can alter anything.

which makes it sort of parallel with making sacrifices to the ancient gods just in case if that was necessary for the survival of the entire human race(hell, they might exist you know, and allah too). heck, some people have more faith in that equivalent of that should be done rather than planning up things to save us from perils of the space.

yeah well, doing some tech to deflect some asteroids would probably advance the tech enough to be worth it. but so was building several of the monuments of the ancients.

that powermonger game btw is the collaborative decision making process of your nation, like it or not(and not everyone would deem it necessary to take drastic slashes on budget to guard against something that seems unlikely).

What's worse: (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8371793)

An asteroid hitting Earth or web design like this? [geocities.org]

Re:What's worse: (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8371807)

An asteroid hitting Earth or web design like this?

I counter with this atrocious web design [gnu.org] .

mod 04 (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8371796)

Re:mod 04 (-1, Offtopic)

Anonymous Coward | more than 10 years ago | (#8371814)

what about an asteroid hitting the earth? is it good, or is it whack?

Re:mod 04 (-1, Flamebait)

Anonymous Coward | more than 10 years ago | (#8371822)

what about an asteroid hitting the earth? is it good, or is it whack?

If it hits the Slashdot compound, it's good.

Re:mod 04 (0)

Anonymous Coward | more than 10 years ago | (#8372002)

If it hits the Slashdot compound, it's good.

And if it hits the campus of Troll Academy, the universe will rejoice in all it's splendor! 2 cars in every garage and free beer!!!

Ooooh...a chainsaw and a troll. Is it good or is it ... chop, chop?

It would mean the end of life as we know it ? (5, Funny)

Gopal.V (532678) | more than 10 years ago | (#8371804)

Onlooker1: It would mean the end of life as we know it ?
Scientist: No, but it might burn up a few cities and destory 70% of the humans ... but we don't really see a threat to the human species.
Onlooker2: So I'd be dead ?
Scientist: But the people left alive will have an excellent chance of survival due to the systematic culling of slashdot trolls .... not to mention rabid money hungry CEO types... along with a few cities as collateral damage.
Onlooker1: Why did you keep it under the wraps ?
Scientist: We were kinda hoping it would slag Sanford Wallace in location... and have the Pope claim it was divine intervention
Onlooker3: What about SCO ?
Scientist: Looks like the next one from Kuiper belt would do that clean

PS: maybe you should read "God's Debris" to be frightened by Slashdot.

How they really figured out that it was ok (4, Funny)

Aceticon (140883) | more than 10 years ago | (#8371806)

After buying a milion cans of baked beans, a zillion beer cans and 10 years worth of Playboy magazines (only for historical purposes, of course) they waited it out for a couple of days in an underground bunker.

Since they didn't felt any shake, it was proven that the meteorite had missed the Earth.

It was further proven that a zillion cans of beer barely lasts a couple of days and that having a million cans of baked beans is pretty useless when you forgot to bring a can-opener

One thing of note is that somehow, 10 years worth of Playboy magazines disapeared without a trace.

Re:How they really figured out that it was ok (0, Funny)

Anonymous Coward | more than 10 years ago | (#8371867)


It was further proven that a zillion cans of beer barely lasts a couple of days and that having a million cans of baked beans is pretty useless when you forgot to bring a can-opener


If they had had a can-opener, they would've found out how vital a good ventilation system is when eating so many baked beans :)

Re:How they really figured out that it was ok (5, Funny)

LuckyPhil (549767) | more than 10 years ago | (#8372282)

It was further proven that a zillion cans of beer barely lasts a couple of days and that having a million cans of baked beans is pretty useless when you forgot to bring a can-opener

Hmm.. lets see. Your in an underground bunker, sealed from the outside world, with nothing to eat but baked beans and beer. If that isn't a recepie for a WMD gas attack then I don't know what is!

Server Unresponsive, Article Text (5, Informative)

Anonymous Coward | more than 10 years ago | (#8371818)

Short Warning Times

Back to Archive
Article Posted: February 19, 2004

By: David Morrison

For the story of AL00667, which briefly masqueraded as an asteroid that would hit the Earth within two days of its discovery, read on.

February 19, 2004 Short Warning Times

Following is information on the small asteroid known last January 13-14 as AL00667. A preliminary analysis of the discovery data for this object yielded a possible impact with Earth in less than 2 days time -- a situation not encountered previously in the Spaceguard Program. Although we knew at the time that such a prediction of imminent impact was improbable, a collision could not be ruled out. And if a possibility of an impact in 2 days existed, what should we do about notifying governments or the public? The story of this situation on January 13, 2004, is included as part of a paper by Clark Chapman (Southwest Research Institute) presented on February 22 at the Planetary Defense conference of the AIAA (American Institute of Aeronautics and Astronautics). Several paragraphs taken from this paper are reproduced below. Following these quotes from Chapman's paper are additional quotes from a letter Brian Marsden (Minor Planet Center) wrote to CCNet on 14 January on the same subject. Finally, there is a statement posted on the website of the IAU (International Astronomical Union) discussing what lessons we should draw from the story of AL00667, and how such a situation might be better handled in the future.

Asteroids never cease to surprise us. We may never encounter a situation just like this again, but we are fairly sure to have other crises as the rate of discovery of NEAs continues to increase.

David Morrison

FROM CLARK CHAPMAN'S AIAA PAPER "NEO IMPACT SCENARIOS"

presented February 22, 2004

"Just last month (January 2004) perhaps the most surprising impact prediction ever came and went, this time out of the view of the round-the-clock news media. It illustrates how an impact prediction came very close to having major repercussions, even though -- with hindsight -- nothing was ever, in reality, threatening to impact. It is a story of success in that the impact prediction was nullified in record time, less than half-a-day, but the success was accomplished through a set of ad hoc, unofficial, and often unfunded activities and relationships, although assisted in major ways by the official infrastructure, such as it exists (the LINEAR Project, the IAU Minor Planet Center, and the NASA NEO Program Office).

"About 36 hours before President Bush's planned speech at NASA Headquarters on future American space policy, the Lincoln Near Earth Asteroid Research (LINEAR) observatories in New Mexico routinely recorded four images of a moving object. Half a day later, on Tuesday, January 13th, these data were sent (as part of the daily submission of data) to the Minor Planet Center in Cambridge, Massachusetts. Just before going to dinner, MPC research Tim Spahr ran the data through standard software to generate a nominal ephemeris for the new object. These are posted on the publicly accessible NEO Confirmation Page (NEOCP) so that amateur and professional asteroid astronomers around the world might be able to follow up on the LINEAR observations that night. It is through such follow-up astrometry that NEO orbits can be refined so that the object is not permanently lost. Spahr posted the ephemeris, based on LINEAR's four detections, on the NEOCP under the designation AL00667, along with ephemerides for several other recommended targets. Less than an hour later, a European amateur astronomer, Reiner Stoss, went to the NEOCP and noticed a curiosity: AL00667 was predicted to get 40 times brighter during just the next day, meaning that it was going to be six times closer to the Earth! He expressed his amazement on Yahoo's MPML (Minor Planet Mailing List) chatroom on the internet.

"Professional asteroid researcher Alan Harris happened to be monitoring the chatroom and noticed the strange posting about a "bogie" (military slang for an unidentified, potentially enemy aircraft). Indeed, he found on the MPC's web site, with no comment at all, what he recognized to be an alarming prediction. He quickly calculated that an asteroid following this nominal ephemeris would strike the Earth just one day hence. He immediately alerted several of us, including NASA Ames Research Center's David Morrison (who chairs the IAU's Working Group on NEOs) and JPL's Don Yeomans (who heads NASA's NEO Program Office). His message was sent at 5:09 pm (MST, used hereafter, is the time zone of LINEAR and of the amateur astronomer who later laid this bogey to rest).

"Yeomans and his associate Steve Chesley telephoned to the MPC to try to find out more about the asteroid from Spahr. Forty-five precious minutes had already elapsed since Harris' email, when all that Yeomans could report back to his colleagues was, "We've got a call into Tim Spahr to see if we can get the astrometry itself but Tim is not yet at home." About half-an-hour later, they reached Brian Marsden, director of the MPC, who was working late that evening. (Harris also alerted Marsden by email.) By policy, LINEAR and other single-night asteroid data (termed one-night-stands) are kept private by Marsden until they have been verified and linked with observations on other nights. But once contacted by Yeomans and Chesley, Marsden agreed to provide the data to the JPL researchers and did so about 20 minutes later; then, about 1 hour 45 minutes after being notified by Harris, they got to work trying to understand this anomalous asteroid. (Other asteroid orbit experts, in Arizona and Italy, later complained that they never had access to the data on AL00667.)

"The MPC faced the embarrassing fact that they had effectively made the first-ever prediction of a near-term asteroid impact without even realizing it themselves. Marsden hastily tried to fix the web page. Supported by no new observations, he posted a new, non-impacting (actually receding) trajectory, which was also consistent with the data. An hour later, Spahr -- having finished dinner, gone home, logged in and discovered what was happening, and raced back to the MPC -- replaced Marsden's post with yet another trajectory, once again showing the asteroid headed toward the Earth, but this time narrowly missing an impact. None of the later postings reflected new data: Spahr and Marsden were simply frantically trying to figure out for themselves what the data meant and what was politically correct to display on their web site. With hindsight, it is clear that the highest priority should be to search for "virtual impactors" -- that is, the subset of asteroid trajectories allowed by the uncertainties in the fit to the data that would result in an impact; if no asteroid is found in the patch of sky that meets these criteria, then there is no longer a threat of impact. The second priority should be to find the NEO, wherever it might be within the spread of uncertainty, so that it isn't lost. Another priority, of course, is not to confuse, mislead, or frighten people by leaving an effective impact prediction posted on the web site (without appropriate caveats, especially for non-experts who might suddenly be alerted to this web page's existence). With hindsight, we can surely imagine better solutions than any of those implemented on the NEOCP in unplanned crisis-mode that night. But the chief blameworthy error is lack of thorough planning by the NEO community for such a contingency, not in the spur-of-the-moment decisions actually made".

. . . . . . (several paragraphs omitted)

"What can we learn from this case? How could there have been an official, if unmonitored and obscure, posting by the MPC based on a calculation implying a major asteroid impact the following day, without the MPC even realizing it? How could the data, on which the calculation was based, be kept private so that many of the world's asteroid experts could not evaluate the situation, long after the threat was being debated in a public chatroom? How could the JPL Sentry system and the parallel NEODys system in Italy have failed to post the relevant information on their own official asteroid impact web sites? Why were the LINEAR data worse than usual for this particular "one-night-stand"? Were the computer programs used by the MPC and JPL that evening truly state-of-the-art and, if not, did that contribute to the scary predictions? How could one JPL expert calculate something like 1-chance-in-four of a near-term impact disaster, when in fact the asteroid never passed within millions of miles of our planet? Just how big was the nominally calculated impacting body, where would it have hit, and how much damage might it have caused? Did this event merit the unexpectedly high value of 3 on the Torino Scale (designed to educate the public about the seriousness of an impact prediction)? How did this potentially most dramatic of all asteroid impact predictions fail to be noticed by the news media? How close did astronomers come to issuing another false alarm, this time with the potential for embarrassing not only NASA but the White House? What things went wrong, and what things went right during the evening of January 13? Finally, what can be learned from the events so that a more reliable treatment and analysis of Spaceguard Survey data can be accomplished next time?"

THE SAGA OF ASTEROID AL00667 = 2004 AS1

Brian G. Marsden (from CCNet, 15 January 2004)

"That this latest PHA should have generated so much heated discussion on numerous mailing lists and the internet on the basis of four observations covering a time interval of one hour on the morning of Jan. 13 is surely quite amazing. On the routine arrival of the night's LINEAR data at the Minor Planet Center at 5:15 p.m. EST that day, the usual computations on them were quickly done, and, within a matter of minutes, five of the objects were placed on the MPC's WWW "NEO Confirmation Page" as being of potential NEO interest, predictions of the expected positions and their uncertainties being provided in the hope of securing early confirmation from observers in Europe. It was evidently cloudy over most of the continent, however, and the only follow-up observations immediately forthcoming were in fact from a single observer in the U.K. Also according to usual procedures, on the receipt of these U.K. observations, the predictions on the WWW could be quickly and significantly refined, well in time for further observations to be presumably made from North America. There was in fact also rather extensive cloud cover that night over North America, particularly over the numerous professional and amateur observatories in the frequently blessed Southwest.

"At 7:25 p.m. the LINEAR team withdrew one of the day's crop as not real, and this object was removed from the NEOCP. Another object was far to the north, and the single U.K. observer was unable to observe it because at that high declination his CCD camera fouls the fork mounting of his telescope. By that time this particular object, temporarily called AL00667, had attracted the interest of the MPML folk, however, because--curiously--the "nominal" prediction adopted for use on the NEOCP showed that the object would collide with the earth in little over 24 hours! This circumstance had not in fact been noticed by the MPC staff member maintaining the page (who had a dinner date with a visiting professional colleague), although it was of rather limited consequence because he had also delineated the moderately large sky-plane uncertainty area over which follow-up observers could expect to carry out their searches. Unfortunately, as already noted, very few follow-up observers were able to do anything.

"Dinnerless myself, I was still in office (working on the SOHO comets) around 8:30 p.m., when I was alerted to the MPML "crisis" by a telephone call from one of the NASA NEO Program Office staff members. I quickly verified the complaint about the impact, computed several orbits myself that would have the object receding from the earth rather than approaching, supplied the observations to the NASA colleague so that he could do some independent orbit computations (which essentially agreed with those of the MPC), contacted a few potential observers in the U.S., advised my MPC colleagues that "we had a problem", and replaced the offending nominal orbit by one that was less threatening. Of course, what we now urgently needed were _follow-up observations_. All we got, unfortunately, was ever more unnecessary and often quite uninformed "talk" (notably by professionals!) in the MPML." (several additional paragraphs omitted)

INTERNATIONAL ASTRONOMICAL UNION WORKING GROUP ON NEOs WGNEO STATEMENT ON DEALING WITH SHORT-TERM IMPACT PREDICTIONS (posted on WGNEO website 19 February 2004) On the night of January 13/14, 2004, the international asteroid science community faced an unprecedented situation, with an initial prediction of an impact of a small asteroid on the Earth within a few days. The asteroid in question, bearing the temporary designation AL00667, had been discovered the previous night by the LINEAR telescopes of the Spaceguard Survey. Routine and largely automatic processing of these observations led to the posting (by the IAU-supported Minor Planet Center in Cambridge MA) of an orbit that intersected the Earth within the next 36 hours. Although the observations were limited and the orbit solution was highly non-unique, there initially appeared to be a distinct possibility, verified by orbital calculations carried out at the NASA NEO Program Office at JPL, of an impact in the northern hemisphere.

The estimated size of asteroid AL00667, diameter 30 m, was small enough that no serious consequences were expected, but large enough that significant ground damage or possible injury could not be ruled out. The very limited data (from one night's observations) and the preliminary nature of the orbit at no time allowed an estimate of a possible impact site. The situation remained uncertain for several hours, until amateur astronomer Brian Warner, with a 20-inch aperture telescope in Colorado, searched the area where JPL calculations showed that the asteroid would have to be if it were on an actual collision course. Warner's observations were negative, showing that the true orbit for AL00667 did not intersect the Earth. Thus, as Clark Chapman of Southwest Research Institute writes in a paper presented at the American Institute of Aeronautics and Astronautics workshop on protection of the Earth (February 23), "instead of waking up to headlines and TV news specials of an asteroid strike about to happen in the next day or two, life went on as usual around the world." Only a handful of astronomers (professional and amateur) were involved, and there were no scare stories in the press.

Several members of the IAU Working Group on Near Earth Objects were involved in the activity surrounding the possible impact orbit of AL00667, and the Working Group on NEOs seeks to draw some lessons from these events.

First, we stress that there were no significant errors in either data or interpretation made that night. The observations were real, the object did exist (although it turned out to be much farther away than originally thought), and there were orbital solutions that predicted an impact with an apparent probability of at least 10%. Additional observations were required in order to verify that the object was not on a collision course. These observations were of the sort used previously to falsify a dangerous orbit by looking at the place where the asteroid would be if it were on a collision course (sometimes called a process of eliminating a virtual impactor). The IAU WGNEO congratulates those who worked to eliminate this particular threat in a highly professional way, and did so within a few hours, and without negative publicity.

Second, we note that the Spaceguard Survey was not designed to detect small asteroids a few days before collision. It does not have either the equipment or the resources to function as a warning system for imminent impacts. Its purpose is to carry out a long-term survey, with emphasis on discovering and calculating accurate orbits for asteroids larger than 1 km -- those with a possibility of triggering a global catastrophe if they collided with Earth. The Spaceguard goal is to discover 90% of the near-Earth asteroids larger than 1 km by the end of 2008. This approach should provide decades of warning for any impact by these larger asteroids.

Third, the probability that a small asteroid will be discovered within a few days of hitting the Earth is extremely small. While many asteroids might masquerade as impactors based on discovery observations spanning a single night, the great majority of these will be "false alarms."

Finally, however, we note that it is possible for the survey telescopes to pick up a small asteroid on its final approach, and the interested community should decide how cases like AL00667 should be handled in the future. The IAU WGNEO suggests to its members that we consider what actions should be taken to facilitate the determination of a more accurate orbit, and the ways this information should be made available to the public and to interested official groups. The current mode of verification for larger asteroids, including the provision for an optional IAU peer review of orbital calculations, does not apply when there is a possibility of an impact within a few days of discovery. The WGNEO therefore suggests that we should discuss these issues among ourselves and with other interested parties to determine protocols for dealing with such cases in the future. There should be planning at an international level of what action to take with respect to notifying governments and the public of a possible near-term impact. This planning must recognize that it is likely that in all such cases new observations will quickly eliminate any possibility of impact rather than confirm it.

In the meantime, the WGNEO suggests the following two interim guidelines: (1) If any orbital solution for a newly discovered asteroid includes a possible near-term impact, every effort must be made to pursue that possibility (even if it is not the most likely of several possible orbits). The raw data should be available immediately to the community so that experts on asteroid orbits all over the world can be involved in the interpretation and can freely check each other's calculations. (2) Observatories, amateur and professional, should be informed of the high priority to be given to checking the possibility of an impact by searching for the virtual impactor and (hopefully) showing that it is not on a collision course. Searching positions corresponding to a virtual impact orbit should be given priority, as it is more important to eliminate the virtual impactor than to recover the asteroid and compute its correct orbit - the latter will happen routinely within a few days.

David Morrison Chair, IAU WGNEO

Re:Server Unresponsive, Article Text (4, Funny)

jtrascap (526135) | more than 10 years ago | (#8371986)

NASA uses a Cold Fusion server?

Puny Earthlings! We will crush them!

Recognition does not increase likelihood (4, Insightful)

Effugas (2378) | more than 10 years ago | (#8371823)

In the past fifty years, we have started to gain the technological capability to detect potential collisions with asteroids.

That does not make such a collision more likely in the next fifty years -- or hundred and fifty, or fifteen hundred. Significant and successful collision are _rare_, much rarer than earthquakes, tornados, or even human-caused meteorological effects (as in weather systems, not meteors).

It doesn't matter if we can see "just how close we came". It matters that we know, empirically, that there are vastly more pressing concerns.

What I don't want to see is an orbital weapons platform deployed under false premises. If the pretenses are true, that's a different story. Just don't tell me its to shoot down asteroids!

--Dan

Re:Recognition does not increase likelihood (5, Interesting)

Jhon (241832) | more than 10 years ago | (#8371869)

It seems like you are suggesting that this new technological ability to detect NEO's and possible impacts as being similar to the "Boy who cried wolf" fable.

The problem is, as we all know, the wolf finally did arrive one day...

Re:Recognition does not increase likelihood (4, Insightful)

Eivind (15695) | more than 10 years ago | (#8371922)

Sure. We know the chanses are low. Allthough we don't know exactly how low. We *do* know that in the last century alone we've had atleast a few impacts big enough that if they had happened to hit a major city rather than (for example) the tundra in Siberia, tens of thousands of dead would result.

We also know that major impacts, the sort that changes the climate over the entire globe and causes mass extinction of species has happened atleast on a few occasions.

But we don't really know enough to say anything about the true risks. For that reason alone, the first nice thing to do would probably be to increase funding for telescopes, radars and other instruments for better accessing the real risk. That is not a very expensive proposition, as this is an area that is very lowly funded today, a little bit of extra cash will go a long way towards establishing the real risks.

If we should do anything more depends on the risks and the costs of potential defences. It's a cost/benefit calculation.

You are rigth that ICBM-interception-systems are irrelevant for this purpose. All realistic systems for doing something about asteroid-impacts rely on the fact that a small change to the orbit of the thing a long distance from earth will result in a major change, enough to miss the earth, by the time it gets here. Changing the orbit in the last few hours is going to be impractical, it'd require huge amounts of energy. Sligthly more practical migth be blowing the thing up, which would result in a large number of smaller impacts instead of a single big one.

To stop a ICBM you need to hit it with, say, the explosive force of a hand-grenade. That's not going to cut it if you want to blow apart a asteroid of extinction-threathening size.

Re:Recognition does not increase likelihood (1)

fstanchina (564024) | more than 10 years ago | (#8372044)

We also know that major impacts, the sort that changes the climate over the entire globe and causes mass extinction of species has happened atleast on a few occasions.

No we don't. The "few occasions" is just one time about 65 million years ago and it's still pretty much a theory and not a proven fact, AFAIK.

Re:Recognition does not increase likelihood (4, Informative)

Troed (102527) | more than 10 years ago | (#8372106)

Consider it proven (residue left behind as a layer in the soil etc - if you google you'll find quite a lot)

Recent theories suggest the whole solar system moving like a sinus curve up and down through a "cloud" of more-than-usual-objects in the galaxy, and thus every ~30M years or whatever it was there's an increased risk. Several of the almost-everything-killed things that has happened to the earth could be explained this way.

(source: Some issue of Scientific American)

Re:Recognition does not increase likelihood (3, Insightful)

Eivind (15695) | more than 10 years ago | (#8372132)

Proven enough. Granted, there is some uncertanity around details like if the impact was the only reason for the mass extinction, or if other factors also played a role and so on. But there is no serious doubt in the scientific community that the earth was indeed hit by a pretty big asteroid. around the time the dinosaurs died out.

Besides, if you really doubt that this happens, you need only to take a look at the moon. It has no atmosphere which causes smaller asteroids to evaporate before impact, and also helps washing away the signs of impacts after they happen. It's probably a fair bet that the earth gets hit more often than the moon, given that it's so much larger. It's also a fair bet that anything that is big enough to create a major crater on the moon is also big enough to punch trough the atmosphere and create major destruction here.

Re:Recognition does not increase likelihood (1)

fstanchina (564024) | more than 10 years ago | (#8372164)

Sorry for being unclear: I don't doubt that serious impacts happened in the past and will happen again if we wait long enough; it was the "mass extinction" part that I was questioning, but I understand that currently there is some solid evidence for that too, which I couldn't find the last time I checked (some years ago).

Re:Recognition does not increase likelihood (1)

CuriHP (741480) | more than 10 years ago | (#8372513)

There have been several mass extinctions in the Earth's history. The one you refer to is only the most recent. Whether or not some or all were caused by impacts is another story.

Re:Recognition does not increase likelihood (1, Insightful)

Anonymous Coward | more than 10 years ago | (#8372032)

>It doesn't matter if we can see "just how close we came". It matters that we know, empirically, that there are vastly more pressing concerns.
This is a classic mistake, confusing risk with probability.

risk = probability x consequence

And the end-of-the-world-as-we-know-it comes pretty high up on my scale as consequences go.

more info (4, Informative)

gsmb (658454) | more than 10 years ago | (#8371841)

try this link for more info http://www.hohmanntransfer.com/mn/0402/09.htm

PARENT HAS GOATSE LINK (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8371864)

mod down

Only 30 metres? (4, Informative)

Zog The Undeniable (632031) | more than 10 years ago | (#8371853)

That's about the size of the Tunguska object (probably a comet, since it exploded in mid-air and didn't leave a crater). Enough to make a mess of a big city or a pretty impressive tsunami, but not enough to wipe out mankind.

Re:Only 30 metres? (1)

jeff munkyfaces (643988) | more than 10 years ago | (#8372380)

bear in mind that i know absolutly nothing about this: wouldn't an object hitting the earth have a much larger effect than one exploding above the surface?

HA! I am the first! (-1, Troll)

Anonymous Coward | more than 10 years ago | (#8371855)

Ashholes! You saw it!

It missed? (-1, Redundant)

l0wland (463243) | more than 10 years ago | (#8371889)

I think it did hit something! Look what I got when I opened the link:

ERROR
The requested URL could not be retrieved

While trying to retrieve the URL: http://128.102.38.40/impact/news_detail.cfm? [128.102.38.40]

The following error was encountered:

* Connection Failed

The system returned:

(111) Connection refused

The remote host or network may be down. Please try the request again.

Your cache administrator is root.

arbekk (well not artbell) (0)

Anonymous Coward | more than 10 years ago | (#8371915)

But, george noorysp?, has david booth(the dreamer) and wayne green (the guy that thinks we never went to the moon) on coast to coast am. They say were doomed in Septermber 2004. I don't know too much about david booth. I guess it was his dream, but I think they are just scaring folks.

That number.. AL00667 (3, Interesting)

EasyTarget (43516) | more than 10 years ago | (#8371938)

I find the number 667 Highly suspicious..

Is number 666 ever issued? A lot of numberiung systems miss this one out, in order to keep the religeously insane from freaking. For instance the UK number plate authority stopped using it a few years ago after complaints from some quarters.

So my real question is: Would this have -actually- been AL00666?

Spooky...

Re:That number.. AL00667 (0)

Anonymous Coward | more than 10 years ago | (#8371961)

No, it would be number 665, because they also skipped number 13.

Re:That number.. AL00667 (4, Interesting)

October_30th (531777) | more than 10 years ago | (#8372001)

It might actually be a good idea to keep numbering asteroids, license plates, flight numbers, student union cards, social security numbers and so on with a 666 in the code.

Think of it as an early-warning system. Someone who lives his or her life in the fear of getting tainted by a number from a fairy tale should not be let anywhere near positions of power.

Re:That number.. AL00667 (0)

Anonymous Coward | more than 10 years ago | (#8372114)

Well 666 is already on virtually every product you buy. It's in the barcode. Two thin lines next to each other encodes a 6. Every barcode contains three pairs of thin slightly longer lines.....

I would have no problem if there was a 666 in my baraccountnumber or my social security number.

Re:That number.. AL00667 (2, Funny)

judicar (726669) | more than 10 years ago | (#8372029)

Typical slashdotter, an asteroid is about to hit earth and all they can do is bitch about a conspiracy in naming the damn thing.

Re:That number.. AL00667 (3, Funny)

Punchinello (303093) | more than 10 years ago | (#8372135)

667... the neighbor of the beast.

this could have certainly made life more... (4, Funny)

distributed (714952) | more than 10 years ago | (#8372014)

Exciting !!
And maybe my neighbours underground bunker would have finally proven to be useful for things other than coding marathons...

This would also be one hell sure way to get rid of windoze once and for all... only something as distributed as open-source software can survive such a catastrophy... wouldnt it be amazing if entire source code of windows was lost. wow !

Now compare that to the linux source present on millions(?) of computers all over the world. Reminds me of the phoenix...

tisk tisk..
(warning: seriousness levels dangerously low)

Re:this could have certainly made life more... (1)

KingDaveRa (620784) | more than 10 years ago | (#8372228)

The only survivors of apocalypse: Cockroaches and GPL Software.

The media wouldn't survive, but the software would.

Re:this could have certainly made life more... (0)

Anonymous Coward | more than 10 years ago | (#8372300)

Never underestimate the amount of warez copies of windoze. They must be at least as well distributed as open-source software! If the entire windoze source code was lost, it would only affect the few paying customers of M$. Nobody seems to want the windoze source code anyway execpt some crackers and virus writers.

Animation (4, Informative)

jmichaelg (148257) | more than 10 years ago | (#8372058)

Here's an animation [demon.co.uk] of the object. The link [yahoo.com] to the yahoo egroup discussion is also worth looking at. The discussion morphs from everyone thinking it's a joke post to realizing that the asteroid exists. It's an interesting log of people coping with uncertainty.

Natural diaster... (1, Flamebait)

NeoGeo64 (672698) | more than 10 years ago | (#8372111)

Mod me down as flaimbait or whatever, but I personally think we need a global cataclysm. We don't need something that kills off the entire human population, but we certainly need something to cleanse our planet.

We need something to take our collective heads out of our asses and come together as one people and work together for the common good.

The world as it is... is in a sad state. I don't think I even need to explain why... just watch the censored news.

But... (2, Insightful)

sunbeam60 (653344) | more than 10 years ago | (#8372488)

The news told me everything was good and everybody was happy, so I really don't see your point :)

Follow up article? (2, Funny)

ozbird (127571) | more than 10 years ago | (#8372152)

I'm waiting for the follow up article: "The Slashdotting that hit without warning."

Missed due to Slashdot (2, Funny)

rodney dill (631059) | more than 10 years ago | (#8372233)

... Much like the server with the article, the Asteroid was slashdotted causing it to malfunction and miss the earth.

Mirror? (1)

Trikenstein (571493) | more than 10 years ago | (#8372308)

They appear to have been /.'ed

Only tracking asteroids over 1km in size? (1)

voss (52565) | more than 10 years ago | (#8372423)

What if Iron asteroid 1/2 km in size plunges into earths atmosphere? Would that not have a significant impact?
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