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Asteroid 4179 Toutatis Will Miss Earth, This Time
EtherAlchemist writes "National Geographic News reports in this story that a giant, peanut shaped asteroid known as 4179 Toutatis will pass within 1 million miles of Earth on Weds, the 29th. When it does, it will be the closest any known object of this size (3 miles) has passed near Earth in this century. No worry about impact yet, it should pose no threat until at least 2562. An interesting note: the asteroid believed to have caused Earth's biggest mass extinction is thought to have been between 3.7 and 7.5 miles as reported here in 2001." 2004 FU162 came closer, but is a much smaller object.
When it does, it will be the closest any known object of this size (3 miles) has passed near Earth in this century.
Wow! You mean to tell me it's the largest object to pass near here in over 3 years!!!
OK, one of those things that sounds impressive, then when one thinks a little, isn't all that big a deal...
"Leo Fender was in a 'state of grace' when he designed the Stratocaster." -- Paul Reed Smith
So close to not having to pay next months rent
what if we knew for sure we would be hit in 500 years? that's long enough to be none of our problems. so would people say "fuck them" and just leave it to some other generation to sort out, or be willing to pay for a huge programme to deflect/destroy it?
it's a similar problem to global warming, except there are no asteroid-impact-dependent business models funding research and laws like with oil.
... seems the sky missed us this time! ;)
I, for one, would like to welcome our new oven-roasted overlords...
Here's the proof. Free 27" flatscreen TV.
Forget Death star check the Death Peanut.
http://ebgp.net/ccc/
The mean distance between the Earth and moon is 384,400 kilometers. 1,000,000 miles is about 1,609,000 kilometers, so the asteroid will come within about 4.2 earth-moon distances.
150 Opening BINARY mode data connection for slashdot.sig (129323052 bytes).
I'm getting kind of sick of this type of story. It seems like every few months their are stories released about some space object coming close to earth and 'just barely missing'.
Though I am curious to know if their is an official plan for countering a colliding asteriod? What would our options be realistically if an asteriod going to impact in a matter of months?
I'll make you a deal. You pray to God for help and I'll stop the moment he shows up.
Didn't you see Armageddon? You can't do that...we must send Bruce Willis to mine holes and gently plant the explosives. Geez...
A computer once beat me at chess, but it was no match for me at kick boxing.
Method 1 is novel, but probably wouldn't produce enough of a course change to matter... we'd still die (remember we're unlikely to spot an asteroid until it's way too a late for minor course changes to make a difference).
Method 2 plain wouldn't work. Asteroids aren't solid objects so they can absorb a lot of shock, plus if you managed to break it up all the little bits would have the same total velocity as the original asteroid... death by a thousand cuts.
NASA's NEO (Near Earth Object) program tracks many different objects, though I wish they had a bigger budget, then they could handle even more.
That is the meaning of the grandparent post.
You do realise surely that 1000 small asteroids is a lot better than 1 large asteroid, right? The effect of 1000 small chunks would be greatly reduced due to them burning up faster while descending through the atmosphere. Same total velocity my ass, i'm all up for air resistance.
telling the public would be stupid... so we won't know about it
Not at all. The news would probably leak out, and there would still be a panic.
What you really want to do is tell people about the rock, but tell them it'll just a be a near miss, a million miles or some such. Nothing to worry about.
Wouldn't it be easier to say 6 to 12 Km?
sigh.
An interesting note: the asteroid believed to have caused Earth's biggest mass extinction is thought to have been between 3.7 and 7.5 miles as reported here in 2001
I was just watching something the other day on the History channel about a recent find. A huge lot of dinosaurs buried under meters of volcanic ash - sort of hinting a giant volcano blast may have done all the dirt work.
I tried to google for some more info, but came up empty-handed. I did find this article though, about dinosaurs found in Alaska. It states that if they had managed to adapt to an arctic environment, then the "nuclear winter" effect of a large meteor hitting earth may not hold as much water.
Then again, I doubt we'll ever truly know - maybe the dinosaurs just got tired of living and went the way of the Heaven's Gate members.
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Anatomically modern humans have been around about a hundred thousand years. That's roughly five or six THOUSAND generations. The chances that we get smacked by an asteroid within the lifetime of the first couple of generations that actually have a chance to see it coming is remote.
Yes, it would be bad.
Yes, it's going to happen if we don't stop it.
No, it's not going to happen in your lifetime.
No, I'm not giving you lots of money to try to stop one with primitive turn-of-the-millennium technology. When legitimate investments in space travel bring the cost of launch down and our robotics/sensors are better and our deep space propulsion systems are better, THEN I'll vote for spending money on a decent system.
Or I would, if I wasn't going to die in the global bio-weapons apocalypse of 2027.
That is quite the appropriate letter sequence for an asteroid that comes close to earth.
"This is you left and that's your left. This is your right and that's your right. You're gonna die!
1000 pieces of a 3-mile asteroid are each 0.3 miles (0.5km) in diameter. The atmosphere is barely going to singe a rock of that size before it impacts.
Even if were blown to tiny pieces, that wouldn't help. Scientific American had a recent article that hypothesized that one of the worst parts of a big impact is the rebound of billions of tiny fragments into space, which then rain down all over the globe. Each one burns up individually, but the overall effect heats the entire atmosphere to hundreds of degrees, incinerating just about everything on the planet.
Sliced big or small, that much mass coming in from outer space would be a major problem.
Why?
Because a billion tons of gravel travelling at 25,000 miles per hour is just as deadly as a billion ton chunk of rock travelling at 25,000 miles per hour. It's not the rock itself that's the problem. It's the kinetic energy from the object's mass that's the problem. Gravel - rock - it's all the same at 25,000 miles per hour...
The only way a nuke really would work would be if it were small enough to nudge it off course, wihich would mean getting a BIG lead time on it. and that assumes that the asteroid is solid. It seems a lot of them aren't all thet well put together and a nuke would only turn the bullet/asteroid into a shotgun blast, per my previous description.
RS
Shoes for Industry. Shoes for the Dead.
...and park it at one of the Lagrange points? Something that massive would be much better for an international space station than a few hundred tons in low earth orbit, and it would provide more than enough shielding for any conceivable solar flare.
I'm not sure about that. Blasting the asteroid into gravel would greatly increase its total surface area. More surface area + same velocity = more heat generated from friction with the atmosphere. Therefore more of its mass would burn up before striking the earth.
"The advanced societies of the future will be driven by competing systems of psychopathology." -JG Ballard
What if two nukes were sent. One to break the astroid into thousands of pieces and the second to distribute those pieces over a greater amount of area?
Even if such an object hit Earth, I seriously doubt that it would lead to human extinction. In fact, it probably won't even kill as many people as the tens, or possibly even hundreds, of millions we have killed during the 20th century in two world wars, many other wars, and persistent indifference to humanitarian crises of famine or disease. This may be a young crowd, but those of us old enough who have grown up during the heat of the cold war will probably have less to worry about from a meteor hitting than all those tens of thousands of ICBM the USA and USSR seemed willing to unleash on each other and everyone at a very short notice.
Many species survived many mass extinction events, and, ironically and in fact, many of such species have been, or are being, driven to extinction by none other than us. Soon we will have successfully driven biodiversity to the minimum we have allowed to survive because we want it, such as dairy and poultry farms, and pets.
I am willing to bet that the last surviving species on Earth will be humans and microbes.
> Therefore more of its mass would burn up before striking the earth.
And dump the heat into the atmosphere. Congratulations you have just managed to convert the energy from a kinetic impact into a heat event probably affecting a much wider range than before.
The choices
A) smashed: solid ground absorbes energy
B) broiled: atmosphere absorbs energy
The key to method one is pinpointing the exact orbits of all the asteroids that possibly might hit us, and run computer simulations to find any that will hit us in the next hundred or thousand years. If you have that much warning the light reflection method would probbably work.
AccountKiller
But the moon doesn't have an atmosphere or oceans, so most of those things simply won't happen - lots of dust goes ballistic and lands, a chunk of the moon's surface gets vaporized (ok, causing a temporary localized atmosphere of sorts, but not enough to care about), and the dust covers some existing craters, but if there's a new crater on a side of the moon we can see, maybe it'd be deep enough to get some real insight about the inside of the moon.
Certainly lots of business for astronomers for a while. It'd be much more annoying if it hit the far side of the moon where we can only see it from spaceships.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
I dunno. My experience with asteroids is that the smaller the chunks, the faster they travel. Same with the flying saucers.
That's the last time I run code posted in somebody's sig...
it actually runs gentoo. It's still compiling as we speak. That's why it avoided us, so it can finish its compile.
Does anyone ever run trajectory calculations for a strike on the Moon, rather than Earth? And what size Moon strike would cause problems here? Could the moon eject a chunk in our direction sufficiently large to be a problem? For that matter, what would happen to the Moon in that situation?
Too many questions -- no idea of the impact (pun intended.)
-- Gary Goldberg KA3ZYW 301/249-6501 AIM:OgGreeb Digital Marketing Inc., Bowie, MD
...but every time I see one of these stories, I think of some extremely long-lived alien warlord interns having a conversation like this:
Braxxis009A - "Idiots! How many times do I have to tell you anthropods even a trillionth of a degree of miscalculation will cause a complete and total miss! Now reload the Meteoro 2000 Planet Blaster XL with another rock and GET IT RIGHT THIS TIME!!!!"
It all depends on how big it is, how fast it is, and where it is going, where it gets turned to gravel and how big the gravel is. If it is far enough out most of the gravel will completely miss, if it is too close in it and a lot of it will simply be like worrying whether a puppy will be hurt more by a shotgun or .44 at medium range.
There's a lot of room between the rocks out there. If something is big and fast the earths gravity won't change its course much to pull it in, we are a moving target, and nothing is aiming for us anyway.
3 miles = 4.827 Kilometers
4.827 / 1000 = 4.827 meters
Volume is proportional to diameter cubed. Now you're talking about 1 billion asteroids, not 1000. Come on, this is 6th grade-level math. It can't be that hard to understand.
Let's do the math on burning the asteroid up in the atmosphere. Assume you have a 3-mile diameter asteroid going at 50,000mph. That's 5.7e10 m^3 of rock; assuming 5 tons/m^3, mass = 2.9e14 kg. Energy = 0.5mv^2 = 7.2e22 joules.
Assume a blob of gravel of this mass hits one side of the earth evenly distributed over an entire hemisphere over a 1 minute time span. That deposits the energy over 2.6e14 m^2 surface area in 60 seconds, for a total power flux of 4.6 megawatts per square meter of the entire earth; about 4000X the brightness of the sun for 1 minute. Even if the burnup occurs high in the atmosphere, the power influx at the surface would not diminish because the radiation is coming from the whole sky, not from a point source.
Bottom line, everything would fry.
- Both solar and thermal radiation exert pressure.
- The incoming solar radiation pushes away from the Sun, but the thermal re-radiation from the asteroid pushes away from the hottest parts.
- Asteroids rotate, so the thermal-radiation pressure is not directly away from the Sun but away from the "afternoon" part. The lower the albedo (darker) and the greater the thermal conductivity (lag between peak insolation and peak temperature), the greater the difference between the direction to the Sun and the thrust vector.
By painting the asteroid whiter (or, in theory, darker) you change the amount of heat absorbed and thus the ratio between the thrust from the reflected light (tracks exactly with incoming light) and the thrust from the radiated heat. Given enough time this will let you change the orbit of the rock enough to miss (or possibly hit) what you want it to. This works best with smaller bodies and long (very long) lead times.Sustainability and energy independence essay
If you blow up an asteroid of some arbitrary tonnage, say, a nice round billion tons, the planet is STILL fucked. Why?
Simple, and I repeat, a billion tons of gravel is still a billion tons of rock. Sure: there is more surface area and greater heating, BUT - all you have done is taken a catastrophic impact event of a billion tons of rock hitting several quintillion tons of rock (earth) into a billion tons of rock hitting a few million tons of air. At 25,000 mph, the kinetic energy of a billion tons of gravel will get converted directly into heat. So instead of a giant pinpoint nuke going off, it would turn a larger area of the planet into something like a broiler set on HIGH, and this heat event would last quite a long time, as anything that can burn will burn (explosively). Net effect: we all die.
Also: hitting it with a nuke ASSUMES it will *ALL* be reduced to gravel, and this isn't necessarily true. Many asteroids aren't that well put together, and there is a greater chance that by setting off a nuke on an asteroid, instead of a billion ton rock hitting in one spot, you could as easily end up with, say, four 200 million ton rocks all plowing into roughly the same little patch on earth AND 200 million tons of sand, gravel, frozen gasses, and other crap to turn the place into the solar system's biggest hibachi.
I can assure you what I speak is true - IANAAP (I am not an astrophysicist) but I have friends who are, and they all tell me the exact same thing:
blowing it up only works in (bad) hollywood movies.
You can't live outside the law of the conservation of mass and energy. A billion (or more) tons of rock is still a billion tons of rock, and when it's travelling at 25,000 miles per hour, it'll blow through 100 miles of atmosphere in about (but not a lot more) than a quarter of a second. BOOM. Game Over.
So, to re-iterate for the jillionth time:
BLOWING UP AN ASTEROID REALLY DOESN'T WORK. PERIOD. REALLY.
RS
Shoes for Industry. Shoes for the Dead.
We do have some meteorites which are known to have come from the moon, so it's proven that stuff kicked off of there can wind up here. It's also pretty obvious that the pieces that wind up here are nowhere near as big as what smacked the moon in the first place.
Sustainability and energy independence essay
Upon further consideration, I've come to the conclusion that if an asteroid that big did collide with the Earth ... the complete destruction of all life on the planet would be a small price to pay for finally getting rid of Microsoft.
(It's funny. Laugh.)
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Even if we could find a way to detonate every nuclear weapon we possess, at the same spot, on a 3 mile diameter asteroid it is not going to turn it into gravel; the asteroid will have it's orbit altered some, and *possibly* would fracture along it's internal fault lines.
The most likely result of such a fracture would be a small number of rocks with diameters ranging from a few tens of meters to hundreds of thousands of meters, and a small amount of gravel. A lot of that depends on what the composition of the asteroid is. If it's carbonaceous - like comets - there would be smaller fragments - if it's a stony or iron composition, it's unlikely we'd be able to fracture it at all, or if we could, then into very large chunks.
The REAL migraine there is that if the result was a lot of big chunks, their orbits would be altered enough that it's possible that they'd touch down at points distributed along the line of the Earth's rotation, thereby distributing the destruction even more widely. Remember, even a large ~ 3-8km-diameter asteroid's impact zone will be somewhat localized - even if it did alter the global climate, the worst effects would stay within one hemisphere. Not so with a time-distributed impact of many semi-large rocks.
Anything along these lines will have to be contemplated and modelled VERY carefully; the best data we could get would be if we had time to land probes on the asteroid in question and get seismic soundings of it's structure, and even then we'd still be playing with a lot of uncertaintities.
We should be pursuing studies and sending probes like this right now, so that if in the future the necessity emerges we at least have a good amount of data on many different rocks to use in our calculations, rather than some hurried-up last minute/year effort. But hell, this is all gibberish to most of those morons who make policy anyway, so what's the point of arguing it anymore in the public venue? Well, we need funding for those probes and studies... and like many other issues that need attention, this one is being ignored this year in favor of arguing over people's fucking war records from thirty years ago, and this in the country that is the world's most technologically capable society.
Sometimes I wonder if humanity as a whole hasn't already drank the koolaid.
slash rant
Sigh. Goddamn I hate election years.
SB
It's old. The more humans I meet, the more I like my cats. At least they are honest.
The question can be formulated this way: If an asteroid came whizzing close by, what is the probability it would hit the moon?
Well, the earth's diameter is four times the moon's, so the area it presents is sixteen times the moon's. Therefore the probability of hitting the earth is sixteen times that of hitting the moon, and we really should be at least 16 times as worried about earth impacts as moon impacts.
Further, the orbit of the moon is 60 times the size of the earth, so the area it presents is 3600 times the area the earth presents. If an asteroid comes whizzing through, inside the moon's orbit (an unlikely event in itself), its probability of missing is 3600 times it hitting the earth or the moon.
Take a one cubic mile mass of solid granite. 5280 x 5280 x 5280 (cubic mile) x 170 lbs (one cubic foot of granite) and you get:
25,023,651,840,000 pounds, or
12,511,825,920 tons
this is an object MUCH SMALLER than the asteroid in question. In fact, I would say it is 1/4 the size of the obect in question, but I doubt the asteroid Toutanis is made completely of granite. It's probably part rock, iron, and ice like most of these things, and so it's mass (my pure out of my ass guess) is probably only 2 - 3 times that a 1 cubic mile of granite. so let's be generous to the ice-side and say 2.5 times. that would be:
31,279,564,800 TONS.
THIRTY ONE BILLION TONS.
OK....
And it's what?: 2.7 miles x 1.3 miles (roughly). Which means it is probably tumbling through space and is (obviously) not spherical. so you blow it up in the middle and you get TWO big chunks of say 15 billion tons each and a billion or so tons of gravel and million ton objects.
So, what say we put THAT in a trajectory through space in such a way that it directly impact over your head. Better yet: I'll even give you some room: I'll put you 500 miles away.
And THIS is what would happen, and this is assuming it's made out of average loose crap and I averaged it to a 2 mile object:
(per this site: asteroid impact effects calculator
Your Inputs:
Distance from Impact: 805.00 km = 499.90 miles
Projectile Diameter: 3218.68 m = 10557.27 ft = 2.00 miles
Projectile Density: 1500 kg/m3
Impact Velocity: 20.00 km/s = 12.42 miles/s
Impact Angle: 90 degrees
Target Density: 2500 kg/m3
Target Type: Sedimentary Rock
Energy: Energy before atmospheric entry: 5.24 x 1021
Joules = 1.25 x 106 MegaTons TNT. The average interval between impacts of this size somewhere on Earth during the last 4 billion years is 5.4 x 10^6years
Atmospheric Entry:
The projectile begins to breakup at an altitude of 75100 meters = 246000 ft. The projectile reaches the ground in a broken condition. The mass of projectile strikes the surface at velocity 19.9 km/s = 12.4 miles/s. The impact energy is 5.19 x 1021 Joules = 1.24 x 106MegaTons. The broken projectile fragments strike the ground in an ellipse of dimension 3.32 km by 3.32 km
Transient Crater Diameter: 25.2 km = 15.6 miles. Transient Crater Depth: 8.89 km = 5.52 miles
Final Crater Diameter: 38.5 km = 23.9 miles. Final Crater Depth: 0.888 km = 0.551 miles
The crater formed is a complex crater.
The volume of the target melted or vaporized is 46.2 km3 = 11.1 miles. Roughly half the melt remains in the crater , where its average thickness is 93 meters = 305 feet
Seismic Effects: The major seismic shaking will arrive at approximately 161 seconds.Richter Scale Magnitude: 8.7.Mercalli Scale Intensity at a distance of 805 km:
III. Felt quite noticeably by persons indoors, especially on upper floors of buildings. Many people do not recognize it as an earthquake. Standing motor cars may rock slightly. Vibrations similar to the passing of a truck.
IV. Felt indoors by many, outdoors by few during the day. At night, some awakened. Dishes, windows, doors disturbed; walls make cracking sound. Sensation like heavy truck striking building. Standing motor cars rocked noticeably.
Ejecta:
The ejecta will arrive approximately 436 seconds after the impact. At your position the ejecta arrives in scattered fragments
Average Ejecta Thickness: 7.99 mm = 0.315 inches
Mean Fragment Diameter: 1.01 mm = 0.0396 inches
Air Blast:
The air blast will arrive at approximately 2440 seconds.
Peak Overpressure: 13600 Pa = 0.136 bars = 1.93 psi
Max wind velocity: 30.3 m/s = 67.9 mph
Sound Intensity: 83 dB (
Shoes for Industry. Shoes for the Dead.
Fuck that! Send all the nukes we have! It's not like if it fails we still have anything left to do with them...
No, they're not. The arguments in those posts assume that the rubble hits just as the main body would have; that's only true if the blast is very late. The arguments in those posts assume that 100% of the energy of the impact is radiated downward. That's not true at all. Those arguments assume that all of the rubble delivers all of it's kinetic energy as heat directed downwards. Neither is true - it's not all heat, and it's not all directed downwards. All of these assumptions are the consequence of simplistic thinking.
In short: blasting an asteroid of that size into dust means we get hit with some million H-Bombs equivalent, blasting the atmosphere away or heating it up to several thousand degree celsius. Only ocean life, plancton etc. and microbs will survive that.
This is incorrect. The reason that it is incorrect is because when a blast large enough to fragment a body of that size is applied, the body will alter its vector significantly. If the blast is applied to the side, and in a sufficient amount of time, the vector will cause the rubble to miss.
Getting an impact by a solid block causes earthquakes, an eruption, "nucelar winter" and tsunamies etc. However even some people might survive elswhere.
Yes. However, you completly miss the point. The objective here is to miss getting hit by either the block, or the majority of its fragments. That is quite aside from the simplistic - and incorrect - assumption that 100% of the kinetic energy will be delivered if the object is converted to rubble.
I understand those terms, likely you used them corectly. But: if you understand the terms as well, the formulars to calculate how big the "sideways momentum" might be, if a singel h-bomb makes close hit, are EASY. So you will figure you are wrong if you just enter the numbers.
Obviously, if we're talking about the same object we started talking about, we're not talking about "a single h-bomb." If you want to break an object the size of the "peanut" into 1000 fragments (other than one really big one and 999 really small ones) then you'll be using a lot more force than a single bomb can deliver. h-bombs aren't magic. Now: If instead you figure the force required to fragment the thing into more or less equal rubble, you will find that the forces imparted to the original vector are not insignificant, either from the blasts and/or from large parts of the object being turned into high-velocity gas and dust going in a new direction.
Plasma and shockwave: well, a shockwave moves with a speed about the sound barrier ( a small multiply). The impacting particles, in case of dust, are up to 50 times faster.
Speed is not the issue. How hard the air is, is the issue. Think about it.
I simply can not see how the shockwave of one of those particles should shield the earth against the following ones :D
Well, stick your face outside a jet cockpit at mach 1, and you'll learn. Well, your next of kin will learn. :) Or, shoot a single tiny 22 caliber bullet into an oil drum filled with water. Watch what happens to the lid. Shock waves are nothing to discount.
Especially as that wave moves in circles away from the impact point and not up behind the impacting body.
As you observed above, the speed that the shock wave travels isn't much compared to the incoming bodies. Therefore, the incoming bodies will run into the shockwaves. Rock hard air meeets rock. Bang. With the rock hard air between the result and the earth, mind you.
Finally: if the upper athmosphere gets heated up, like you think it will not harm us: it gets heated to about 3000 degrees. How long can you take a sun bath under a sky with that temperature in a distance/hight of just a few kilometers?
The issue isn't how hot a spot gets, it is, how many spots get that ho
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