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Schoolboy Corrects NASA's Math On Killer Asteroid
spiracle writes "A German schoolboy, Nico Marquardt, has revised NASA's figures for the chances that the Apophis asteroid will hit earth. Apparently if the asteroid hits a satellite in 2029, its path could be diverted enough to cause it to collide with Earth on the next orbit, in 2036. NASA had calculated the chances as 1 in 45,000 but the 13-year-old, in his science project, made it 1 in 450. NASA agreed." Update: 04/16 16:47 GMT by Z : This is not entirely accurate, it turns out — more details.
A friend of mine "used" to work at NASA JSC. He would tell me stories of people with a clue being broken by people in charge that had no clue. He finally got fed up and left... He is not alone.
What's Plan B?
Giant laser? Kinetic kill vehicles?
Nuke it from orbit?
fallout shelters won't help.
It would interesting if funding in SpaceX and the other alt-space companies went up as a result of this.
Rich people: get us off this rock.
How we know is more important than what we know.
I want to see the math. What miscalculation did NASA make? Did they use centimeters instead of meters? Was it a simple math error? Did they use an incorrect statistic?
Why did the kid have access to this information?
I call bullshit on this story. You can clearly see that NASA hasn't "agreed" at all.
A 1 in 450 chance that this thing will hit an asteroid in the way that makes it MORE likely to hit Earth?
Hitting anything in space is like hitting a needle in a haystack. Actually, that's vastly understating it.
There better be an explanation of exactly what it is going to hit and how it will "improve" its trajectory.
http://lkml.org/lkml/2005/8/20/95
... it will create a ball of iron and iridium 320 metres (1049 feet) wide and weighing 200 billion tonnesNext week: 13 year old boy discovers new chemical reaction in which a combination of scientifically illiterate PR bunnies and sub-editors produces large quantities of bullshit.
> 26,000 Hirshimas
So a little less than 1 Mt St Helens then.
Maybe it's in the genes...
$META_SIG_JOKE
Here's a little detail to add to it. None of the satellites we'll be using in 2029 when it passes are in space right now cuz the recommended lifespan of satellites is like 8-12 years or something. Oh and if it hits a satellite, it can be deflected ANY direction depending on where it gets hit. Anyone ever played pool before? That alone puts it to about on in a trillion. And then we don't know if that new path will cause it to collide with another object in the solar system during its huge orbit which would deflect it nowhere near us. We could just barely put together some remotely accurate numbers if we knew the speed and direction of every object and know every particle and force in our solar system plus a map of all the gravitional forces caused by them the entire time. Nasa and the german kid are kidding themselves if they think that either of their guesses is accurate.
Google's Super Secret Search Algorithm: SELECT @search_results FROM internet WHERE @search_results = 'good'
May I add that NASA, at least currently, doesn't even mention this? http://neo.jpl.nasa.gov/apophis/ Where do they get this info, if this isn't anywhere on NASA?
That's the depressing part.
To answer your question: Probably a few months after the 2027 encounter (and hypothetical collision with the satellite), but at that point, it'll be impossible to do anything about it in the 9 years between 2027 and 2036.
The right strategy is to use the 20 years between now and 2027 to build an orbiter/lander (with a big-ass nuke, nuclear reactor powering a big-ass laser, or big-ass solar sail of reflective/absorptive paint -- and as much as I like nukes, the big can of paint's probably the best way to go -- attached).
We use the 20 years to build the orbiter/lander. We send it up to rendezvous or orbit in 2027. If Apophis smacks into a satellite (or we're just unlucky), we'll have an orbiter and countermeasures in orbit around the asteroid on that pass, and those countermeasures will have nine years in which to do their work. A nuke's pretty cool, but it can't compete with nine years of momentum transfer from the sun shining on a rock painted white on one side and black on the other side.
Suppose we cut it short and by 2027 we still don't have any good countermeasures - just a crappy-ass nuke as a last-ditch measure. Even if we go this route, we've still got 9 years for this orbiter to give us an exact gravity map of this object, and we'll have a couple of years after that to figure out where to land the nuke for maximum trajectory deflection away from the earth. (Hell, if we get the orbiter up there early enough in 2027, we can blow the nuke at/near closest approach to Earth and guarantee a miss in 2036!)
But we're short-sighted. So we'll do nothing between now and 2027. And odds are it'll sail on by in 2027 and we'll conclude that the odds of an impact in 2036 are only one in a few tens of thousands. But what an irony -- if we're wrong, then it'll be too late in 2028 for us to send anything to catch up to the rock and do anything about it. For the sake of a month's pork-barrel spending in Iraq, we'll condemn a few billion of our fellow humans to certain death in 2036.
If it's not Apophis, it'll be some other rock in the next few centuries. Just like the dinosaurs, we'll go extinct because we don't have a space programme. Unlike the dinosaurs, this time around, we'll deserve it.
He is from a country where they teach terrorist sciences like Mathematics, Physics, Chemistry, etc in school. I would not be so sure.
He would not have the political drive to lie either.
Baker's Law: Misery no longer loves company. Nowadays it insists on it
http://www.sigsegv.cx/
Live today, because you never know what tomorrow brings
Also on the theme of Mount St. Helens, it stopped building the dome inside the crater at about the same time as swarms of earthquakes were detected off the coast of Oregon (usually a precursor to volcanic activity). There are no volcanos in the area the earthquakes were detected, so vulcanologists have ascribed the tremors (reaching 5.5 on the richter scale) to a shift in the magma flow. There was no suggestion - as far as I can tell - that the lack of mountain-building and the earthquakes were linked, but it wouldn't shock me. If that is corrct, then there's an awful lot of molten rock going somewhere - the dome was building a dumptruck's worth of rock per second, according to one quote I saw - and there are a lot of volcanos considered overdue for exploding.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
There, I hope that gave you a flavor. BTW, there is no mention here either of any named individual in NASA or ESA that is standing behind the numbers quoted.
The article is breathless about how wonderfully catastrophic this all is, but I do have some questions about the math. For one, are there really 40,000 satellites in geostationary orbit (or geosynchronous orbit)? That's the quoted number - I was under the impression that there were rather fewer. And how on earth do they get a figure of 1:450 that the satellite will hit one of them? And that that hit will guarantee the catastrophic outcome they so desire?
For another, I'm not getting a picture of a long observational period and multiple telescopes. Only one telescope is mentioned, and the science fair aspect makes it more suspicious. It looks more like a novel hypothesis ("what if it rams a satellite?") combined with some serious guesswork.
And finally, did anybody else get a little bothered by the description of a 160-meter radius asteroid that weighs 200 billion tons? That gives a density of a little under 12 kilograms per cubic centimeter, which would make it a rather unique and valuable material. As near as I can tell, Wikipedia being your friend and all, they missed by three orders of magnitude. Speaking of correcting the numbers...
We are developing several strategies to deflect the course of asteroids. If these mature over the next few years before our close encounters with Apophis, we may have the chance of bringing into Earth orbit, providing nearby and easily accessible resources for space construction.
Providing it with enough energy to slow from solar orbit to Earth orbit could be tricky, so I suggest the best way is to deflected in such a way it undergoes aerocapture.
People always seem concerned about the possibility of the rock just smacking into Earth, and think this is a reason not to pursue such a strategy. Tell me, am I being too Lex Luthor about this?
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
Joseph Davidovits believes that the Egyptians used fly ash, powdered limestone, natron salt, and water to make "pourable limestone" or Geopolymers that they then used to pour the pyramids at Giza. The main benefit of Geopolymers is that they last longer than Portland Cement and they are a carbon sink not a carbon emitter.
It gets deflected by a small degree, but because this object makes close approaches to large objects like Earth, small impulses can have their affect amplified.First off... how does a 200,000,000,000 tonne asteroid (200,000,000,000,000 kg) travelling at any substantial inter-planetary speed be deflected by a satellite travelling at 3070 m/s and at most wieghing 10,000kg?
This object is in an orbit which resonates with our own orbit. It is certain to continue close approaches with Earth until either (1) it hits us or (2) is thrown into a totally different orbit, most likely as a result of a very close approach.
http://michaelsmith.id.au
The style of explosion is rather different, and I suspect the Mt. St. Helens "Hiroshima" comparison is exaggerated by several orders of magnitude (e.g., Krakatoa -- a much bigger eruption -- is estimated at 13000x Hiroshima, so something is seriously wrong somewhere).
:-)
Anyway, in the case of Mt. St. Helens it was a "lateral blast" -- that is, most of the pyroclastic explosion was directed laterally. This was especially bad for conditions on the ground, but made the amount of material expelled into the atmosphere somewhat less than if it had been vertical. On the scale of volcanic eruptions Mt. St. Helens is a piddly little thing. For example, the Mount Pinatubo eruption in 1991 in the Phillipines was much bigger.
In the case of an asteroid impact of this scale the explosion occurs at the end of a shaft of rarified atmosphere produced by the passage of the asteroid. This means the explosion products will shoot back up the path of the asteroid and be much more widely dispersed world-wide. There is also the high chance of a mega-tsunami, which also spreads out the effect.
Apophis is supposed to be ~350m in dimensions. Any way you consider the question the effects would be a whole lot worse than Mt. St. Helens. The effect would definitely be on a global scale.
A more comparable volcanic eruption is Krakatoa which erupted in 1883 and generated a tsunami and climatic effects world-wide -- except that Krakatoa was ~200 megatons equivalent, whereas estimates for Apophis' impact are ~880 megatons, so the explosion is still bigger -- closer to the scale of Mount Tambora (1815). We're talking about an explosion on a scale that would be on par with the biggest ever observed. Even away from the direct impact effects we are talking about widespread/global crop failures as a result of atmospheric dust and cooling. The 1815 "Year Without A Summer" from the Tambora eruption is probably a decent comparison.
It would be a bad day for everybody. On the plus side, it might slow global warming for a few years
9/11 Eyewitnesses to Explosive WTC Demolition 1 of 2
I'll play along. I'm qualified to do so on this forum: I've read slashdot for years and I've never studied orbital mechanics or anything else pertinent to the subject.
The original NASA estimate was based on the probability that on the previous orbit Apophis would hit a small window of opportunity that would slingshot it around Earth into the final collision orbit. What the kid did was demonstrate that the window is actually much larger than NASA had first estimated, since collisions with small stuff known to be orbiting the Earth could funnel Apophis into the slingshot zone.
Oh, you wanted a car anology:
Consider a photographer at an auto race who has jumped the safety barrier to get some real good photos of the cars roaring into a hairpin turn. He knows that there is some small risk that a car will spin out as it approaches him and smash him flat, but to his mind it is an extremely low risk. There is only a narrow trajectory that would cause him danger.
But what if a bunch of ball bearings had been strewn onto the track in front of the curve? That changes the whole equation: if a race car teetering on the verge of spinning out hits one of these, it is much more likely to plow into the luckless photographer. The range of dangerous trajectories is much wider than the photographer estimated, since the track is not as clean as he pictured it in his mental model.
even tiny velocity changes (well below 1m/s) had huge effects on the rest of the trajectory.
Yes, but a strike from a satellite will impart certainly less than 1mm/s. And you're talking about your senior design program. This is a schoolboy we're talking about here. I doubt he has bested you.
I remain skeptical of this story. I'd like to see it *researched* and reported by a reputable source. I'd like to see it posted on a NASA website. So far, what I've seen is that what amounts to a tabloid posted the story and some other news agencies have parroted it, apparently without doing any original research.
I think this story is a hoax.