Asteroid Once Seen As Dangerous Offers Chance For Close Study

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Asteroid Once Seen As Dangerous Offers Chance For Close Study

Posted by CmdrTaco on Monday January 31, 2011 @06:21AM from the no-relationship-to-sg1 dept.

RedEaredSlider writes "An asteroid that once was seen as a danger to the Earth may soon provide a once-in-a-century opportunity to get a close look at one — and learn more about the ones that really are a hazard. The asteroid is called Apophis. It's a near-Earth asteroid that is a type called a chondrite, essentially a stony body that has high silicate content and few metals. It is about 330 meters across, and it's due to pass the Earth in 2029."

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How do they know the content by G3ckoG33k · 2011-01-31 06:26 · Score: 1

"it's a near-Earth asteroid that is a type called a chondrite, essentially a stony body that has high silicate content and few metals."
Hmmm. How do they know the content so well. I can understand long distance analyses of planet atmospheres and stars, but this piece of... err chondrite?
1. Re:How do they know the content by sensei+moreh · 2011-01-31 06:29 · Score: 3, Informative
  
  Spectroscopes
  
  --
  Geology - it's not rocket science; it's rock science
2. Re:How do they know the content by mangu · 2011-01-31 06:29 · Score: 2
  
  How do they know the content so well
  They know it by inference, from meteorites that have been recovered on earth and, presumably, have a similar composition.
3. Re:How do they know the content by Nadaka · 2011-01-31 06:31 · Score: 2
  
  Because its orbital properties have been very well studied due to the potential if civilization altering impact. We know its approximate volume and mass. this gives us a fairly good clue about its composition because a mostly metal asteroid would be much more dense.
4. Re:How do they know the content by Nyeerrmm · 2011-01-31 06:44 · Score: 4, Informative
  
  We have a good idea of the composition of asteroids in general, from meteorites, planetary formation models, etc.
  We believe Apophis is chondritic because based on its apparent brightness and the way that brightness varies, we have a decent estimate of its size and albedo. If it had a different albedo it would indicate a different composition.
  Of course, as with all remote observations based on a lot of educated guesses, there is a chance its wrong. However, if it is its probably a pathological case we could never gotten right, and that would make it even more interesting to visit.
5. Re:How do they know the content by sznupi · 2011-01-31 06:44 · Score: 1
  
  Not really, no. Not only we don't know its orbital properties to desired levels - simply knowing orbit won't really give you a very good mass of some point body, you need to observe a satellite of said body.
  
  Volume / size and mass are usually estimated from brightness and spectroscopy (comparing the latter with samples we have on Earth)
  
  --
  One that hath name thou can not otter
6. Re:How do they know the content by kikito · 2011-01-31 06:46 · Score: 1
  
  It was privately revealed to professor Huxdane that the asteroid was a chrondrite.
  http://www.youtube.com/watch?v=iV2VjdpVonY
7. Re:How do they know the content by The+Grim+Reefer2 · 2011-01-31 07:40 · Score: 1
  
  We have a good idea of the composition of asteroids in general, from meteorites, planetary formation models, etc.
  We believe Apophis is chondritic because based on its apparent brightness and the way that brightness varies, we have a decent estimate of its size and albedo. If it had a different albedo it would indicate a different composition.
  Of course, as with all remote observations based on a lot of educated guesses, there is a chance its wrong.
  In other words, SWAG (Scientific Wild Ass Guess)
8. Re:How do they know the content by Teancum · 2011-01-31 08:19 · Score: 2
  
  It is a little better than a wild ass guess. This particular asteroid happens to pass fairly close to the Earth from time to time and is also studied a bit more carefully due to its predicted potential to strike the Earth.
  Yes, there is a chance it could be wrong, but there have been other asteroids which have been studied much more carefully and have even had physical probes go near or even land upon them for various kinds of scientific studies. Based upon those studies as well as meteor samples it seems like a pretty good assumption.
  The orbital trajectory is known to a high degree, and it certainly will be passing near the Earth... at least pass closer to the Earth than the Moon is from us. A manned expedition to this asteroid is even possible under those circumstances, and certainly a sample/return mission could be possible not to mention having dozens of amateur and professional telescopes get a real close look at this object when it passes under the orbits of a whole bunch of satellites.
  What is especially useful here is due to this sort of close observation, it can help to refine and confirm or deny theories used to identify the composition of more distant asteroids. More likely it will help to refine them and perhaps even set up additional and finer classification guidelines.
9. Re:How do they know the content by Anonymous Coward · 2011-01-31 08:37 · Score: 1
  
  spectrography (AKA: Spectroscopy, Spectrometry, Spectroscopes) is definitely part of it. The orbit also gives them an idea of the mass of the asteroid which helps confirm that they the surface materials aren't too dissimilar to the inner makeup (because spectography can only detect the surface composition). Then they use examples of similar asteroids that have fallen to earth (I know "meteoroids") to refine the guesstimate on the makup a bit further. The only thing they can't make and educated guess on yet is whether they're looking at a rubble pile or a solid asteroid, I think the mass gives them somewhat of an idea, but its still shaky.
And that's the way it is... by OlRickDawson · 2011-01-31 06:27 · Score: 1

Closing remarks from Walter Chrondite, after reporting on the asteroid flyby...

--
Ol' Rick Dawson had a farm EIEIO
Not too much of a difference... by sznupi · 2011-01-31 06:28 · Score: 4, Informative

The speed, relative to Earth, during the encounter will be quite high - so a probe / lander / etc. allowing for really close study would need to get quite a kick from its rocket. And very rapidly (basically ruling out more efficient means of propulsion, those tend to have very low thrust) Probably much larger than sending it to some more optimal (regarding transfer orbits and delta-v) targets, a thing ... which we are already doing!

If it turns to be practical, another nice target is good to have of course.

--
One that hath name thou can not otter
1. Re:Not too much of a difference... by Locke2005 · 2011-01-31 06:37 · Score: 1
  
  Send up 3 rockets tethered together by cables meeting at a common midpoint into the path of the asteroid. Boom, asteroid hits cable, probes get accelerated by asteroid to matching speed and are dragged off being the asteroid, providing observations for a long time... what could possibly go wrong?
  
  --
  I've abandoned my search for truth; now I'm just looking for some useful delusions.
2. Re:Not too much of a difference... by mangu · 2011-01-31 06:41 · Score: 2
  
  The speed, relative to Earth, during the encounter will be quite high - so a probe / lander / etc. allowing for really close study would need to get quite a kick from its rocket
  It would probably be done in a roundabout way, first sending the probe in an interplanetary trajectory, to get gravitational assist from another planet. Then it would do a close fly-by to the moon to get the required orbit inclination.
  TFA states that the mission would have to be launched in 2021 to reach it by 2029.
3. Re:Not too much of a difference... by sznupi · 2011-01-31 06:51 · Score: 1
  
  Which in the end means that the goal of reaching it during flyby is quite ... irrelevant. We might "just" treat it as another very interesting near-Earth object, to be closely studied not necessarily starting from 2029 (hey, it would be of course great if we could get the funding and the mission reaching it even sooner!) - one which does have higher priority due to its risks (and how a beacon on its surface could be useful), but again: nothing too special about the encounter.
  
  --
  One that hath name thou can not otter
4. Re:Not too much of a difference... by commodore6502 · 2011-01-31 06:54 · Score: 1
  
  We really need to get off our butts, and invent Antimatter-powered warp drive.
  Oh wait. No antimatter. Never mind.
  
  --
  Information wants to be expensive AND wants to be free. So you have Value vs. Cheap distribution fighting each other.
5. Re:Not too much of a difference... by Just_Say_Duhhh · 2011-01-31 06:57 · Score: 3, Funny
  
  Would those be African or European rockets?
  
  --
  I need trepanation like I need a hole in the head.
6. Re:Not too much of a difference... by sznupi · 2011-01-31 07:04 · Score: 1
  
  Possibly no warp drive, too
  
  (but you might start by building a ship with a hull not constrained by Archimedes' principle ... its over 2 thousand years old, surely should be easier to ignore; those airplanes from "our" times, depicted in works of fiction from mere ~130 years ago, shouldn't be too far away now, too - because reality is just too boring)
  
  --
  One that hath name thou can not otter
7. Re:Not too much of a difference... by Rolgar · 2011-01-31 07:20 · Score: 1
  
  I think it would be much better to launch the probe prior to the approach of the rock, and let the rock catch up to it from behind. That or figure out a way to use the moon and Earth to slingshot a probe up to the necessary speed (I suppose if this we possible, we'd do it for every launch we currently make).
8. Re:Not too much of a difference... by Crudely_Indecent · 2011-01-31 07:27 · Score: 1
  
  Boom...
  ACME rockets?
  So, Mr Coyote, will you be using roller skates or a giant slingshot in that plan?
  
  --
  
  "Lame" - Galaxar
9. Re:Not too much of a difference... by jeffb+(2.718) · 2011-01-31 07:32 · Score: 1
  
  Tell me more about the material from which these cables are made.
10. Re:Not too much of a difference... by mikael · 2011-01-31 07:39 · Score: 1
  
  The asteroid isn't simply one big rock - it seems to be a orbiting pile of rubble that has coalesced into a single object. The cables would probably just cut straight through - though they might snag on one of the larger rocks (50m radius) and apply some force onto it.
  
  --
  Vintage computer adverts: http://www.vintageadbrowser.com/computers-and-software-ads
11. Re:Not too much of a difference... by srmalloy · 2011-01-31 07:59 · Score: 1
  
  Have you ever watched video of a bola being used to take down game? The weights at the ends of the cords whip around at increasing speed as they wind around the legs of the target. The average orbital velocity of Apophis is 30 kilometers a second, so that's the relative speed between the probes and Apophis when it hits the cables. If you ever played tetherball as a kid, you'll remember that the ball speeds up as it winds in to the pole, so the probes might well double the initial relative velocity by the time of impact; rather than "providing observations for a long time", what you'd be doing is performing the experiment "What happens when we hit Apophis with three probes at a relative velocity of 100,000 miles per hour?" That is, of course, assuming that you managed to produce a cable strong enough that it doesn't break on contact, and the acceleration as the probes wind in doesn't exceed their design limits.
12. Re:Not too much of a difference... by mangu · 2011-01-31 08:01 · Score: 1
  
  Would those be African or European rockets?
  Most probably European.
  African rockets never really took off.
13. Re:Not too much of a difference... by mangu · 2011-01-31 08:10 · Score: 2
  
  Although "The Relativity of Wrong" is one of my favorite Asimov essays, i wouldn't rule some changes in basic physics yet.
  The situation now is very similar to that in the second half of the nineteenth century. Then there existed a strong consensus that Newtonian physics were the last theory, but two facts spelled problems against that view: the inability to reconcile Maxwell's equations with Newtonian physics and the Michelson-Morley experiment.
  Today we have some facts that give some hint that relativity presents some problems: the Bell inequality, the Pioneer anomaly, the galaxy rotation problem.
  Looking at the different explanations for the Pioneer anomaly I feel a strange sense of deja-vu, because they sound a lot like the explanations for the Michelson-Morley experiment in the late 1800s. Same thing with the theories invented to reconcile GR with QM.
14. Re:Not too much of a difference... by Gilmoure · 2011-01-31 08:36 · Score: 1
  
  What if the cord was a really strong bungie?
  
  --
  I drank what? -- Socrates
15. Re:Not too much of a difference... by sznupi · 2011-01-31 08:47 · Score: 1
  
  Do not forget to mention how, if anything, the realization of the consequences of Michelson-Morley experiment (and also the then triumphant wave theory hitting some dualities) had shown also many further limits of our world. And those effects were, ultimately, quite large.
  
  If the Pioneer anomaly exists, it's exceedingly minuscule. Sensible proportions of dark matter and dark energy dictated by cosmological models ... surprisingly in line with those suggested by observations. Or, one of my favorites: how inertia appears to act like a gravitational influence from the rest of the Universe ... but this has a major headache of, for one example, requiring the interaction to go backwards in time! Couple it with how the Universe doesn't appear to have signs of expansive intelligence which developed (that's almost equivalent to "will ever develop"!) FTL / time travel - and I wouldn't be too surprised if our speed of light limit will turn out to be even more fundamental than we thought. Or, to put it another way, maybe so ingrained into other basics, that trying to work around it doesn't matter - the relative values, properties and character remaining similarly limited for all sensible Universes.
  
  Don't get me wrong - escaping our constraints would be great. But wishful thinking certainly has its limits.
  
  --
  One that hath name thou can not otter
16. Re:Not too much of a difference... by sznupi · 2011-01-31 08:54 · Score: 1
  
  As I said, quite a kick (one of more powerful rockets used, fairly small probe) - plus it's much closer (possibly not enough, you would need to do calculations) than it looks; that escape velocity of New Horizons doesn't include how, with Apophis approach, effects which often are used to ease getting into orbit, might get in our way; or change of orbital inclination around the Sun. Plus exceptionally small launch window.
  
  --
  One that hath name thou can not otter
17. Re:Not too much of a difference... by sznupi · 2011-01-31 09:03 · Score: 1
  
  That's not "letting the rock catch up to it from behind", that's "letting the rock pass it, quite rapidly". And you cannot slingshot via body around which you are orbiting, that in itself requires already relatively fast passes / what we're doing with pretty much every interplanetary probe (also using Earth, but as, for one hypothetical example: 1) launch from Earth 2) slingshot during Venus flyby 3) second Venus slingshot 4) Earth slingshot 5) Jupiter slingshot 6) ... )
  
  --
  One that hath name thou can not otter
18. Re:Not too much of a difference... by mangu · 2011-01-31 09:20 · Score: 1
  
  I think the speed of light limitation is very fundamental, based on mathematics alone: IF space and time are quantized, the Courant condition will not let waves propagate faster than a certain speed.
  Nevertheless, a universe with FTL would be much more interesting...
19. Re:Not too much of a difference... by CrimsonAvenger · 2011-01-31 09:36 · Score: 1
  
  The speed, relative to Earth, during the encounter will be quite high
  The speed, relative to Earth, during the encounter will be similar to the speed Apollo had after it's lunar injection burn. Rather less than the speed required to send something to Mars.
  In other words, not really a big deal, compared to things we've already sent into space.
  
  --
  
  "I do not agree with what you say, but I will defend to the death your right to say it"
20. Re:Not too much of a difference... by sznupi · 2011-01-31 10:13 · Score: 1
  
  I never really considered OTRAG to be African... certainly no more than Ariane 5 being South American (or Soyuz - Asian). Too bad it didn't even really get a chance..
  
  And hopefully no more of
  
  Nkoloso, at least from the evidence we have to go on, was something closer to a cargo cult leader than a scientist. What remains fascinating to us today is that he drew on the sublimity of space travel -- not religious sentiment -- to win friends and influence people. It's a reminder of the power that space travel had in the popular imagination of the 1960s.
  ( Old, Weird Tech: The Zambian Space Cult of the 1960s
  Edward Makuka Nkoloso )
  Though I seriously wonder about the mentioned cats ;) ... if we ever seriously venture into space, what other cuddly pet could be possibly better? ;p (not only agility or hygiene, also the theme of them being chosen already when the space is scarce and conditions hard ... )
  
  --
  One that hath name thou can not otter
21. Re:Not too much of a difference... by Lanteran · 2011-01-31 15:53 · Score: 1
  
  For interplanetary distances, a 20 Megawatt fission reactor powering a VASIMR engine is all you'd really need. As for interstellar distances, a slow nuclear-pulse orion-type ship would be the best investment. For some reason, I suspect *effective* FTL (e.g. not actually going the speed of light- side stepping it, such as a worm hole) is possible, but it is much further away then sub-light and near-light interstellars.
  
  --
  "People don't want to learn linux" hasn't been a valid excuse since '03.
22. Re:Not too much of a difference... by sznupi · 2011-01-31 16:47 · Score: 1
  
  Most Orion design studies were about interplanetary travels. Orion is barely able to do "fun" interstellar - the most advanced designs limited to ~0.1c, in the range of a human lifetime to the nearest stars. But expect few of those lifetimes.
  
  If we ever try direct approach - the colonists might be miniaturized and in deep hibernation (we can already do that last dream!). IMHO most likely just spreading gradually, over thousands of years, further and further into the Oort cloud (estimated one trillion comets; there's really no reason to go to some random, almost certainly completely uninhabitable, inner system) ... until some groups will hitch a ride via the cloud of some passing star. That will still allow us to colonize the galaxy very rapidly, in geological scale.
  
  And don't expect wishful thinking from works of fiction to come true.
  
  --
  One that hath name thou can not otter
23. Re:Not too much of a difference... by sznupi · 2011-01-31 16:52 · Score: 1
  
  Did our recent impactor of a comet (which also seem to be largely a case of rubble pile, but even finer...) flew through it?
  
  --
  One that hath name thou can not otter
24. Re:Not too much of a difference... by toddestan · 2011-02-01 14:11 · Score: 1
  
  That would slow the asteroid down ever so slightly. If the next time around, the asteroid ends up slamming into the Earth, we're all going to blame you.
25. Re:Not too much of a difference... by toddestan · 2011-02-01 14:28 · Score: 1
  
  I don't see the fundamental problem with launching a probe well beforehand, and then using a slower drive or various tricks in order to bring it up to the required speed over a period of time. However, I suppose then you're not really taking advantage of the asteroid coming so close to Earth either.
26. Re:Not too much of a difference... by Lanteran · 2011-02-01 14:45 · Score: 1
  
  I know about the general 0.1c speed limit- honestly, I think it's fast enough to be practical when compared with the multi-millennial travel times of conventional rockets. If you did put the colonists in stasis, it's a decently fast way of headed to the stars. I've always thought that slow STL (that is, below 5% c or so) colonization plans were a waste of resources- even if you can mine from say an asteroid you're riding there. Nothing's wrong with slow interstellar colonization, ala firefly, but ideally we should spread rather quickly.
  
  --
  "People don't want to learn linux" hasn't been a valid excuse since '03.
27. Re:Not too much of a difference... by sznupi · 2011-02-09 00:13 · Score: 1
  
  I think it doesn't make much difference. What is "ideally" and why would it matter? Once some homo sapiens are in a different system than you, they are almost as well as nonexistent (recollect the relations of distant human populations before the Age of Discovery, before suitable vessels... which most likely won't ever become available for interstellar; similar thing, to a large degree, would happen even with outer planets of our system - not to mention scattered disk or Oort cloud), except for some (why would they waste resources on hellishly powerful transmitters?) amount of exchanged data, a scientific curiosity.
  
  So why would you direct half the GDP of your system for their mission? What about that as far as waste of resources goes? Was there ever a society which funded such expensive exploration even when expecting results / gold / etc.? What about - when expecting no returns at all? (apart from "oh, that's curious" results)
  
  OTOH, slow Orion of "interplanetary" type (or reactor + electric propulsion; or beamed power sail; whatever), carrying virtually all (at least) colonists microscopic & in stasis, seems affordable enough... As far as the other plausible IMHO method - I don't mean riding an asteroid or comet, just hopping. That would still be a rather quick spread, in geological terms. Speedups from "faster" methods would barely register (considering a much more developed & united industry necessary for sending such vessels)
  
  --
  One that hath name thou can not otter
28. Re:Not too much of a difference... by sznupi · 2011-02-09 00:22 · Score: 1
  
  ...and the probe at some early point in "bringing up to speed" would be even no longer orbiting the Earth.
  
  --
  One that hath name thou can not otter
29. Re:Not too much of a difference... by Lanteran · 2011-02-09 13:32 · Score: 1
  
  I get your arguments, and agree with most of it about resource waste for conventional manufacturing techniques. The embryonic ships also always seemed a good idea to me. But as far as the interstellar class orions, I think you're underestimating advances in the next hundred years or so. Picture it from a perspective into the fairly long term future, with a manufacturing system completely restructured by nanotechnology. Your ship fires a capsule of nanites into an asteroid or comet with the suitable resources, and within a few weeks or maybe months (assuming self replication) they've assembled a ship from molecular raw materials, fully fueled. Kind of like a controlled grey goo scenario on a smaller scale. With manufacturing costs lowered significantly, the main cost barrier drops, and large scale 50 year caravans to interstellar space become feasible. Not to even mention if it ever becomes possible to store stable antimatter- an antimatter powered orion could approach 80-90% of the speed of light. That's a decade or less flight time to nearby stars, accounting for acceleration-deceleration times- very well within range for large scale colonization of the galaxy.
  
  --
  "People don't want to learn linux" hasn't been a valid excuse since '03.
Capture it! by smoothnorman · 2011-01-31 06:36 · Score: 2

As a proof of concept of the manipulation of large nearby objects for commercial or planetary defense why not attempt to capture it into some not too remote orbit? I mean, "what could possibly go wrong?" Think of it as keeping a cue-ball handy for the next object that we want to redirect. Or stick telemetry on it; or a kick-ass telescope. Or mine it for unobtainium. If we don't learn to screw with the toys nearby we'll never move on to the proper human hegemony.
1. Re:Capture it! by ddd0004 · 2011-01-31 06:47 · Score: 2
  
  We could also move it into a low earth orbit and use it to sweep paths through all the obsolete satellites and other space junk that is up there. Maybe sell the naming and advertising rights to the highest bidder too. I personally look forward to watching the Cialis Erectoid flying overhead.
2. Re:Capture it! by Covalent · 2011-01-31 06:59 · Score: 4, Informative
  
  Hard to do! It's speed is about 31 km/s...geosynchronous orbit is more like 3 km/s. So delta V is about 28km/s...for an asteroid with a mass of 2.7×10^10 kg, that's a kinetic energy of about 1E19 J or around 2.5 billion tons of TNT (2.5 gigatons). Yeah...that's a lot.
  
  --
  Great warrior...hrmph! Wars not make one great.
3. Re:Capture it! by wall0645 · 2011-01-31 07:13 · Score: 1
  
  One of the reasons we would not want to do this (change the path of the asteroid), as Carl Sagan talked about (I believe in the COSMOS TV series), is because if we could, it means we would also have the technology to direct the course of the asteroid into the Earth. I'm not sure if this is the only reason we have not yet tried such a thing (perhaps we've just never had such an opportunity), but I think some are hesitant to explore this potential doomsday weapon.
4. Re:Capture it! by sznupi · 2011-01-31 07:31 · Score: 1
  
  You want to provide a large, loosely held target, guaranteed to be hit by lots of the projectiles (and many good satellites...) which are already there? Brilliant...
  
  --
  One that hath name thou can not otter
5. Re:Capture it! by khallow · 2011-01-31 07:34 · Score: 2
  
  One of the reasons we would not want to do this (change the path of the asteroid), as Carl Sagan talked about (I believe in the COSMOS TV series), is because if we could, it means we would also have the technology to direct the course of the asteroid into the Earth. I'm not sure if this is the only reason we have not yet tried such a thing (perhaps we've just never had such an opportunity), but I think some are hesitant to explore this potential doomsday weapon.
  Yes, if we don't do it, then we'll never figure out that we can do it... wait...
6. Re:Capture it! by sznupi · 2011-01-31 07:35 · Score: 1
  
  Yeah, just another fantasy ... it's no wonder people are disappointed, after all the works of fiction they're attacked with, by our great achievements in space.
  
  Well, there might be one doable mechanism - transfer of momentum to capture one element of binary asteroid. Still far from trivial, especially if such object needs to be redirected (because there doesn't seem to be one readily available). And for doubtful gains.
  
  --
  One that hath name thou can not otter
7. Re:Capture it! by atrain728 · 2011-01-31 08:24 · Score: 1
  
  It's orbital velocity may be near 31 km/s (relative to the sun), however it's velocity relative to earth (which would be the figure you're citing for geosynch orbital velocity) is not that great. Earth's orbital velocity is about 1 km/s lower than that. Of course, you can't say that the relative velocity between the two is the difference since this is quite obviously a 3 dimensional problem.
  
  However, you can say that this is within the range of velocity of a geosynch satellite (30km/s +/- 3km/s) relative to the sun.
  
  I'll leave the orbital mechanics to the astrophysicists, but from what I've read - especially given opportunity of the slingshot event in 2029 - it seems entirely plausible that a cluster of ion/VASIMR thrusters could alter the trajectory enough such that the 2029 event would be a capture, rather than a near miss.
8. Re:Capture it! by Gilmoure · 2011-01-31 08:38 · Score: 1
  
  If you could deflect it towards the atmosphere and then aerobrake it in to a circular orbit around the Earth...
  Might be better to try this with the Moon.
  
  --
  I drank what? -- Socrates
9. Re:Capture it! by Anonymous Coward · 2011-01-31 08:58 · Score: 1
  
  If you could deflect it towards the atmosphere and then aerobrake it in to a circular orbit around the Earth...
  Might be better to try this with the Moon.
  I don't think we should try to aerobrake the moon.
10. Re:Capture it! by Gilmoure · 2011-01-31 09:08 · Score: 1
  
  :-P
  
  --
  I drank what? -- Socrates
11. Re:Capture it! by rahvin112 · 2011-01-31 09:41 · Score: 1
  
  Well, we do have something like 50,000 nuclear warheads we (hopefully) don't ever plan on using. At an average yield of about 400MegaTons each we should have enough as long as everything is planned and the blasts are as focused as possible. How about we land a shuttle on the asteroid, drill a shaft to act as focus for the blast energy, then set off several weapons from within the asteroid to redirect it's path. Maybe we can hire Bruce Willis do to the drilling!
12. Re:Capture it! by karlwilson · 2011-01-31 10:07 · Score: 1
  
  Except, when you move an object into a specific orbit, it moves at the same speed as everything else in that orbit.
13. Re:Capture it! by WildBlueYonder · 2011-01-31 12:35 · Score: 1
  
  I'll leave the orbital mechanics to the astrophysicists.
  I'll take a shot at it.
  While you are right in saying that their orbital speeds are very close, that doesn't necessarilly mean that their velocities will be that close together. Even when you are just working in 2 dimensions the difference in speed between 30 km/s and 31 km/s could lead to a difference in velocity from 1 to 61 km/sec.
  In addition that just gives you the V-inifinite, or the velocity when the mechanics switch over to predominantly be a two body problem between the asteroid and the Earth instead of a two-body problem between the Asteroid and the sun. At this point the asteroid has maximum potential energy. As the asteroid approaches the Earth it will continue to speed up until it is as close as it is going to get, at which point the relative velocities will be at their highest. As the asteroid leaves Earth's influence it will once again reach the speed of V-inf with respect to Earth, although it's speed with respect to the rest of the solar system will have changed. That's the basis of a slingshot maneuver.
  Anyways, the Impact Risk Summary that the Near Earth Orbit Program made back in October 2009 estimated a V-infinity of 5.87 km/s and an impact velocity of 12.59 km/sec. The latest estimates have V-inf at 5.84 km/sec and the maximum relative speed at 7.42 km/s.
  Let's say that we need 5 km/s to capture Apophis in our desired orbit. With a specific impulse of 450 s (similar to the space shuttle main engines) we'd need more than 3 times the mass of Apophis in propellant. Apophis has a mass of 2.7E10kg. We'd need more than 3 million space shuttle missions to lift all the propellant into lower-earth orbit.
14. Re:Capture it! by paulzeye · 2011-01-31 13:08 · Score: 1
  
  That is a lot of energy, but we do have 19 years. Some kind of long slow power source would help make more feasible but maybe 19 years still isn't enough.
15. Re:Capture it! by mikael · 2011-02-01 06:36 · Score: 1
  
  We could always launch a heavy chunk of metal in a sling-shot orbit towards the Sun and have it hit Earth several months later.
  
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16. Re:Capture it! by eriqk · 2011-02-01 10:19 · Score: 1
  
  If you could deflect it towards the atmosphere and then aerobrake it in to a circular orbit around the Earth...
  Might be better to try this with the Moon.
  Aerobraking around the Moon might prove to be somewhat problematic.
i'm taking bets now by circletimessquare · 2011-01-31 06:39 · Score: 1

that if we land on it or sample it or crash something into it, it will perturb the orbit just enough to hit us at some point

--
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1. Re:i'm taking bets now by bunratty · 2011-01-31 07:12 · Score: 1
  
  Don't worry. The Earth has survived plenty of asteroid impacts in the past. Therefore I conclude that asteroid impacts are nothing to worry about.
  
  --
  What a fool believes, he sees, no wise man has the power to reason away.
2. Re:i'm taking bets now by ddd0004 · 2011-01-31 07:53 · Score: 1
  
  Sounds good to me. Have you considered running for office?
3. Re:i'm taking bets now by markwalt · 2011-01-31 09:03 · Score: 1
  
  Yeah, Earth has survived it reasonably well. Her flora and fauna, however, have a mixed record with respect to impact survival.
4. Re:i'm taking bets now by Last_Available_Usern · 2011-01-31 09:07 · Score: 1
  
  Ok, put me down for $8bil that it doesn't hit. I'll let my great x 10^37 grandchildren settle up this wager.
Cool! by Pro923 · 2011-01-31 06:40 · Score: 1

Let's mess with it and change it's gravity slightly!
1. Re:Cool! by Nyeerrmm · 2011-01-31 06:54 · Score: 1
  
  Those analyses are relatively easy to do, and you're not going to change its trajectory significantly unless you really mean to.
  In order to do it with a ~500 kg spacecraft you have to hover about 200 meters away from the asteroid with your engines thrusting essentially continuously for around a year. If you're not close enough to have to worry about hovering, or if you're trying to do a landing, no reasonably sized spacecraft is going to make a difference.
2. Re:Cool! by Pro923 · 2011-01-31 07:08 · Score: 1
  
  In my mind, at a distance the mass of an object would include things that are in orbit around it - in terms of how it interacts with things far away gravitationally. Whether or not this adds up to anything significant over the course of the object's millions of miles of orbit - I'll give you that I could imagine that the difference is insignificant.
3. Re:Cool! by Nyeerrmm · 2011-01-31 07:17 · Score: 1
  
  Well, as long as the mass of the object is negligible compared to the body its orbiting (in this case, the asteroid is absurdly smaller than the sun), then the mass of the body has no effect on its orbit. More specifically, the force is proportional to the mass so that the acceleration is constant regardless of mass.
  The only time it will make a difference is for non-gravitational forces like solar radiation pressure or atmospheric drag. Then the surface area of the spacecraft will be much smaller than the asteroid, so it won't be a big deal, unless you're trying to change it on purpose.
  Also, you never want to try and orbit a small asteroid like this. Their gravity fields are way too weird and unpredictable and you can end up crashing after a few revs of what starts out looking stable. Preferably you either land, get far enough away that the gravity is just a perturbing force, or do the standoff required for gravity tractoring.
Apophis? by Locke2005 · 2011-01-31 06:40 · Score: 2

What's with the exotic asteroid names? Just once, I'd love to see them name an extraterrestrial body "Bob". I can see the headlines now: "Bob threatens impact with Earth". Much less scary than "Apophis threatens to wipe out all life on planet!".

--
I've abandoned my search for truth; now I'm just looking for some useful delusions.
1. Re:Apophis? by sconeu · 2011-01-31 06:45 · Score: 1
  
  I'm just waiting for the one named "Anubis", or even "Ori".
  Of course, if you want a vaguely threatening "ordinary" name, try "Todd".
  
  --
  General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
2. Re:Apophis? by ceoyoyo · 2011-01-31 06:46 · Score: 1
  
  I didn't see a straight Bob, but there are BobBell, BobbieVaile, BobbyWilliams, BobGent, BobHawkes, BobHope, BobOne and BobRoss.
3. Re:Apophis? by Luthwyhn · 2011-01-31 07:06 · Score: 2
  
  Asteroid Bob Ross? I can see it now... what a happy little impact crater!
4. Re:Apophis? by Chapter80 · 2011-01-31 07:11 · Score: 1
  
  What's with the exotic asteroid names? Just once, I'd love to see them name an extraterrestrial body "Bob". I can see the headlines now: "Bob threatens impact with Earth". Much less scary than "Apophis threatens to wipe out all life on planet!".
  Hurricanes (and Storms) have that feature.
  Given that my name is one of the chosen Storm names (but it's not Bob), I am not sure if I would prefer to have a headline that said "Bob Kills 30,000, Leaves Millions Homeless" or "Bob is a Dud"
5. Re:Apophis? by Compholio · 2011-01-31 07:28 · Score: 1
  
  Much less scary than "Apophis threatens to wipe out all life on planet!".
  Rumor is that the guys who originally spotted it named it after the Stargate SG-1 character, who (presumably) sent an asteroid to destroy the earth in the episode "Fail Safe."
6. Re:Apophis? by wolverine1999 · 2011-01-31 07:51 · Score: 1
  
  That's precisely what I thought when I read this....
  
  --
  SCIREV.NET - fanfics,reviews & more
7. Re:Apophis? by BitZtream · 2011-01-31 07:56 · Score: 1
  
  You've clearly never watched Stargate SG-1.
  Apophis has tried to wipe out life on Earth on multiple occasions, though someone else tried to do it by throwing an asteroid at us.
  From a sci-fi perspective, Apophis is a perfect name :)
  
  --
  Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
8. Re:Apophis? by Cro+Magnon · 2011-01-31 08:40 · Score: 1
  
  Yeah, as soon as I saw the name of the asteroid, I got a mental image of MacGuyver complaining that he could see his house from it.
  
  --
  Slow down, cowboy! It has been 4 hours since you last posted. You must wait another few hours.
9. Re:Apophis? by Teancum · 2011-01-31 08:54 · Score: 1
  
  By way of Wikipedia, this article on Astronomy.com seems to point out that indeed the connection to SG-1 is there in terms of how this asteroid was named.
  It is sort of ironic too as there was an episode of SG-1 that dealt with an asteroid that was purposely deflected to hit the Earth by that Goa'uld system lord of the same name. That the mythology of the Egyptian god fits so well and the name up to that point had not been previously used on an asteroid only made it a perfect fit. It certainly isn't a name that would upset the IAU as much as 2309 Mr. Spock did at the time it was named. BTW, that particular asteroid was named after a pet cat and not the Star Trek character.
10. Re:Apophis? by pastyM · 2011-01-31 10:24 · Score: 1
  
  Oh, I so wish I had mod points.
11. Re:Apophis? by ColdWetDog · 2011-01-31 15:05 · Score: 1
  
  Would you like one of mine?
  
  .
  
  --
  Faster! Faster! Faster would be better!
12. Re:Apophis? by isilrion · 2011-01-31 16:40 · Score: 1
  
  Much less scary than "Apophis threatens to wipe out all life on planet!".
  Rumor is that the guys who originally spotted it named it after the Stargate SG-1 character, who (presumably) sent an asteroid to destroy the earth in the episode "Fail Safe."
  Actually, that was Anubis. Apophis died a few episodes earlier.
13. Re:Apophis? by IHateEverybody · 2011-01-31 17:20 · Score: 1
  
  What's with the exotic asteroid names? Just once, I'd love to see them name an extraterrestrial body "Bob". I can see the headlines now: "Bob threatens impact with Earth". Much less scary than "Apophis threatens to wipe out all life on planet!".
  I like this idea. It opens up so many possibilities for impact remediation mission names. For example, Cometary and asteroidal Orbital adjustment Under Controlled Hazards (COUCH). I'm already picturing the headline: Scientists prepare COUCH for Bob to crash on.
  
  --
  Does this .sig make my butt look big?
due to pass by confused+one · 2011-01-31 06:41 · Score: 2

*nudge* There, fixed that for ya. Now it'll land so you can get a closer look...
Re:If the eyes start glowing by commodore6502 · 2011-01-31 06:45 · Score: 2

I love that show (Stargate). Not as good as Babylon 5 or Deep Space Nine, but still a great series. Always kept me on the edge of my seat, and I enjoyed the "exploring new worlds" aspect that other shows have abandoned.
- Like the planet with the strange white men that talked to flowers
- Or the time they accidentally opened onto a black hole gate (Never understood why they were not able to rescue the other SG team.)
- Or the first time they met the replicators
Good stuff.

--
Information wants to be expensive AND wants to be free. So you have Value vs. Cheap distribution fighting each other.
Re:If the eyes start glowing by NoEvidenZ · 2011-01-31 06:47 · Score: 2

Apophis? No problem. If it had been called Anubis I would've been worried that it was filled with Naquadah or something.
We can handle this by SnarfQuest · 2011-01-31 06:49 · Score: 1

We already know how to deal with asteroids. But do we have enough sharks?

--
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
If only it were made of gold! by CCTalbert · 2011-01-31 06:59 · Score: 1

Or platinum, etc.... Then there'd be waaaay more interest. The Chinese would announce they were going to land on it, then everyone else would have to jump on the bandwagon. Silica? yawn......
Maybe if we're lucky we'll see a monolith on it as it passes.
Apt description by nigelo · 2011-01-31 07:07 · Score: 1

...essentially a stony body that has high silicate content and few metals.
Hm, with advancing years and dealing with four sons, I rather resemble that remark...

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*Still* negative function...
Re:it's due to pass the Earth in 2029 by AndrewNeo · 2011-01-31 07:23 · Score: 1

Are you asking if it's metric 2029 or imperial 2029?
A moot point by nilbog · 2011-01-31 07:30 · Score: 1

A moot point as the world will end in 2012. But maybe if the reptilians are able to come to the surface and learn our technology they will be able to pick up where we left off and study the astroid.

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or else!
Neil DeGrasse Tyson on Apophis by RelliK · 2011-01-31 07:38 · Score: 1

http://www.youtube.com/watch?v=xaW4Ol3_M1o

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___
If you think big enough, you'll never have to do it.
Nice planet ya got there... by SunSw0rd · 2011-01-31 07:46 · Score: 1

Since when is 20 years from now "soon"? On the other hand, if there are space pirates out there Apophis is just right to use for blackmail. "Nice planet ya got there, be too bad if anything happened to it!". Although there is the question of what we have that they they would want.
1. Re:Nice planet ya got there... by Robert+Zenz · 2011-01-31 09:31 · Score: 1
  
  If measured with a lifetime, 20 years is of course long. But if you look at it from an astronomical (or was it astrological?) point of view, you better shouldn't blink because you could miss it.
Soon? by dynamo · 2011-01-31 08:15 · Score: 1

Look, I know we're talking large time scales here, but the word 'soon' is not appropriate to use with a wait time of 18 years.
1. Re:Soon? by blair1q · 2011-01-31 09:31 · Score: 1
  
  Now subtract time to get the public's attention, time to direct that attention towards political action to fund a mission, time to arrange the prime contracts for the mission, time to design the system well enough to let subcontracts, time to develop the components, time to integrate the components, and time to launch the vehicle and travel to the asteroid.
  We'll probably miss it by 8 months.
asteroid retrieval by k6mfw · 2011-01-31 08:19 · Score: 1

I remember in late 1970s of looking through a NASA STAR reports abstracts, there were a series of reports on asteroid retrieval. I think it discussed these in terms of mining for various metals and I think of of these suggested placing an asteroid in earth orbit. One of these days I'll find that book (along with other archival stuff like my CB radio license). I did a quick search but didn't find these (yes I know I gotta make it specific but then if I can do that then I already have the reports!). I did see some listings mentioning space elevators and "Asteroid Retrieval by Rotary Rocket." Gotta get back to work anyway.

--
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bilbe code 2029 by Joe+The+Dragon · 2011-01-31 08:43 · Score: 1

bilbe code 2029
Re:If the eyes start glowing by smooth+wombat · 2011-01-31 08:45 · Score: 2

Or the time they accidentally opened onto a black hole gate (Never understood why they were not able to rescue the other SG team.)

Apparently you didn't like the show enough to understand why they couldn't rescue the other team. It had to do with the gravity well of the black hole causing time dilation. What they were seeing had already taken place.

In fact, the event horizon got into the SG center and was in the process of doing its thing until a small nuclear device was dropped into the Stargate, severing the connection.

The complete rundown.

--
We will bankrupt ourselves in the vain search for absolute security. -- Dwight D. Eisenhower
Don't miss this opportunity by aminorex · 2011-01-31 09:17 · Score: 1

Apophis is a great opportunity to put an asteroid in orbit. The technology would allow us to put high-value mining resources in easy reach of orbital platforms. The result would be vast mineral resources available for engineering works, without costly launch fuel requirements.

--
-I like my women like I like my tea: green-
1. Re:Don't miss this opportunity by kwbauer · 2011-01-31 11:04 · Score: 1
  
  High-value? Is silica really that hard to find on Earth?
2. Re:Don't miss this opportunity by orkysoft · 2011-01-31 14:03 · Score: 1
  
  No, but it is terribly expensive to get it into orbit.
  Of course, it'll also be terribly expensive to slow this asteroid down...
  
  --
  
  I suffer from attention surplus disorder.
and by "close study" they mean by commodoresloat · 2011-01-31 10:47 · Score: 1

revolving around slowly in a circle going "pew pew pew!" at it
Re:Extraterrestrial Warning from 1981 by Chris+Tucker · 2011-01-31 11:28 · Score: 1

That the same Billy Meier who got caught faking UFO sightings on film, via homemade models on a string? Who claims to have been in contact with aliens?
THAT Billy Meier?
You own a LOT of SCO stock, don't you?

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Yes, fine, but by ThatsNotPudding · 2011-02-01 00:49 · Score: 1

when do we start grabbing these suckers and start working on our mining techniques, ffs?