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New nuclear deflection simulations advance planetary defense against asteroids
- mnky9800n 3y agoWell that seems like a fun job.
- keyle 3y agoI was just thinking the same! Shooting rocks in space! If only someone made a game about this, 44 years ago :)
- Semaphor 3y agoAnd the picture is a woman looking very pleased and "yes, I always wanted to throw nuclear bombs at asteroids, and there’s nothing you can do about it!" :D
- spenczar5 3y agoI was at the Planetary Defense Conference when Dr Burkey presented this work. The previous talk had been on a detailed hydrodynamics simulation which measured characteristics of rubble-pile asteroids, run on a supercomputer. She started with something like “That was cute, wasn’t it? I am going to talk about our simulation of every photon during a nuclear detonation.” It was awesome.
- Vecr 3y agoI think one of the most important tasks for planetary defense is detecting comets and asteroids early. That's why I think continued funding of the SpaceX ultra-heavy lift booster is a good idea, not for any reason related to the moon or mars, but for the ability to ride-share cheaper and heavier space-based survey telescopes.
- deleted 3y ago[deleted]
- WendyTheWillow 3y ago[flagged]
- anu7df 3y agoI don't think in this use case that would be very logical. If we want to deploy survey telescopes and use SpaceX for it, what is the harm. Once deployed it is deployed. On the other hand if it was about deploying the nuclear deflection device through some SpaceX rocket I would be worried. I wouldn't be surprised if musk tried some destructive grand standing at the last moment derailing the whole thing and dooming us all.
- deleted 3y ago[deleted]
- j4yav 3y agoA simple video letter from every living human explaining how we think he's a really super cool and funny and handsome guy should get the ball rolling.
- WendyTheWillow 3y agoThe telescope in question was at one point the proposed Sentinel [0] (apparently now the NEO Surveyor [1]), and frankly, even for something like that, I simply don't trust Elon because of its purpose. SpaceX has a stench about it that calls into question everything they're involved in, so long as he's at the helm. Besides, given the low weight of 1,300kg, NASA is perfectly capable of launching the NEO Surveyor on its own via the SLS [2]. [0] https://en.wikipedia.org/wiki/Sentinel_Space_Telescope https://en.wikipedia.org/wiki/Sentinel_Space_Telescope [1] https://en.wikipedia.org/wiki/NEO_Surveyor https://en.wikipedia.org/wiki/NEO_Surveyor [2] https://en.wikipedia.org/wiki/Space_Launch_System https://en.wikipedia.org/wiki/Space_Launch_System
- asynchronous 3y agoYou’re holding it against him that he didn’t want Starlink used onboard physical weapons of war?
- deleted 3y ago[deleted]
- spenczar5 3y agoHonestly, with LSST coming online in the next few months, and NEO Surveyor on the way in the next decade, I think we are pretty set already for observational instruments. The big gap that I see is in software. (I work on asteroid detection for planetary defense professionally)
- 93po 3y agoWe've seemingly looked at so little of the universe though? Wouldn't more instruments be a good thing?
- hermitcrab 3y ago>I work on asteroid detection for planetary defense professionally Cool. I am a software engineer with nearly 40 years professional experience. I wondered if volunteering to work on an open source software related to planetary defense might be an interesting retirement project.
- preisschild 3y agoTime to unpack Gnomon and Sundial (10 Gigatons of TNT equivalent)
- the8472 3y agoThose are cooler in allcaps.
- sgt101 3y agoIf I were scratching up a way of doing this I think I would rather have 500 or 1000 smaller devices to use...
- arethuza 3y agoA Gnomon device would probably be a few hundred tons and a Sundial a few thousand tons - hence the delivery mechanism for the latter on Teller's blackboard apparently being "backyard": https://blog.nuclearsecrecy.com/2012/09/12/in-search-of-a-bigger-boom/ https://blog.nuclearsecrecy.com/2012/09/12/in-search-of-a-bi...
- the8472 3y agoWith modern nuclear weapons design they could probably be a lot lighter. Speculation has it that the US can now build fusion secondaries without the heavy pusher.
- HPsquared 3y agoAll well and good until a Bond villain gets control of the system. (Edit: although this is very unlikely, I guess)
- M95D 3y agoUnlikely like the uranium centrifuges in Iran?
- Aransentin 3y ago> very unlikely Actually, what are the chances of this system – if it existed – is used to move an asteroid into the path of the Earth and killing everybody within the next 100 years? (This would include scenarios like "the US president or industrialist who builds it randomly goes insane"). 1%? 0.1%? If the risk of an asteroid hitting the earth is lower than that we should clearly not build such capability.
- HPsquared 3y agoAs long as it's possible, the insane ones might do it. We cannot allow an asteroid gap!
- totallyhuman 3y agoI imagine it would be possible to construct the system to substantially reduce the risk, even reduce it to "cosmic rays cause bit-flips which launch nukes" levels of risk. It's not like military nuclear command-and-control, you don't need one person who can push the button at any time. If we spot an asteroid, we'll have some time to deal with it. The system would presumably need to be constructed, which would take a few days even if everything was in storage on standby. Then, to activate it, you could have something like the US nuclear weapons' PAL, but instead of the codes being in the hands of one person, you spread them out. Just before launch it's activated with something analogous to the ICANN key ceremony: a bunch of well-regarded astronomers, rocket scientists, and aerospace engineers use their section of the Earth Asteroid Defence Key, and they press the metaphorical button together.
- skeaker 3y ago
- nicoboo 3y agoWe all have the biggest movie in mind and we know the unfortunate situation our heroe is facing right now, makes us all doomed. More seriously, interestingly, those analysis would require early detection and therefore investments on such approach, which might not be always the case. The article was interesting and I hope we won't be prototyping soon.
- neonsunset 3y agoHuh, why is there a technology unlock message from Stellaris in my HN feed? :)
- iAMkenough 3y agoLike some defense projects, I predict we'll outsource it to a private party, pay them public tax subsidies, and fail to hold them accountable when they go against our public defense interests.
- M95D 3y agoIn case of an asteroid, our interests are also theirs. OK, let's say they go against our interests. What are they going to do next? Move to Mars??
- bratbag 3y agoTheir interest is to convince themselves that it won't be needed in their lifetime, and to hell with anyone else after they are dead.
- leoedin 3y agoThis seems like the biggest failure point. Humans are basically unable to prepare for major but rare events (eg the pandemic response). Day to day politicing always wins, and when the problem is suddenly on top of us we've got nothing. I think the best we can hope for (apart from not having an asteroid heading our way at all) is that we'll have sufficient notice that something can be done. If we had a couple of years notice, there's a reasonable chance the deadline would be motivation enough to get something built.
- spenczar5 3y agoSo, this research is extremely cool. The way nuclear deflection works is not how you think. You probably don’t blast the rock to bits. Instead, Burkey’s model uses a bomb tunes to produce a crazy amount of x-ray radiation which heats up one side of the asteroid. You heat it up so much that the rock liquifies, then bubbles, and outgasses - and forms a propulsive engine, right on the surface, shooting out gaseous ultra-hot rock. Newton’s third law kicks in: as the asteroid ejects mass in one direction, the asteroid reacts by going the opposite way. So you have altered the orbital trajectory of the asteroid, averting disaster. The whole approach is very sensitive to the detonation height, asteroid composition and color, rotational characteristics, etc. So Burkey’s group has really made a simulation framework for modeling the right thing to do for a given asteroid.
- noman-land 3y agoHow do you prevent the asteroid from flying erratically like a balloon with the air rushing out?
- wcoenen 3y agoA balloon does that because it has very low mass and moment of inertia, compared to the thrust provided by the escaping air. An asteroid is not like that, even when heating one side with a nuclear bomb. The goal is to create a tiny change in its velocity vector, which still adds up to a significant trajectory change over time.
- jonplackett 3y agoIf on the other hand it IS balloon-like and hollow then let’s just let it crash into earth and pop.
- peteradio 3y agoIndeed, perhaps there will be some way to detect latex based asteroids in the future and avoid any unnecessary nuclear deployment.
- kleene_op 3y agoNot only is it essential for the defense of our planet, but it will be very important economically. Being able to capture asteroids within the moon's orbit to be able to mine them will propel humanity forward. After energy, material will be the most pressing issue.
- jojobas 3y agoI'd say it's a far cry. Nudging an asteroid at 10m/s a couple of months out might be enough to miss the Earth, to capture it in a lunar orbit you need two orders of magnitude more at the very least.
- pavel_lishin 3y agoCouldn't you play some games with orbital mechanics, and use the Earth-Moon system to capture the asteroid as it goes by? You don't have to expend all the delta-v to move it into an Earth or Moon orbit - you just have to put enough there to aim it at one spot, and let gravity do the rest.
- jojobas 3y agoThat's not how it works. You may save some energy by gravity assists, but you're not getting a factor of even 10.
- lolc 3y agoWe want the damn things to pass by. If we try to capture them we have to maneuver their trajectory very very close! I have no idea of astrophysics but due to their high speed the distance where they'd be in orbit would likely be below the surface of the earth! The orbital speed at the earth's surface is only 7.9 km/s[1] which is rather slow for an asteroid this close to the sun. Even if we found a favorable candidate it'd still be the difference between shooting at a mortar shell to change the direction away from you to avoid the shell hitting you, and shooting at the shell to get the shell to pass close to you. The later action has a much worse risk profile. [1] https://en.wikipedia.org/wiki/Orbital_speed https://en.wikipedia.org/wiki/Orbital_speed
- deleted 3y ago[deleted]
- yyyfb 3y agoCould we use this against the moon to move our orbit around the sun just a tad outwards, to counteract global warming effects
- yyyfbisagenius1 3y agoExcellent idea! We all know that, long term, earth's biosphere is doomed (for human habitation) and the goal is to start over with a terraformed Blue Mars. Of course. So projects like nuking our moon are a wonderful way to start practicing those bigger-picture geo-engineering projects without ... you know ... practicing on this little oxygen-rich wet rock we're all presently tethered to.
- yyyfbisagenius1 3y agoAlthough, now that I think about it some more, you'd probably want to be very certain of all the math before you turn a nontrivial amount of the Moon's surface into liquid molten rock belching out superheated gas. It would be a bummer if you, for example, were to accelerate the Moon into falling into the Earth (again).
- sebzim4500 3y agoThere is basically nothing we could do to Earth that would make it less habitable than Mars is. If we had the capability of terraforming Mars, it would be trivial to fix climate change here on Earth.
- swader999 3y agoHave you read the conjecture/conspiracy theory that Mars was nuked to oblivion in the distant past? This is good entertainment: https://youtu.be/q9Nuy7mFIsE?feature=shared https://youtu.be/q9Nuy7mFIsE?feature=shared
- ForRealsies 3y ago[dead]
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- dkbrk 3y agoThere's nothing wrong with refining models, but it's a bit besides the point. At a 1995 Planetary Defense workshop Edward Teller proposed the development of a 1Gt device for that purpose. Fusion bombs are actually quite straightforward to scale by adding more stages, so it wouldn't be terribly more difficult to produce a 10Gt device instead. What the model tells you is how large a device you need, but all that's needed is a conservative model that tells you the minimum size you need, and then you can add a generous margin of safety on top of that. The goal is to stop the asteroid hitting Earth, there's nothing wrong with deflecting it "too much". But right now we have exactly zero such devices prepared. Existing nuclear devices are about 3 orders of magnitude too small, and none of them are set up for a launch into an intercept. That's where the focus should be -- getting something, anything, of roughly the right order of magnitude that would provide a credible response to a detected inbound asteroid.
- andyjohnson0 3y ago> But right now we have exactly zero such devices prepared. Who would build/host/control such a weapon?
- coldtea 3y agoNot sure, but it would be deployed by a ragtag team of oil rig miners...
- jltsiren 3y agoWhoever is capable of solving the real challenge of delivering the warhead. Extrapolating from the existing high-yield bombs, the mass of a 1-gigaton warhead could be something like 200 tons. The Starship would probably be large enough to launch it into orbit, if you integrate the warhead in the upper stage and discard the lower stage. Then you would need 10+ refueling flights before you can launch it towards the asteroid. A 10-gigaton bomb would need a rocket 10x bigger than the Starship. Or you would have to build it in the orbit.
- avar 3y agoIvy Mike was around 70 tons and yielded 10 Mt, the B41 was around 5 tons yielding 25 Mt. Extrapolating from that a 10 Gt device should weigh around negative 25 thousand tons. You wouldn't need the starship to launch it, just attach it to the HMS Invincible and it would spontaneously float upwards into space.
- lupusreal 3y agoHow do you negotiate who gets to use their bomb for this? Whoever does it basically gets a free nuclear test that the other nuclear powers would probably be jealous of, but those same nuclear powers might also worry that their own bomb test, if they were permitted one test as compensation, might not go off without a hitch. They might therefore wish for there to be no nuclear detonations at all, to avoid the risk of being embarrassed. Furthermore there's also the issue of launch vehicle; some nuclear powers are more experienced with deep space missions than others, but fitting one country's bomb to another rocket may not be politically possible. America, maybe China, Russia or India could do it. The UK or France putting a nuke on an ESA rocket seems questionable. Pakistan and the other nuclear powers probably lack the requisite launch vehicle entirely but might publicly assert that the whole thing is a sham to violate the test / space weaponization bans.
- soundarana 3y ago> Whoever does it basically gets a free nuclear test that the other nuclear powers would probably be jealous If Russia/China/US/France/... want to do a test, they do it. There is nothing to negotiate and no one to beg for permission. France did nuclear tests in 1996 despite massive international outrage and pressure.
- dotnet00 3y agoRussia already pulled out of the nuclear test ban treaty, they have no leverage over the West getting "a free nuclear test" anymore, and anyway, all that the country doing the launch needs to do is show the trajectory estimation data. The only countries truly capable of something like this within the next couple of decades would be the US or China anyway. So only their opinion really matters and both of them would likely just complain for appearances but not actually seriously oppose the action. Anyone else doing the complaining is just looking for any excuse to pull out of the test ban treaty and should just be threatened with heavy sanctions if they do (as they would, even without a dangerous asteroid bearing down on Earth).
- cpursley 3y agoI’m worried about a Dark Forest strike than an asteroid. But glad to see progress.
- sgt101 3y agoIf these are your worries you live a blessed life! Remember that your (and my) ancestors lived in fear of too much rain, not enough rain, raiders, pestilence and the local overlord getting upset about something.
- alex_suzuki 3y agoI feel it‘s mandatory to mention „The Three-Body Problem“ by Cixin Liu here. What an amazing read.
- cpursley 3y ago3rd book in the series, incredible piece of writing.
- jackcviers3 3y agoThe problem with the dark forest hypothesis is that there's already no way to hide from the techinically advanced malignant actors that could execute a Dark Forest strike in the first place. If your civilization is technically advanced enough to be a potential threat to such an actor, the highly energetic actions you are undertaking for interstellar travel will be visible to all of space via radio and infrared telescopes. Given that it will be economically infeasible to launch all of the payloads required to produce interstellar spaceships from within the gravity well of a planet, the orbital infrastructure required itself will lkely be visible as a periodic dimming of the planet's sun. It too, will give off infrared radiation detectable by a far-off technically advanced malignant actor. There is no hiding in space. Your only hope for species and evolutionary survival in a dark forest is to aggressively disperse to uninhabited target systems. However, this also increases the likelihood that one of those systems will go rogue and eliminate the other ones it knows about. Given this, the best strategy seems to be first avoidance of contact, then diplomacy, then detente, and finally alliance and assimilation in a Dark Forest universe. The allied powers can ensure that any bad actors that attempt elimination strikes are outnumbered and eliminated themselves. On top of that, space is infinitely large. There are an enormous amount of finite resources within a planetary solar system which are way more energetically economic to exploit than ones in other systems. Once a civilization is forced to expand for survival beyond its local system, it is likewise economically cheaper to avoid warfare to claim one particular planetary system for its resources than to fight an interstellar war that risks the annihilation of the conflict participants' civilizations. There are literally an infinite number of systems to choose from. There's no reason to destroy other competitors when the resources you are competing for are infinite. In such a scenario, which our universe seems to be an example, the only reason for conflict is malignant choice. The prisoner's dilemma between two or more civilizations presented in the series would never need to occur. The philosophy behind Three Body is just terribly cynical and illogical in the face of what we know of the existing universe. It makes for a great story, but the type of aggression posited in technical species doesn't provide an evolutionary advantage. It should be noted that the entire Dark Forest philosophy presented in the book came from an unstable, traumatized, suicidal, xenophobic, nihilistic genius. Not the sort of person who you want forming the zeitgeist for existing in a much larger ecosystem of other civilizations. If you accept the premise, then the series is great. But the premise assumptions are fundamentally flawed.
- getwiththeprog 3y agoPublished in The Planetary Science Journal https://iopscience.iop.org/journal/2632-3338 https://iopscience.iop.org/journal/2632-3338 It is nice to see new fields of science, it shows the scale of where science could go.
- rib3ye 3y agoI was lucky enough to tour LLNL this year and saw a short presentation from this group and of course I asked them about the likelihood of an extinction-event asteroid hitting Earth. Their answer shocked me: They are already tracking an asteroid big enough to destroy an areas the size of Texas, that WILL hit Earth in about 140 years. Equally as shocking: we will need to launch our planetary defense solution with 30-40 years lead time to deflect the asteroid in time.
- tetris11 3y ago(lazy comment, but:) I'm sure we'll nip this one in the bud like we have with all other planetary crises we've encountered. Also: likely they were talking about Bennu[0], which is about 500m in diameter and is frequently quoted as devastating an area the size of Texas. 1: https://en.wikipedia.org/wiki/101955_Bennu https://en.wikipedia.org/wiki/101955_Bennu
- sigmoid10 3y ago>an asteroid big enough to destroy an areas the size of Texas, that WILL hit Earth in about 140 years There is no such thing. 101955 BENNU currently tops the special risk-list of potentially dangerous asteroids, with the latest estimate giving an impact probability of 0.037% in the year 2182. The only other candidate on that list has a probability that is even lower and and a timeframe of many centuries. https://neo.ssa.esa.int/risk-list https://neo.ssa.esa.int/risk-list
- ourmandave 3y agoFrom their About Page... Mission Focus Areas Crafting broad-ranging solutions with immediate impact. Might want to have the PR dept take a look at that wording.
- picadores 3y agoHow high are the chances of the asteroid disintegrating? As in frozzen snowball with peebles?
- JoeDaDude 3y agoI once met some people involved in Planetary Defense. One of them launched a crowdfunding campaign to fund development of his concept, the Hypervelocity Asteroid Intercept Vehicle. The crowdfunding campaign only raised some 4% of the needed funs. Nobody wanted to pay to save the Earth! https://www.indiegogo.com/projects/help-defend-earth-against-asteroid-threats#/ https://www.indiegogo.com/projects/help-defend-earth-against...
- XzAeRosho 3y agoTBH it's difficult to take serious any campaign running through these crowdfunding platforms. My "scam alert" sirens start to go off any time I see these kind of links.
- JoeDaDude 3y agoI don't know this for a fact, but I suspect the Principal Investigator was sold a bunch of baloney from the crowdsource outfit. They do take a large portion of the funding, after all. The PI had already been through Phase I and Phase II of NASA funding and likely went to crowdfunding because he lost Phase III. https://www.nasa.gov/general/an-innovative-solution-to-nasas-neo-impact-threat-mitigation-grand-challenge-and-flight-validation-mission-architecture-development/ https://www.nasa.gov/general/an-innovative-solution-to-nasas...
- IlliOnato 3y agoJust to illustrate the level of the nudges involved. The most dangerous currently known asteroid is Bennu, with 24 September 2182 as the most likely date of hitting Earth. To do so, Bennu must pass through a gravitational "keyhole" on 25 September 2135. That keyhole is about 5 km wide. (To compare, the asteroid itself is about 0.5 km wide). It's like deflecting a projectile that shoots at a 5 km target from the distance of a couple hundred million km.
- swader999 3y agoA test is worth a thousand words. Let's repurpose the arsenals.
- dingaling 3y agoMost of the arsenal nowadays is fairly low-yield compared to the heyday of the 1960s. The largest deployed US weapon was the B41 with a yield of at least 25MT. The closest contemporary is the B83 at 1.2MT.
- cookingmyserver 3y agoGlad to see this researched more. It has become popular in pop culture science to bring up the "myth" of using nukes to stop/deflect asteroids. Apparently, their incorrect use in a few movies discounts them ever being used. Even "science communicators" have participated in evangelizing the ineffectiveness of nukes, never realizing you don't have to land on the asteroid and drill a nuke into its core to use it effectively. There have already been papers on deflection via the ablation of an asteroid via nuclear detonation, so the idea is not new. However, it looks like with the knowledge gained with the DART mission this research will enable better modeling.
- jdewerd 3y agoWhat's more, the technique is in one sense very well explored: ablation drive is how fusion bombs work. Putting Deuterium and Tritium (well, LiD which becomes D+T) in the middle of a fission bomb doesn't squeeze it hard/long enough to boost the yield of the fission bomb 1000x. Focusing the x-rays from a fission bomb onto a uranium "pusher" and driving it forward with the reaction force of vaporizing uranium does squeeze hard enough to generate fusion yield far in excess of the fission primary. If this sounds vaguely familiar, you might be thinking of the Hohlraum at the NIF that recently made the press for getting more energy out than was deposited in. That strategy doesn't scale into a power plant but it does a brilliant job of simulating fusion bombs, which is why the DOE / NNSA can pursue it with so much money.
- mrangle 3y agoThe more surviveable option is probably to consider asteroid impacts to be an unstoppable larger part of the evolutionary cycle, however terrifying. Rather than risk destroying ourselves via mishandling low-probability countermeasures. Spraying sun blocking aerosol into the atmosphere to lower temps probably falls into the same category.
- michaelmrose 3y agoGiven we already have nuclear weapons the probable risk of developing such measures is logically meaningless. It's not like we are giving nasa armed ICBMs ready to fire at a moments notice. We are merely exploring a new use for existing hardware which could be deployed in a reasonable time frame. We also aren't liable to experiment on any mountain sized rocks and accidentally steer it into our path. We can absolutely experiment with manageable sized rocks. The only meaningful risk other than wasting our money is dealing with something that is within the margin of error and turning a near miss into a hit. As this risk is inherently a small subset of the probable hits its hard to imagine how this risk could possibly be larger than its superset. The remaining risk would be in an accident during a test run involving a live nuke. It's not obvious that such a test would be advantageous to conduct on balance nor needed.
- reset2023 3y agoFinally, someone working on something for the common good.
- egberts1 3y agoMmmm, majority of vector thrush is heat-based atmospheric pressure wave. How much of that vector got reduced when operating in near vacuum? So it becomes more a game on how fragmented the asteroid can become upon a nuclear detonation ... in near-vacuum condition.
- hermitcrab 3y agoLooking forward to melodysheep's 'The Asteroid Strikes Back'. Trailer here: https://www.youtube.com/watch?v=YzQYdx30HYE https://www.youtube.com/watch?v=YzQYdx30HYE
- MichaelMoser123 3y agoif anyone tries to check this approach in practice (on a smaller scale), wouldn't that be prohibited under the Partial Nuclear Test Ban Treaty ? https://en.wikipedia.org/wiki/Partial_Nuclear_Test_Ban_Treaty https://en.wikipedia.org/wiki/Partial_Nuclear_Test_Ban_Treat...
- dtgriscom 3y agoSay you have a small incoming asteroid that, without intervention, will hit country A. As you add momentum to the astroid, the Earth impact point will move in a (mostly?) continuous fashion. Everyone wants it to miss the Earth completely, but what if the intervention is botched and it instead hits a different country B? And will countries that wouldn't be touched by the initial expected impact object to any intervention that raises their own risk?
- lr1970 3y ago221 comments and nobody mentioned a great satirical movie "Don't look up". Amazing :-)