No I was really thinking it would be more about accelerating the speed at which you could make decisions. Interplanetary probes and their research programmes run at a very slow measured pace. Here we want to be able to work out exactly where a nuke must be placed and do it very quickly - having already launched the nukes right behind the guidance and imaging probe. Given we have no good idea of the shape, rotation or composition of the asteroid, faffing about once the nukes arrive working out what to do is going to lose a lot of time.
Yeah, although you would need to trust the other nations that the nuke they launched, and just so happened didn’t use, and is still up there, didn’t just happen to also have a re-entry vehicle. OTOH, you don’t absolutely need a re-entry vehicle. That is just the most efficient way of breaking - using the atmosphere. If you have a nice amount of fuel remaining in your system you can decelerate with that, and the nuke can just fall through the atmosphere with only trivial heating. Virgin Galactic doesn’t need a heat shield.
You can’t. Sadly you just take the hit that half the energy has basically vanished into space.
Inside the nuke things are as weird as one can imagine, and there are asymmetries in boosted and thermonuclear weapons. You have the notion of neutron reflectors and various other ways of modifying the physics to guide the process. However these things last nanoseconds before they turn into superheated plasma, and I very much doubt there is any sort of asymmetry in the energy of the fireball once it gets much more than a metre in diameter. Maybe selective asymmetry in the tampers will yield some difference in the nature of radiation in different directions. As I noted earlier you probably want to favour gamma radiation over neutrons to carry the energy to avoid useless deep heating of the rock and favour maximum energy going into vaporising the surface rock. OTOH, I don’t know enough (like nothing really) about the relative energy deposition that would occur and is needed. Just seems like it would be a reasonable thing to do. We have a vast body of knowledge about the effects of nukes and such things as cratering and energy balances - many many tests before the bans came in.
Any chance we could win the game, at least with enough advance notice, using a billiard shot? Instead of trying to deflect the 5km asteroid, just find a much smaller asteroid already on a near-collision course with the big asteroid, and deflect the small asteroid enough to nudge it into a deflecting collision with the larger threat.
If you can get it to collide at all, the momentum transfer will be huge. Obviously time until Earth collision will be a major factor in determining what impulse is needed, but the impulse would be much greater than thrusting on the big asteroid itself. Remember that you’d be exploiting the smaller asteroid’s existing momentum — the human-provided impulse would be to redirect the small asteroid, not to increase its energy.
If it’s a nuclear explosion nearby, then as mentioned, the main impact is high-energy particles, photons and neutrons, some vaporised bomb components. Causing a collision using another high-energy rock is simpler, but then how do we give that rock the necessary momentum and direction. It seems to me the most effective diversionary tactic is to bury the nuke inside the asteroid deep enough (shallow enough) so it blows a substantial chunk of the asteroid off. preferably this would be from the side - or some fancy orbital math to determine which direction course change diverts the asteroid from collision course the most. It could be that speeding it up or slowing it down would work better. The only worry is where that chunk blown off ends up, but a few of those apartment-block sized meteors is preferable to a KT event. The only problem is - how many of these bombs do you have to set off to effectively change the course of the asteroid? A sphere say, 20m on a side, about the size of the recent Russian meteor vs. a 10km sphere, a ratio of 20^3 vs 10,000^3 - that chunk would have to fly off at one helluva velocity to divert the asteroid very much. Or, we need that huge fleet of heavy launch vehicles at the ready.
Lutetia is unusual in that it probably formed in the inner solar system, perhaps from the Lunar formation event. So it is more solid, and drier, than most.
We probably don’t have to worry about the big objects, anyway; it is smaller objects, around 100 metres or less, that could cause a credible threat. These often tumble so fast and erratically that they have negative gravity on their surface at times, so they are likely to be single objects not rubble piles. Nukes would probably work for these solid objects, though I’d prefer to use gravity tugs if they could be made to work.
Tripler, not a slight or an insult, but do you have a college degree? When Stranger wrote his little post, the main topic was about an effect that doesn’t physically matter.
This was apparent in the original post.
Every poster in this thread who actually passed physics 1 has confirmed this. The only ones arguing against me…like you…just try to twist the words around or make personal attacks.
