Russian boffins want to nuke asteroids

Re: Treaties schmeaties

It would be much easier and reliable to deliver and fire rocket boosters to change trajectory.

Re: Treaties schmeaties

Problem is you've then got radioactive meteor fragments covering the planet. That's why they made the point that they were doing this on asteroids which came close but didn't quite hit as they left, so that when they circle back they won't be a threat

Yah, but the real, actual and operative impediment to nuking an asteroid

Is that it justifies the stockpiling of ICBM's and their payloads during the Cold War. That Comintern directed pacifist Nuclear Disarmament carnival from the 50's and 60's is suddenly made to look like a lemming suicide mission. Can you imagine the jaw grinding when the headline, "Planet Earth Saved by Giga Ton H-bomb Originally Targeting Washington DC" hits the web waves? It would be a pan national St. Vitus Dance mosh pit and worth an investment in popcorn futures.

Re: Treaties schmeaties

"It's currently illegal to fire off nukes into space"

Since when did Russia start caring about international law?

Re: See you next time around!

Given the megatonnage of surface-based nukes we've detonated just to tweak each other nose in the past 70 years, somehow I do not think another 1, 10, or 100 megatonnes to save everybody's ass is going to matter much.

Re: See you next time around!

Surely some of the (now radioactive) detritus would stay on the same relative path

So?

If that detritus is now small enough to burn up in the upper atmosphere then it'll be a small radiation dose deposited globally, small in comparison to the results of atmospheric H-bomb testing (which we did in the past, and survived with few casualties). If it still reaches the ground the radioactivity will likely be far less of a disaster than the consequences of megatonnes (or gigatonnes) of kinetic energy, which in turn will be a fraction of the original disaster if we had not used the nuke.

Of course, if we started planning now to get a nuclear-powered ion-drive tug on standby in orbit, we would not have to resort to desperate measures at some unknown time in the future. It would not be a significant radioactive re-entry hazard until its core had been powered up for some time, at which point it would no longer be in earth orbit. If virgin enriched uranium fuel got vaporised in a launch accident and/or lost in the ocean, that would not be any sort of radiological disaster.

Re: Mihail, change the status to "Brown Trouser Time"

For future reference, brown trousers time in Russian is "Медвежья болезнь".

That translates as "Bear sickness". Apparently, when the sh*** hits the fan, a brown bear will empty its bowels (same as quite a few other animals and birds) to ensure it does not carry any extra weight when it needs to leg it.

Re: Mihail, change the status to "Brown Trouser Time"

> запуск!

It's "пуск!", but перегрузка is real.

Re: One small problem....

Hello, "future threat", yes? That is, we have already seen this asteroid aforehand, it's passed by this time, but its future path has been well-characterised enough that we can tell that N+1 or N+m orbits from now that it and the earth will definitely intersect.

So no use for the new guy on the block introducing themselves with a "mind if I barge in?", but useful for something we've gotten a whiff of and don't want plopping onto our couch.

But for all that, making sure that whatever much smaller pieces still will intersect with earth have been christened with eau-de-Pu doesn't thrill me.

As someone else here suggests, send a thruster up and shove the whole thing into a safe orbit. That is applicable for many more cases, such as asteroids that haven't yet passed by cuz they're gonna hit first time up at bat. Go for the more general case rather than the special case mooted here, okay?

Re: One small problem....

"If it's moving away from us.. it missed"

...This time

It'll be back.

Re: One small problem....

"Methinks someone just wants to get nukes in space."

What is clearly needed is more sharks with lasers. ...in spaaaace!

Movie nukes

Just make sure to pack the manual detonator cord. Because that's normal to design for a nuke.

Re: I thought nukes were not a solution ?

Venturing a guess - using a penetrator, instead of a proximity or surface burst. This is feasible for "leaving" rocks - for "incoming" rocks the delta-v for a penetrator to be feasible is off the scale.

If you use a penetrator, the adjacent rock is instantly vaporized providing the necessary impactor so that the energy is not wasted.

There are some tech issues with that though:

1. You need to get the speed just right. So you need a lot of more fuel to drop the delta-v down so that the nuke does not disintegrate on impact.

2. In an ideal world, you will also need a pilot probe(s) to impact the asteroid before the nuke so that you identify it correctly as rock, ice, whatever and get the delta-v down to the correct value for the penetrator reaching optimal depth

3. For a half a ton to a ton worth of nuke (assuming a 10Mt warhead) you now need several tons of armor to form the penetrator and ensure that the nuke arrives to the spec-ed depth intact. That, once again, means a boatload of fuel.

4. It definitely works only on "leaving" rocks as suggested by these guys. An incoming rock has delta-v in the 10s of km/s. We do not possess the technology to reach it in time, drop the speed to a point where the penetrator will not disintegrate and perform an attack run.

Re: I thought nukes were not a solution ?

Even the slop trap Armageddon made the misfits drill into the asteroid in order to explain why the nuke would work. ... I am therefor sceptical when reading that shooting off a few nukes to have them blow up on a large asteroid's surface would "turn most of the asteroid into liquid and gas".

Armageddon was dealing with an asteroid the size of Texas (i.e., bigger than Ceres) with 18 days before impact. Such large bodies would be gravitationally consolidated and would have survived numerous megaton-level impacts in the past. Substantial handwavium boosted with large quantities of unobtainium were required to destroy the asteroid in time for the so-called love story side plot to reach its Hollywood ending.

Meanwhile, the proposed target asteroids (200-300m) by this paper are about the volume of the crater excavated by Operation Plowshare's 104-kiloton Sedan shot but the proposed demolition charges are 1 megaton. You have an excess of energy to overcome disadvantages like inefficient energy transfer.

However, I'd note that nuclear disassembly of asteroids does not require high speed interception and proximity detonation. You're probably making the interception years ahead of time so the weapon can make a soft touch down (presumably carried by a derivative of some other asteroid probe, like Rosetta). A weapon detonated on the surface of an asteroid will pump about half its energy into the asteroid's surface because the asteroid occludes about half the visible sky, more if you find a nice crater to settle in.

Asteroid material isn't air, but when heated to several bajillion degrees by half the energy release of the demolition charge it will act quite like a fireball and move some mud. See: Sedan shot. Bonus: you get a rocket-like effect from the surface because the obvious expansion path between the massive, disintegrating bulk of the asteroid and empty space is into space. You destroy and deflect.

You missed the part where it is stated that the nuking would happen after the body passes Earth - therefor sending the pieces every which way toward Mars and Mercury.

So Earth escapes intact - but this plan does not bode well for future Martian colonists.

Re: Just one thing

As previously noted upthread, we've set of plenty of nukes inside our atmosphere, a few bits of rock that have had at least a year (assuming it's in a similar orbit to the Earth) to 'cool off' won't be too much of a bother.

Re: Nukes in SPAAAAACE

Yeah, but what else are you going to do on a Tuesday morning? Work?

By using a Mac to upload a virus into their mothership, obviously.

Re: I must be missing something

I believe the idea is that any risks from the radioactive debris shower will affect several generations down the line rather than us, when it next comes round. Someone else's problem, in other words.