If an asteroid is on a collision course with Earth

[KingOrfeo]

and you blow it up with nuclear weapons, we now have a cloud of fragments of the same aggregate mass on a collision course with Earth, going at the same velocity and packing the same aggregate kinetic energy, only now they're radioactive.

Who ever thought this was a good solution?

 

[nerfhearder]

and you blow it up with nuclear weapons, we now have a cloud of fragments of the same aggregate mass on a collision course with Earth, going at the same velocity and packing the same aggregate kinetic energy, only now they're radioactive.

Who ever thought this was a good solution?

I'm not sure too many people think it's a good idea just because in most cases it wouldn't work anyway.
As for the fragments, if the rock is heading straight at us and is blown up the fragments won't continue in the same direction, they'd go all over space. Some may still hit us but with much less damage.

 

[BoyNextDoor]

Dude. You hire Bruce Willis to drill - baby - drill!

 

[BrokeDick]

and you blow it up with nuclear weapons, we now have a cloud of fragments of the same aggregate mass on a collision course with Earth, going at the same velocity and packing the same aggregate kinetic energy, only now they're radioactive.

Who ever thought this was a good solution?

https://up1.xhcdn.com/000/132/781/186_1000.gif

"Karl, are you listening to me?"

 

[Hard_Rom]

But the smaller pieces are much more likely to burn up in the atmosphere. Better than a dinosaur killer smacking us. Radioactive! We just dodged a dinosaur killer. We can live with a bit more radioactivity.

 

[M. Jordan]

If it happened to be heading for Washington DC, I'd ignore it.

 

[nerfhearder]

But the smaller pieces are much more likely to burn up in the atmosphere. Better than a dinosaur killer smacking us. Radioactive! We just dodged a dinosaur killer. We can live with a bit more radioactivity.

As it stands right now if a rock that big were coming at us we would only be able to kiss our asses goodbye anyway. Be better off nuking ourselves to get it over with.

On the subject, if you've never seen it watch "These Final Hours." Brutal.

 

[nerfhearder]

If it happened to be heading for Washington DC, I'd ignore it.

Or pretty much anywhere in California, Texas, Indiana, New York and Florida.

 

[phrodeau]

Best is to divert the orbit, otherwise shatter it to pieces too small to survive atmospheric entry. Earth's magnetic field will keep off most of the radiation, like in the Van Allen belts.

 

[Hard_Rom]

I worry about getting killed by a asteroid as I do a terrorist attack or amusement park ride mishap. Also prefer not to waste money on lottery tickets.

 

[BrokeDick]

But the smaller pieces are much more likely to burn up in the atmosphere. Better than a dinosaur killer smacking us. Radioactive! We just dodged a dinosaur killer. We can live with a bit more radioactivity.

https://up1.xhcdn.com/000/132/781/187_1000.gif

"Karl, smaller pieces are much more likely to burn up in the atmosphere."

I've heard that before. This Slurpee sure tastes good.

 

[Hard_Rom]

Boring! Likely to be on iggy list due to terminally boring post content.

https://up1.xhcdn.com/000/132/781/187_1000.gif

"Karl, smaller pieces are much more likely to burn up in the atmosphere."

I've heard that before. This Slurpee sure tastes good.

 

[Mello_SixtyNine]

and you blow it up with nuclear weapons, we now have a cloud of fragments of the same aggregate mass on a collision course with Earth, going at the same velocity and packing the same aggregate kinetic energy, only now they're radioactive.

Who ever thought this was a good solution?

If we had a few years heads up, it might be a good idea to launch a few dozen nukes at it, but not simultaneously...launch them individually in 8 hour increments. Also, instead of trying for a direct hit, have the nukes detonate as they are passing the asteroid. This way, the shockwave from the blasts could nudge it slightly. Repeat a few dozen times and hopefully if there is enough distance between the asteroid and the Earth, those little pushes would cumulatively be enough of a course correction to miss the Earth.

Just saying...

 

[KingOrfeo]

As for the fragments, if the rock is heading straight at us and is blown up the fragments won't continue in the same direction, they'd go all over space.

No, conservation of momentum -- some would be diverted in this or that direction by the blast, but the fragment-cloud's general course would remain Earthward.

 

[nerfhearder]

If we had a few years heads up, it might be a good idea to launch a few dozen nukes at it, but not simultaneously...launch them individually in 8 hour increments. Also, instead of trying for a direct hit, have the nukes detonate as they are passing the asteroid. This way, the shockwave from the blasts could nudge it slightly. Repeat a few dozen times and hopefully if there is enough distance between the asteroid and the Earth, those little pushes would cumulatively be enough of a course correction to miss the Earth.

Just saying...

That's the only way a nuke would work against a rock big enough to wipe us all out. Trying to actually blow it up wouldn't work from the outside. Same argument they used in that idiotic movie. Probably the only thing they got right.

 

[KingOrfeo]

Best is to divert the orbit, otherwise shatter it to pieces too small to survive atmospheric entry. Earth's magnetic field will keep off most of the radiation, like in the Van Allen belts.

A radioactive rock could still get through the atmosphere. And if it burns up, now we've got a cloud of radioactive gas in the atmosphere.

 

[nerfhearder]

No, conservation of momentum -- some would be diverted in this or that direction by the blast, but the fragment-cloud's general course would remain Earthward.

I'm not gonna pretend to be a rocket scientist but I think outside forces negates that. I think.

 

[Hard_Rom]

A radioactive rock could still get through the atmosphere. And if it burns up, now we've got a cloud of radioactive gas in the atmosphere.

You can date some human remains by the strontium 90 in the bones after nuclear tests in the atmosphere. Nothing new.

 

[Colonel Hogan]

If we had a few years heads up, it might be a good idea to launch a few dozen nukes at it, but not simultaneously...launch them individually in 8 hour increments. Also, instead of trying for a direct hit, have the nukes detonate as they are passing the asteroid. This way, the shockwave from the blasts could nudge it slightly. Repeat a few dozen times and hopefully if there is enough distance between the asteroid and the Earth, those little pushes would cumulatively be enough of a course correction to miss the Earth.

Just saying...

*sigh*

From NASA:

When a nuclear weapon is detonated close to the Earth's surface the density of the air is sufficient to attenuate nuclear radiation (neutrons and gamma rays) to such a degree that the effects of these radiations are generally less important than the effects of blast and thermal radiation. The relative magnitudes of blast, thermal and nuclear radiation effects are shown in figure 1 for a nominal fission weapon (20 kilotons) at sea level.

The solid portions of the three curves correspond to significant levels of blast, thermal, and nuclear radiation intensities. Blast overpressures of the order of 4 to 10 pounds per square inch will destroy most structures. Thermal intensities of the order of 4 to 10 calories per square centimeter will produce severe burns to exposed persons. Nuclear radiation dosages in the range 500 to 5,000 roentgens are required to produce death or quick incapacitation in humans.

If a nuclear weapon is exploded in a vacuum-i. e., in space-the complexion of weapon effects changes drastically:

First, in the absence of an atmosphere, blast disappears completely.

Second, thermal radiation, as usually defined, also disappears. There is no longer any air for the blast wave to heat and much higher frequency radiation is emitted from the weapon itself.

Third, in the absence of the atmosphere, nuclear radiation will suffer no physical attenuation and the only degradation in intensity will arise from reduction with distance. As a result the range of significant dosages will be many times greater than is the case at sea level.

https://www.hq.nasa.gov/pao/History/conghand/nuclear.htm

This is why nuking an asteroid will not work and would produce a radioactive massive object continuing on its collision course toward Earth. Quite simply, there would BE NO FRAGMENTS.

"Well, Colonel, how do you explain the violent explosion in space aboard Apollo 13 which the astronauts clearly felt and reported to Mission Control"?

The explosion on Apollo 13 was an explosion OF an onboard oxygen tank. The shockwave was produced BY the sudden ignition of the oxygen itself. Once consumed, which was very quickly, there was no shockwave. Debris, of course, accelerated out and maintained speed for quite some time. In fact, much of it may still be moving, albeit slowly. But you could have been in a companion space vehicle traveling, say, 50 feet from Apollo 13 and, were it not for the debris, you would not have felt a thing.

The "best" plan to divert a killer asteroid seems to be a soft landing of several powerful vehicles on the surface at strategic distances apart, point the engine nozzles back out into space and fire the engines so as to change the asteroids trajectory and miss Earth.

But any single piece of space debris big enough to destroy Earth is not going to be "blown up" with any nuclear weapons we possess.

 

[Mello_SixtyNine]

*sigh*

From NASA:
First, in the absence of an atmosphere, blast disappears completely.

So...zero shockwave if you blow up a nuke in space.
Learn something new every day.

 

[Rightguide]

and you blow it up with nuclear weapons, we now have a cloud of fragments of the same aggregate mass on a collision course with Earth, going at the same velocity and packing the same aggregate kinetic energy, only now they're radioactive.

Who ever thought this was a good solution?

NASA has funded research under the NASA Innovative Advanced Concepts (NIAC) program.

 

[nerfhearder]

*sigh*

From NASA:



This is why nuking an asteroid will not work and would produce a radioactive massive object continuing on its collision course toward Earth. Quite simply, there would BE NO FRAGMENTS.

"Well, Colonel, how do you explain the violent explosion in space aboard Apollo 13 which the astronauts clearly felt and reported to Mission Control"?

The explosion on Apollo 13 was an explosion OF an onboard oxygen tank. The shockwave was produced BY the sudden ignition of the oxygen itself. Once consumed, which was very quickly, there was no shockwave. Debris, of course, accelerated out and maintained speed for quite some time. In fact, much of it may still be moving, albeit slowly. But you could have been in a companion space vehicle traveling, say, 50 feet from Apollo 13 and, were it not for the debris, you would not have felt a thing.

The "best" plan to divert a killer asteroid seems to be a soft landing of several powerful vehicles on the surface at strategic distances apart, point the engine nozzles back out into space and fire the engines so as to change the asteroids trajectory and miss Earth.

But any single piece of space debris big enough to destroy Earth is not going to be "blown up" with any nuclear weapons we possess.

I knew I was missing something about that whole thing (I had read about NASA's ideas a while back) but figured it was just me being old and thought the idea sounded rather good. Live and learn. Or re-learn I guess.

 

[KingOrfeo]

I'm not gonna pretend to be a rocket scientist but I think outside forces negates that. I think.

No, it does not negate the object's original momentum, it merely adds a new force vector to its trajectory.

 

[nerfhearder]

No, it does not negate the object's original momentum, it merely adds a new force vector to its trajectory.

I have no idea if that's true or not but assuming it is, so what? Still better than letting the whole thing hit us. That's assuming you find a way to blow it up in the first place which seems like some slim odds.

 

[KingOrfeo]

This is why nuking an asteroid will not work and would produce a radioactive massive object continuing on its collision course toward Earth. Quite simply, there would BE NO FRAGMENTS.

Not from a blast, which depends on air, but . . . what if, for some incomprehensibly stupid reason, you hired an oil-rig crew to drill a deep hole in the asteroid and drop the nuke into it?