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GladWrapMan
2006-Feb-20, 02:34 AM
What would happen to an explosive if it exploded in space?

Fr. Wayne
2006-Feb-20, 02:50 AM
Without a medium (e.i. atmosphere or ion cloud) no sound would it make.

Van Rijn
2006-Feb-20, 03:04 AM
What kind of explosive? What is your distance from the explosion?

In the case of a nuclear bomb, for instance, there would be relatively little blast effect but substantial surface heating, depending on distance.

cjl
2006-Feb-20, 03:27 AM
Almost any explosive would detonate just fine, however it would simply disperse all the material in the form of gas at high velocity. You'd get a lot of hot air going in all directions (kind of like at a convention of lawyers ;) ) and a bright flash, but that's about it.

alainprice
2006-Feb-20, 04:08 AM
It would explode.

All jokes aside, it makes a growing sphere....quite nice to look at in the case of nuclear.

the_bullet
2006-Feb-20, 08:07 AM
Most if not all explosives have their own oxidant, so would explode fine.

cjl
2006-Feb-20, 08:38 AM
I cant think of one that does not have its own oxidizer, unless you talk about a fuel air bomb. Many common explosives however, are ANHE's, and have all the oxygen they need, and as such, would work just fine.

As a matter of fact, so would black powder, as would smokeless powder and solid rocket fuel.

The Saint
2006-Feb-21, 10:00 PM
Without an atmosphere, would the range in the first 30 seconds of the dangerous radiation and blast effects from an Hiroshima type A bomb, a Neutron bomb and a dirty cobalt H bomb exploding in space be any different than on Earth?

Van Rijn
2006-Feb-21, 11:23 PM
There would be minimal blast and without matter to block it, more immediate radiation. There would be a heavy x-ray flux, and intense surface heating of any objects that happened to be near. The blast comes from intense heating of surrounding matter. Little matter=little blast.

There wouldn't be much point in a cobalt bomb in space (the idea there is to spread radioactive fallout in an atmosphere). A neutron/ER bomb might be useful for killing ship's crew, however.

antoniseb
2006-Feb-21, 11:24 PM
Without an atmosphere, would the range in the first 30 seconds of the dangerous radiation and blast effects from an Hiroshima type A bomb, a Neutron bomb and a dirty cobalt H bomb exploding in space be any different than on Earth?

Yes, the atmosphere contains the explosion and absorbs radiation. It also provides some stuff buffet objects nearby, which get less radiation, but a worse blast than objects at a similar distance in space.

Why, what are you planning?

Kesh
2006-Feb-22, 01:24 AM
Here's a case for folks to sink their teeth into...

On another board, folks were discussing how the Battlestar Galactica was able to survive direct hits from multiple nukes. It was pointed out that the majority of a nuke's destructive ability came from the pressure wave of air being displaced... which doesn't exist in space.

So, let's take a low-yield nuke as an example. What happens when it goes off in space?

Van Rijn
2006-Feb-22, 06:16 AM
I found this page that specifically discusses explosions in space:

http://spider.ipac.caltech.edu/staff/waw/mad/mad12.html

It appears to be well done. It discusses both chemical and nuclear explosions.




On another board, folks were discussing how the Battlestar Galactica was able to survive direct hits from multiple nukes. It was pointed out that the majority of a nuke's destructive ability came from the pressure wave of air being displaced... which doesn't exist in space.

So, let's take a low-yield nuke as an example. What happens when it goes off in space?

As mentioned before, there would be intense surface heating. Keep in mind that the Orion Drive concept is based on the idea of dropping low yield nukes out the back end of a spacecraft. In that case, you would either surround the bomb with low density material (plastic perhaps) or allow the nuke to vaporize a layer off of the pusher plate. In either case, the energy from the bomb would be used to vaporize material that would be directed and used for thrust. The point is that, given a massively built ship, it should be possible to blow moderate sized nuclear bombs next to a ship and expect it to survive.

With a low yield nuke used offensively, there would be intense x-rays, some more penetrating than others and a bit of gamma. There would be some neutrons, possibly a lot if the bomb was optimized for it. For protection, you would probably want layered armor with the expectation that the surface would be vaporized, and designed to take compressional forces and substantially reduce radiation penetration.

All sensors and electronics would need to be hardened, not so much for EMP, but the intense flash and x-rays. You would want lots of redundancy.

The Battlestars have the advantage that they are truly massive and do, in fact, have a lot of armor. Something like that could take nukes at close range.

The Saint
2006-Feb-22, 10:16 PM
"Starfish Prime" detonated a 1.5 mT bomb at 250 miles up in 1962.

http://en.wikipedia.org/wiki/Starfish_Prime
http://www.nv.doe.gov/library/films/film.aspx?ID=50me

They must've been pretty sure of their rockets, guidance and failsafe to try such a shot!

joema
2006-Feb-23, 04:22 PM
A few items:

*There's no blast effect in space. Blast requires atmosphere.

* If you're close enough, there'd be heat, but heat is much less a factor than radiation. You'd be killed by radiation at much greater ranges than heat.

* All nuclear warheads aren't the same. They can be tailored to provide different energy in different spectrums.

* The ideal warhead type for space is a neutron or "enhanced radiation" warhead. It emits a far greater % of it's energy as radiation than heat. Everybody knows that so in any space weapon scenario it's virtually certain that all nukes would be enhanced radiation warheads.

* A neutron warhead is so effective, its lethal radius (from radiation) would be greater for a one-kiloton neutron bomb than for a 13- kiloton regular fission warhead.

* A neutron warhead emits so much radiation relative to heat, you could probably stand unprotected on earth at a range where you'd be unharmed by the heat/blast, yet killed by the neutron radiation.

* You cannot effectively shield against neutron radiation. The radiation is very penetrating.

*At least one rocket blew up or crashed during the high altitude nuclear tests in the 1960s. It caused no major problem. There are multiple safety devices. Unlike TV, a nuclear warhead won't detonate if you cut the wrong wire or jolt it.

ngc3314
2006-Feb-23, 04:52 PM
"Starfish Prime" detonated a 1.5 mT bomb at 250 miles up in 1962.

http://en.wikipedia.org/wiki/Starfish_Prime
http://www.nv.doe.gov/library/films/film.aspx?ID=50me

They must've been pretty sure of their rockets, guidance and failsafe to try such a shot!

Both the US and USSR did whole series of such high-altitude blasts, largely to understand the effects of the bombs on their systems (a side effect was the realization of how important EMP could be, when a test on a rocket launched from Johnston Island accidentally lacked out Honolulu about 400 miles away). I shuddered to learn that there were such space nuclear tests on both sides within 24 hours of each other during the Cuban missile crisis. Someone didn't get the memo.

Just as stunning - there was a launch failure of the Bluegill Prime space nuclear explosion, showering the fissile material over the island. (I keep imagining how the lowest-rank naval personnel would get sent out to clean it up...) And Starfish Prime was so named because the initial Starfish bomb ended up raining back over Johnston Island when its booster failed about a minute after launch.

Van Rijn
2006-Feb-24, 08:24 AM
A few items
*There's no blast effect in space. Blast requires atmosphere.


More generally, blast requires matter. For instance, a nuclear device surrounded by a shell of some material (such as a light plastic) will produce a blast or explosive effect.

So more correctly, there will be minimal blast effects in space, unless the bomb is specifically set up for it - for instance, by putting a nuke in a small asteroid/large rock.



* If you're close enough, there'd be heat, but heat is much less a factor than radiation. You'd be killed by radiation at much greater ranges than heat.


X-rays cause intense surface heating, especially near the device.



* You cannot effectively shield against neutron radiation. The radiation is very penetrating.


It would be difficult to shield against neutron radiation, though not physically impossible. It takes a lot of shielding (mass), of course. You certainly would prefer to keep your distance from the bomb.

joema
2006-Feb-24, 03:50 PM
...So more correctly, there will be minimal blast effects in space, unless the bomb is specifically set up for it - for instance, by putting a nuke in a small asteroid/large rock.
You could even argue there's always blast effect in space, since it's not a total vacuum. If there's even one atom per cubic meter, that will technically cause atmospheric blast. However these effects aren't meaningful relative to the other emission components, which is likely what the poster wanted to know.


X-rays cause intense surface heating, especially near the device.
Correct. However I meant thermal heat from the bomb, not induced heating from X-rays. With a neutron bomb, only about 20% of output is X-rays, so neutron radiation is the dominant component. At most distances you'd be long dead from neutron flux before either direct or induced heat became a problem.


It would be difficult to shield against neutron radiation, though not physically impossible. It takes a lot of shielding (mass), of course. ..
Considering a neutron bomb can immediately kill a crew shielded inside an armored battle tank, and that includes atmospheric attenuation, yes it's difficult to shield against.

http://www.projectrho.com/rocket/rocket3x.html

In the vacuum of space, a neutron bomb is 100 times more deadly at 1000 meters than within the atmosphere. A one megaton device is fatal to an unshielded human at 300 kilometers (!!) If the human was shielded inside a spacecraft constructed like a terrestrial battle tank, it would only reduce the lethal distance by about 22%, to 234 km.

http://www.wordiq.com/definition/Neutron_bomb

As you said, it's not impossible to shield against, just very difficult.

Back to the poster's question: "what would happen?" Unlike how space explosions are depicted in Science Fiction movies, at many engagement distances the ship wouldn't "rock and roll", the detonation as viewed from the ship wouldn't be blindingly bright, no smoke, no sound, no significant thermal heating. Just a brief blueish flash, then the crew would quickly die from neutron radiation.

Lance
2006-Feb-24, 04:56 PM
So more correctly, there will be minimal blast effects in space, unless the bomb is specifically set up for it - for instance, by putting a nuke in a small asteroid/large rock.
Bruce Willis has already demonstrated this.