Jump to content

What would happen if you nuked different planets.


Recommended Posts

I do not have a very good understanding of nukes other than that they split atoms and get a lot of energy to make a big boom. I also know that in a vacuum with no atmosphere there is no mushroom cloud so the fireball just keeps expanding and does a lot more destruction but I don't really know how it would work on other planets with atmospheres I guess on venus it would be smaller cause of the thicker atmosphere. i remember there was some drawing i saw of some future space bomber dropping a nuke on a hovering soviet base on jupiter and there is a massive mushroom cloud but would that actually be the case. so please tell me guys how it would be different

Link to comment
Share on other sites

Moar gas (thicker atmosphere) equals a more destructive blast wave generally speaking.

 

Less gas makes a blast wave that is less destructive.

 

A nuke in a vacuum is bascislly just a flash of bright light.... blink and you will miss it. Yes the radiation csn hurt if not shielded, and a direct hit would do serious heat damage besides kinetic, but overall less damage than anywhere with an atmosphere because no atmosphere means no blast wave.

 

A vacuum has no air to conduct kinetic explosive force to, so all you get is hard radiation and maybe bits of shrapnel and definitely plasma that rapidly dissipates in a cloud so fast that will miss it if you blink.

Link to comment
Share on other sites

1 hour ago, Spacescifi said:

Moar gas (thicker atmosphere) equals a more destructive blast wave generally speaking.

 

Less gas makes a blast wave that is less destructive.

 

A nuke in a vacuum is bascislly just a flash of bright light.... blink and you will miss it. Yes the radiation csn hurt if not shielded, and a direct hit would do serious heat damage besides kinetic, but overall less damage than anywhere with an atmosphere because no atmosphere means no blast wave.

 

A vacuum has no air to conduct kinetic explosive force to, so all you get is hard radiation and maybe bits of shrapnel and definitely plasma that rapidly dissipates in a cloud so fast that will miss it if you blink.

Pretty much what I was going to say, but in a vacuum, you may be underestimating the strength of the blast wave from the vaporized bomb casing. Much less than in atmosphere, but according to the pros, not insignificant. Well, at least not according to Arthur C. Clarke...

Link to comment
Share on other sites

My vision.

Most part of a nuke energy is X-rays.

The fireball is just an area of surrounding material which has absorbed this X-ray, thus has been heated and compressed, and starts to expand at ultrasonic speed.
It's also opaque for the electromagnetic radiation, so looks like a bright opaque ball.

In vacuum there is nothing to absorb the X-rays.
So, far from the objects it's a burst of invisible X-rays and quickly disappearing hot gas cloud.

If a ship is enough close to the burst, it partially absorbs the X-rays by hull,  partially lets them pass through and irradiate the crew and the equipment.
If it's more enough close, the X-rays which have been absorbed in the hull, will heat it up and make it white hot and deformed, and heat up the fluids in tanks,
or vaporize it and turn into a metal gas cloud, which is expanding like a burst and destroy the whole ship.

So, close to a in-vacuuum nuke the ship would just explode, far from it it would get the crew irradiated, the electronics damaged, the glasses probably gotten opaque (because a glass is more sensitive to radiation than a human organism).

 

Close to an airless moon surface, the X-tay flow would be absorbed by the upper layer of ground, making a bright hot spot, and vaporize it, causing an explosion across the area.
The evaporated ground gas cloud in vacuum would quickly expand and disappear, covering the area with radioactive dust.
The hot spot will be glowing for seconds, cooling from white to maroon, and cool like a glass spot, similar to the the nukes on the Earth.
The objects close to the place will be irradiated by the nuke, smashed (but less that in air) by the gas cloud of evaporated ground, heated up by the X-ray absorption and by the hot spot light.

 

Close to the Martian surface it would cause same hot spot like in vacuum, due to thin air.
Due to thin air, the X-rays will travel much farther, being absorbed by the thin "air".
The same X-ray energy as on Earth will be absorbed by the same "air" mass. And as the same mass occupies by 2..3 orders of magnitude greater volume, the gas pressure will be significantly lower, and probably not enough hot to make fireball be opaque and supersonic, and thus to run a shockwave.
So, probably it will look like a transparent glowing spehere, a burst of wind, and a bright gas cloud from the surface, causing a secondary shockwave, stronger than the thin air motion, but much weaker than on the Earth.
The said about the radiation stays same.

Unlikely a mushroom cloud will appear, as the air is too thin to form a stable toroidal cloud.
More probably, a huge toroidal dust cloud will just cover the whole area and dissipate.

 

The Venusian atmospheric pressure should make the classic fireball 4..5 times smaller, but the total energy stays same.
As the "air" density is much greater, the same air mass, which can be pushed, occupies much lesser volume. So the shockwave energy will likely dissipate at several times lesser distance.
Unlike the ocean of water (which is incompressible), the gas is compressible and viscous, so the shockwave energy will be quickly turning into the energy  of gas friction, and heating the "air" up.
So, the smaller fireball caused by the X-rays absorption, together with smaller shockwave area, should form a bubble of hot but subsonic air, compressed enough to be glowing and release the total energy as light and partially X-rays.
So, the objects at GZ would suffer from high pressure, but as they are Venusian object, they anyway should be enough strong to withstand 90 atm = 9 000 kPa.
The best shelter on the Earth () are 300..500 kPa strong. Minuteman silos are 2 000 psi ~= 10 MPa strong.
So, it will be ok with the Venusian objects, except with the one being hit directly.

The total energy being mostly released as light, will heat up the Venusian surface... Oh wait... Heat up the Venusian surface???

The mushroom cloud will form, but as the air mass will take away its energy much quicker, will be much lower.
At the same time, it will be cooling much slower due to hot air around, so probably will turn into several hot clouds lifting up and dissipating.

 

A gas giant.

Spoiler

 

Edited by kerbiloid
Link to comment
Share on other sites

I'm pretty sure there would be no significant differences between a neutron bomb in a vacuum and in an atmosphere.  If anything, the bomb would be worse as none of the neutrons would be absorbed by the atmosphere.  Such bombs are a bit specialized, damaging life and little else, so you would have to have significant life (like a population) to even notice the damage of the bomb.

Link to comment
Share on other sites

But shoemaker levy 9 was a comet which caused impact energy millions of times of the biggest nukes we have. im saying what if you were to drop a tsar bomba on jupiter or saturn or the ice giants. would the mushroom cloud expand down because there is no ground so it would be like a double mushroom cloud going both up and down?

Link to comment
Share on other sites

31 minutes ago, awsumguy76801 said:

But shoemaker levy 9 was a comet which caused impact energy millions of times of the biggest nukes we have. im saying what if you were to drop a tsar bomba on jupiter or saturn or the ice giants. would the mushroom cloud expand down because there is no ground so it would be like a double mushroom cloud going both up and down?

Fireballs rise because of the immense heat inside (hot air rises). So no, you would not get a mushroom cloud going down. The cloud "mushrooms" as it rises because the outside gets cooled by the surrounding atmosphere.

Link to comment
Share on other sites

19 hours ago, wumpus said:

I'm pretty sure there would be no significant differences between a neutron bomb in a vacuum and in an atmosphere.  If anything, the bomb would be worse as none of the neutrons would be absorbed by the atmosphere.  Such bombs are a bit specialized, damaging life and little else, so you would have to have significant life (like a population) to even notice the damage of the bomb.

A neutron bomb is just a thermonuke with inefficient containment. Thus all small thermonukes end up leaning towards "neutron bombs". In the end, achieving the high dosage needed for immediate incapacitation proved quite difficult - especially since Warsaw Pact tanks already came with applique anti-neutron shielding. In the end, the only place where thermonukes (and x-way nukes with gold tampers) got any mileage was high-altitude missile defence, precisely to increase lethality in vacuum.

Their use as instant population remover weapons is a myth, not unlike nerve gas - but at least you can laboriously decontaminate something still covered in lethal residue, whereas you can't really do anything with a structure that's been neutron-activated.

Link to comment
Share on other sites

On 4/2/2022 at 5:17 PM, awsumguy76801 said:

in a vacuum with no atmosphere

 

On 4/3/2022 at 1:35 AM, kerbiloid said:

Most part of a nuke energy is X-rays

This is the case - in (probably) Niven and Pournelle's sci-fi space battles, what they had was nukes that would detonate near a ship - but the charges were shaped in such a way as to create x-ray lasers as the actual ship-killing device.

 

For a more detailed look:

NUCLEAR WEAPON EFFECTS IN SPACE (nasa.gov)

 

Link to comment
Share on other sites

28 minutes ago, JoeSchmuckatelli said:

This is the case - in (probably) Niven and Pournelle's sci-fi space battles, what they had was nukes that would detonate near a ship - but the charges were shaped in such a way as to create x-ray lasers as the actual ship-killing device.

Actually, I recall the SDI program used nukes to generate X-ray lasers, yes. But in Footfall it generated gamma-ray lasers. 

Are they both possible, depending on the composition of the ‘spurt bombs’? No idea…

Edited by StrandedonEarth
Link to comment
Share on other sites

X-rays lasers were on the table, and highly probably still are.

A long (meters) and thin (millimeters) metal rod with the nuke energy applied from one end, makes its X-ray radiation coherent and reemits it from the opposite end in axial direction.
So, it's an X-ray collimator.
A bunch of many rods (around the targeting telescope inside) emits a bunch of thin rays mixing into one thick ray, and can hit/heat a target at ~1 000 km distance..
(I have a 1980s Soviet book from my schoolhood with elementary calculations.)

Last years I have been occasionally watching pdfs with more detailed and advanced things far beyond the elementary ones from that book.
Many (most?) of them metion both X-ray and gamma lasers, as mostly the temperature defines the spectrum of emission.

As the hit range of such device of reasonable (for 1980s tech) mass and dimensions is about 1 000 km, while ICBM trajectory is ~10 000 km long, LEO sat semi-orbit is ~20 000 km long, and HEO sat is ~36 000 km high, this means that an X-rays warhead in many cases should be first delivered to the target proximity like any other warhead, rather than just float in LEO.

Also this means that it doesn't need a close fly-by and a proper flight heading, it should just pass in hundreds of kilometers from the target and rotate with the telescope into its direction.
That's why I believe, such X-ray/gamma laser warheads are the most probable hi-tech star wars until the humanity invents an Existence Improbability Field and Virtual Annihilation Resonant Ray making them traditional weapons obsolete.

***

In turn , laser or not, the initiating nuke sends the energy in all directions, so mostly wastes it.
So, in 1980s they were often painting a hedgehog of rod bunches around the nuke, to use its energy on several targets.

It's maybe a good idea against a dense cloud of warheads, but hardly for far and standalone targets.

So, a directed nuke is an efficient source of energy for this device.

And what is the directed nuke?
It's exactly what the whole Orion project had grown from, is based on, to be propelled by and armed with.

Both berillium pusher/filler and tungsten membrane are heated by the shaped nuke explosion and concentrate the energy in the required direction.

Just in Orion and Casaba it's used to send a mechanical hit towards the pusher plate and the target respectively, while in the X-rays laser it should heat the rod bunch from the end.

So, I believe the X-ray laser is another twin project of the Orion and Casaba, and the only thing changed is the suspended pusher plate ship.
(As obviously nobody will spend hundreds of nuke charges for the reasons of pollution, cost, and proliferation in case of the ship loss, probably it will be implemented only in MiniMag Orion version, a century later.)

Alsoas the obvious tendention based on the raising accuracy is to use as lower yield as possible, the same Casba/Orion things are probably studied for hit a ground target from top and distance.

Edited by kerbiloid
Link to comment
Share on other sites

Uranus and Neptune have gravity similar to Earth and Venus.  The only problem is supercritical fluids at thousands of atmospheres pressure.  We don't know how big the rocky cores are.

Nuking the hydrogen and helium off into space sounds very wasteful.  But perhaps with most of the atmospheres removed we would have two more livable worlds... almost as easy to colonize as Venus.  

Gamma ray lasers might be fiction.  Lasers depend on mirrors.  You can generate a lot of gamma rays, but you need gamma ray mirrors to get the lasing effect for more than one pump.  Stellar corona lasers are another good way of removing gas giant atmospheres.  

Edited by farmerben
Link to comment
Share on other sites

This thread is quite old. Please consider starting a new thread rather than reviving this one.

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...