# What Would prevent Us From Buildinga Nuclear Bomb Pulse-Jet Rocket? **URL:** \ **Category:** Factual Questions\ **Created:** [August 28, 2015, 12:36pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164 "2015-08-28T12:36:52Z")\ **Posts on this page:** 15\ **Page:** 1
**Author:** ![ralph124c](https://avatars.discourse-cdn.com/v4/letter/r/8797f3/32.png) [@ralph124c](https://boards.straightdope.com/u/ralph124c)\ **Post date:** [August 28, 2015, 12:36pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/1 "2015-08-28T12:36:52Z")
As far as i can see, if we are to have manned exploration of space (beyond the moon), our present chemical rockets won’t do. They are too expensive, too dangerous, and too slow. The idea of using nuclear bombs to propel a spaceship was c\developed in the 1960s, it was judged feasible at that time. of course, the idea of setting off nuclear bombs in the earth’s atmosphere is not popular. Suppose the ship was built in earth orbit? Would it then be safe to use? ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [August 28, 2015, 1:10pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/2 "2015-08-28T13:10:31Z")
> [@ralph124c](#): > > As far as i can see, if we are to have manned exploration of space (beyond the moon), our present chemical rockets won’t do. They are too expensive, too dangerous, and too slow. The idea of using nuclear bombs to propel a spaceship was c\developed in the 1960s, it was judged feasible at that time. of course, the idea of setting off nuclear bombs in the earth’s atmosphere is not popular. Suppose the ship was built in earth orbit? Would it then be safe to use? Well, you could, although the idea of “seeding” the upper atmosphere with lots of highly radioactive dust isn’t much more appealing to me that setting it off in the atmosphere would be. And putting the thing in orbit to begin with is overlooking one of the things that made the idea so attractive in the first place – it provides a way to lift all of your payload efficiently out of Earth’s gravity well in one big shot. With your craft in orbit, you still have to get your payload up into orbit using conventional rockets. Unless they get that Space Elevator (maybe that newfangled inflatable one) working in time. Orion-type nuclear lifters figure in some science fiction. Larry Niven and Jerry Pournelle have one in _Footfall_. And your only-in-space version almost made it into the movies. Kubrick was considering showing the interplanetary craft _Discovery_ (the one with HAL on board) being propelled by nuclear explosions in _2001_, but wisely (in my mind) decided against it. It looks classier as it is. When Peter Hyams showed us the engines on the Discovery firing in _2010_, they looked decided non nuclear-bomb-like. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [August 28, 2015, 1:21pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/3 "2015-08-28T13:21:46Z")
In addition, there was concern that if you set off nukes anywhere in space within the Earth’s magnetosphere, the fallout would be channeled to the Earth’s magnetic poles, contaminating those areas. ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [August 28, 2015, 2:05pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/4 "2015-08-28T14:05:13Z")
You’d also run afoul of several treaties, setting bombs off in space. I don’t think those treaties distinguish between peaceful and violent uses. ---
**Author:** ![Reno\_Nevada](https://avatars.discourse-cdn.com/v4/letter/r/6f9a4e/32.png) [@Reno\_Nevada](https://boards.straightdope.com/u/Reno_Nevada)\ **Post date:** [August 28, 2015, 4:50pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/5 "2015-08-28T16:50:50Z")
Another problem is that if you build the Orion in orbit, and fuel it by building the bombs on Earth and lifting them into orbit via chemical rockets, if any of those chemical rockets suffer a catastrophic failure in the lower atmosphere, the radioactive payload of the bombs will be scattered around. Rocket launches are far from 100% reliable. ---
**Author:** ![Habeed](https://avatars.discourse-cdn.com/v4/letter/h/a587f6/32.png) [@Habeed](https://boards.straightdope.com/u/Habeed)\ **Post date:** [August 28, 2015, 5:14pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/6 "2015-08-28T17:14:09Z")
CalMeacham is right on. An Orion spacecraft has to be enormous and very heavy, to tolerate the stress from setting a nuke off near the pusher plate. This is very difficult and impractical to put into orbit without using nukes from the ground. If it took, for example, 1000 Saturn V launches to launch all of the components and assembly tools to build the pusher plate, you could build much lighter spacecraft using other designs and go to other planets directly instead with 1000 launches worth of stuff. Another factor is the pusher plate has to be one homogenous piece to tolerate the stress of each nuke going off, yet it is too big to launch in one place. So you’d have to manufacture it in orbit…which means launching the machinery to do said manufacturing which is very very heavy. So if you aren’t willing to launch from the ground and just eat the extra cancers and radioactive fallout plume, it’s not a good solution. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [August 28, 2015, 5:30pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/7 "2015-08-28T17:30:17Z")
Another thing occurred to me – although Electrmagnetic Pulse phenomena from ground nuclear explosions results from interactions with atoms in the atmosphere, you can still get an EMP even with space detonations due to interactions with the Earth’s magnetic field. This isn’t theoretical – it’s been observed in early high-altitude nuclear blasts. So even if you set off your propulsive nukes in space, you’ll be in trouble, generating EMPs that will affect both ground equipment and satellite systems. > **[Nuclear electromagnetic pulse](https://en.wikipedia.org/wiki/Nuclear_electromagnetic_pulse)** > > A nuclear electromagnetic pulse (nuclear EMP or NEMP) is a burst of electromagnetic radiation created by a nuclear explosion. The resulting rapidly varying electric and magnetic fields may couple with electrical and electronic systems to produce damaging current and voltage surges. The specific characteristics of a particular nuclear EMP event vary according to a number of factors, the most important of which is the altitude of the detonation. > The term "electromagnetic pulse" generally excludes ... > **[Electromagnetic pulse](https://en.wikipedia.org/wiki/Electromagnetic_pulse)** > > An electromagnetic pulse (EMP), also a transient electromagnetic disturbance (TED), is a brief burst of electromagnetic energy. The origin of an EMP can be natural or artificial, and can occur as an electromagnetic field, as an electric field, as a magnetic field, or as a conducted electric current. The electromagnetic interference caused by an EMP can disrupt communications and damage electronic equipment. An EMP such as a lightning strike can physically damage objects such as buildings and ai... ---
**Author:** ![eburacum45](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/eburacum45/32/8690_2.png) [@eburacum45](https://boards.straightdope.com/u/eburacum45)\ **Post date:** [August 28, 2015, 9:18pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/8 "2015-08-28T21:18:15Z")
This would make a nice aurora. If I recall correctly, the early communication satellite Telstar was disabled by a high-level test of this sort. > **[Telstar | In service](https://en.wikipedia.org/wiki/Telstar#In_service)** > > Telstar 1 relayed its first, and non-public, television pictures—a flag outside Andover Earth Station—to Pleumeur-Bodou on July 11, 1962. Almost two weeks later, on July 23, at 3:00 p.m. EDT, it relayed the first publicly available live transatlantic television signal. The broadcast was shown in Europe by Eurovision and in North America by NBC, CBS, ABC, and the CBC. The first public broadcast featured CBS's Walter Cronkite and NBC's Chet Huntley in New York, and the BBC's Richard Dimble That eve... ---
**Author:** ![Lucas\_Jackson](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lucas_jackson/32/303_2.png) [@Lucas\_Jackson](https://boards.straightdope.com/u/Lucas_Jackson)\ **Post date:** [August 29, 2015, 1:19am UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/9 "2015-08-29T01:19:03Z")
First let me proclaim my ignorance. Now, how would you overcome the G forces associated with the extremely quick acceleration. ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [August 29, 2015, 2:29am UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/10 "2015-08-29T02:29:26Z")
> [@White SIFL](#): > > First let me proclaim my ignorance. Now, how would you overcome the G forces associated with the extremely quick acceleration. To build an Orion it has to be massive…I mean REALLY massive. Like bigger than the biggest air craft carrier. With a huge pusher plate. So, you won’t get extremely quick acceleration or a large G load. It would be more like flying on a V-1 buzz bomb with it’s pulse jet. [QUOTE=CalMeacham] Another thing occurred to me – although Electrmagnetic Pulse phenomena from ground nuclear explosions results from interactions with atoms in the atmosphere, you can still get an EMP even with space detonations due to interactions with the Earth’s magnetic field. This isn’t theoretical – it’s been observed in early high-altitude nuclear blasts. [/QUOTE] Wouldn’t it be directional, since the blast is directional? Also, presumably you could shield the electronic equipment on the ship from the EMP…the military has been able to shield sensitive equipment for a while. The very think pusher plate could be threaded with copper or some other things to protect the electronics and crew. Probably a good idea not to launch the things from the Earth though, as noted. 😛 I don’t see any technical show stoppers to building an Orion…it’s probably our best option if we ever need something really big to go really fast into space, though I seriously doubt that anything that important will come up before we can build something better. ---
**Author:** ![MEBuckner](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mebuckner/32/2896_2.png) [@MEBuckner](https://boards.straightdope.com/u/MEBuckner)\ **Post date:** [August 29, 2015, 2:48am UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/11 "2015-08-29T02:48:50Z")
> [@XT](#): > > To build an Orion it has to be massive…I mean REALLY massive. Like bigger than the biggest air craft carrier. With a huge pusher plate. Not necessarily. The [very smallest proposed design for an Orion-type spacecraft weighted in at a svelte 880 tons](https://en.wikipedia.org/wiki/Project_Orion_%28nuclear_propulsion%29#Sizes_of_Orion_vehicles). That would have been more of a prototype/proof-of-concept test vehicle, but even the “base” design was still “only” 4,000 tons. (One thing, “nuclear explosion” doesn’t _have_ to mean Tsar Bomba, or even Hiroshima–the [very smallest-yield warheads had extremely low yields](https://en.wikipedia.org/wiki/Davy_Crockett_%28nuclear_device%29); 1o to 20 tons–not kilotons–TNT-equivalent. I mean, “small” for a nuclear warhead.) Admittedly, Orion spaceships do scale up really fast; the biggest proposed designs had a diameter of 400 meters and weighed in at a whopping _8,000,000_ tons–I dunno how _tall_ it would be (or long, or whatever), but that’s definitely got me humming the “Imperial March” from _Empire Strikes Back_. ---
**Author:** ![Siam\_Sam](https://avatars.discourse-cdn.com/v4/letter/s/d78d45/32.png) [@Siam\_Sam](https://boards.straightdope.com/u/Siam_Sam)\ **Post date:** [August 29, 2015, 2:54am UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/12 "2015-08-29T02:54:36Z")
> [@Chronos](#): > > You’d also run afoul of several treaties, setting bombs off in space. I don’t think those treaties distinguish between peaceful and violent uses. This. I recall Carl Sagan mentioning this regretfully in his book _Cosmos_. Can’t recall if it was brought up in the TV series. ---
**Author:** ![XT](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/xt/32/456_2.png) [@XT](https://boards.straightdope.com/u/XT)\ **Post date:** [August 29, 2015, 2:59am UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/13 "2015-08-29T02:59:50Z")
> [@MEBuckner](#): > > Not necessarily. The [very smallest proposed design for an Orion-type spacecraft weighted in at a svelte 880 tons](https://en.wikipedia.org/wiki/Project_Orion_%28nuclear_propulsion%29#Sizes_of_Orion_vehicles). That would have been more of a prototype/proof-of-concept test vehicle, but even the “base” design was still “only” 4,000 tons. (One thing, “nuclear explosion” doesn’t _have_ to mean Tsar Bomba, or even Hiroshima–the [very smallest-yield warheads had extremely low yields](https://en.wikipedia.org/wiki/Davy_Crockett_%28nuclear_device%29); 1o to 20 tons–not kilotons–TNT-equivalent. I mean, “small” for a nuclear warhead.) > > Admittedly, Orion spaceships do scale up really fast; the biggest proposed designs had a diameter of 400 meters and weighed in at a whopping _8,000,000_ tons–I dunno how _tall_ it would be (or long, or whatever), but that’s definitely got me humming the “Imperial March” from _Empire Strikes Back_. Good point, though of course you’d scale down the yield if you scaled down the ship, so I think you still wouldn’t get massive acceleration (also, one of the points if making the things really really big is it provides more shielding for the crew, so not sure how well that would work scaling back too much). The point is to create a ship that is usable, not one that is going to turn the crew into paste. ---
**Author:** ![Habeed](https://avatars.discourse-cdn.com/v4/letter/h/a587f6/32.png) [@Habeed](https://boards.straightdope.com/u/Habeed)\ **Post date:** [August 29, 2015, 4:42am UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/14 "2015-08-29T04:42:18Z")
As for EMP, this was extensively researched during the cold war, and a lot of the equipment from that era is EMP resistant. It’s a relatively simple thing to shield against : 1. Faraday cage around the electronics 2. There’s this wire mesh guarded “U-bend” where the antenna enter the box containing the electronics that somehow blocks most of the EMP. 3. Some kind of fuse or shunt so that if the antenna experiences a large voltage transient, it won’t fry the electronics. As you can imagine, anyone who can build killer robots could shield a robot’s control system using these and other methods. EMP probably won’t harm the killbots of the future. ---
**Author:** ![Lumpy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lumpy/32/446_2.png) [@Lumpy](https://boards.straightdope.com/u/Lumpy)\ **Post date:** [August 29, 2015, 4:46pm UTC](https://boards.straightdope.com/t/what-would-prevent-us-from-buildinga-nuclear-bomb-pulse-jet-rocket/729164/15 "2015-08-29T16:46:16Z")
> [@White SIFL](#): > > First let me proclaim my ignorance. Now, how would you overcome the G forces associated with the extremely quick acceleration. Really, REALLY big shock absorbers: [http://pre10.deviantart.net/f4a9/th/pre/i/2015/216/4/a/michael\_by\_william\_black-d8eudqd.jpg](http://pre10.deviantart.net/f4a9/th/pre/i/2015/216/4/a/michael_by_william_black-d8eudqd.jpg)