Space ship powered by exploding atomic bombs?

I remember reading a Niven-Pournelle sci-fi story about 20 years ago where the author(s) postulated that a good way to drive space ships would be to explode a series of small atomic bombs to provide thrust. Obviously it would need to be a long ship as the crew and storage would need to be shielded by a huge (concave I’ll guess) shielded, blast wall device at one end and the crew quarters etc would be at the other. IIRC I think the atomic device was exploded in space at a preset distance from the ship to give maximum thrust without destroying the blast wall.

Relative to other fuels I imagine this would have a great potential fuel/weight thrust ratio for outer space travel but is it practical?

Assuming the blast lasts as long as 30 seconds and the human body can endure 12 g’s, that’s only a speed of 2 miles per second. Only 40% of the necessary orbital velocity.

I’d heard of “Project Orion” years ago, but had no idea until recently that the U.S. government had actually semi-seriously considered the idea back in the late '50’s through the '60’s. Apparently they intended to launch this sucker from the ground (I’d always seen it before as a proposed interstellar probe, and tended to assume it would be a strictly space-to-space vehicle.) Despite the seeming daftness of the idea, there is something attractive about the idea of a 10,000 ton, 16-story-tall spaceship zipping around the Solar System, seeking out strange new worlds and so forth. They certainly were thinking big, especially compared to dinky little one- or two- or three-man “capsules”. Somehow, I have a feeling we’ll never launch a spaceship into orbit by setting off a bunch of atomic bombs (even small ones), if only for political reasons. (IIRC Niven and Pournelle had an Orion-type space battleship lift off–from the middle of a town no less!–in Footfall, but that was after Earth was invaded by aliens from another star system, which I guess would tend to loosen our inhibitions somewhat.)

Here’s a link to a history of the project by Michael Flora:

Project Orion: Its Life, Death, and Possible Rebirth

I was really thinking of ships built in orbit and using bombs in space as “fuel”.

WOW!! What a great link MEBuckner. Thanks!

Apparently everything old is new again.

There is a variation on that that NASA is considering. Using a conventional fission reactor to superheat fuel instead of burning it. They can get more heat (more thrust) by this method then burning. This idea is called nuclear engines.

Using fission explosions is another concept still far away. One design I saw was a ‘parachute’ design. The spaceship is behind the chute and the explosion happens between the chute and the ship.

21[sup]st[/sup] Century Science and Technology had an article on this a few years ago…here’s a link.

[sub]There’s also a really good article by my good friend and snowboarding buddy Colon Lowry.[/sub]

Bizerta: You don’t use just one bomb. You use a whole bunch. Just not all at once.

Project Orion proposed an absolutely HUGE vessel that would pop a-bombs out its backside like an incontinent BB gun and ride the blast waves into orbit and beyond. I understand they solved virtually every problem associated with the concept but one. Almost no-one likes the idea of setting off several (about 1 per second) nuclear devices within the Earth’s atmosphere.


Carl Sagan mentioned this concept in his “Cosmos” series. He said (at the time) that we had the capability of doing it immediately, except that the U.S. and other nations had signed a treaty banning nuclear weapons in space.

Seems a bit silly to me - space would probably be the safest place to detonate them. Nice treaty, eh? The only place we are allowed to set of nukes is here on earth!

Freeman Dyson was involved in the Orion project - I think they built a scaled down version that worked fine (using non-nuclear explosives of course). If you’re interested you’d find the details in one of Dyson’s books like “Infinite in all Directions” (he wrote a number of books - that might not be the right one)

With detonating nukes in space-- at least LEO-- that I can think of off the top of my head.

The first, and most dangerous/problematic: EMP. The electromagnetic pulse that all exploding nukes give off is especially potent (at least in theory) from a high altitude. Lots of delicate electronics (including satellites) frying over a good chunk of a hemisphere, NOT pretty.

The second would be all of the fallout that eventually has to land SOMEWHERE as it deorbits. Probably nothing more serious than long term low-grade radiation over a large portion of the earth’s surface…

I read a very cool book years ago about Freeman Dyson and his son George called The Starship and the Canoe. George goes to Canada to escape the static over a posession charge, and ends up living in a tree house he builds 100 feet up a Douglas fir tree. Later builds a canoe and travels many places not trodden by the rest of us. Quite a lot of freedom in this story; but lonliness, too. Beautiful read.

It doesn’t use bombs, but there has recently been a new development in fission-powered space propulsion.

As far as I can make out, the thrust comes directly from the fission fragments of a chain reaction occuring in a thin film of a highly fissile isotope. The thrust is likely to be low but the specific impulse extremely high.

There is also the minor :rolleyes: problem of getting nukes into space safely (IE Challenger).

I seem to vaguly remember that a nuclear powered rocket engine was built and tested in the 70s. I can’t remember what it was called though…
Anyhoo, they had a TV show like NOVA or something and they toured the test facilites. It was quite interesting because it looked like it was just abandoned when they shut it down. There were still coffee cups on desks and such, and the building interior was all some ugly 60-70s green color.

Darn, I wish I could remember more about it…but I am pretty sure they did build an engine and run it…

The NERVA (Nuclear Engine for Rocket Vehicle Aplication) Program aimed at building a nuclear engine; here’s some history of the program.

Anachronism – well, remember, in the original Orion Project they planned on getting the nuclear bombs into space by–um–well–by blowing up small nuclear bombs underneath the giant spaceship to blast it into orbit. Apparently there is actually more than a snowball’s chance in hell that this could work, from a technical viewpoint (although it was never really tested); I suppose a few bleeding-heart tree-hugging pansy liberal types might have some sort of silly environmental objection to the aforesaid launch procedure, though…

I just had to chime in with another excellent book, The Curve of Binding Energy by John McPhee. This book details Ted Taylor’s research into nuclear weapons, and is a damn good read.

Apropos of nuclear rockets, see also Project Pluto - the “Flying Crowbar”, a nuclear ramjet powered cruise missile.

The Challenger was nuked?



I assume you are not joking due to a lack of a ;).

If you are shipping nukes to space for use in space, and the craft carrying them blows up, it would probably upset a few people. Particularly anyone under it, and the above mentioned bleeding-heart tree-hugging pansy liberal types. I don’t know if being in an explosion would cause a nuclear bomb to go off, but it would be a disaster nonetheless. I gave the challenger as an example of a failed space launch.

This is a different issue than launching a ship from earth with nuclear bombs.

You might need to re-calibrate your subtle sarcasm and/or humorous/ironic asides detector.

Re MEBuckner’s “pansy” comment “I suppose a few bleeding-heart tree-hugging pansy liberal types might have some sort of silly environmental objection to the aforesaid launch procedure, though…” was not intended to denigrate environmental concerns about using atomic bombs to power a space ship. The point was that it was so obvious that this would be unacceptable to almost everyone that the “pansy” comment was humorous.

Re DaveX’s comment he is well aware the Challenger did really get nuked or that you really thought it might have been nuked but the way your question was phrased it was too big a softball to let go and he took a whack at it just for fun.