Project Orion Revisited: Is Nuclear Propulsion the Future of Space Travel?

[anorlunda]

Project Orion https://en.wikipedia.org/wiki/Project_Orion_(nuclear_propulsion)

Orion was one of most fanciful proposals ever for use of nuclear power. Basically, the spacecraft would have a thick shield at the back end, and then use a series of nuclear explosions behind the shield for propulsion. Let's say 100 nukes might get you to the Moon.

The whole idea sounded preposterous to me, yet compellingly fun. It was featured in the 1985 SF novel, Footfall by Larry Niven and Jerry Pournelle as a way to lift heavy payloads without long waits for engineering development and testing. That really did make fun reading.

Nevertheless, the idea was still preposterous. I thought that the Orion idea was dead and lost in history. So, I was surprised to read today that the idea is being revisited. But not revisited by scientists and engineers, but rather by lawyers.

My source at deliverypdf.ssrn.com says

PULSED NUCLEAR SPACE PROPULSION AND INTERNATIONAL LAW: SOME PRELIMINARY OBSERVATIONS Glenn Harlan Reynolds* & Juliet Leigh OuttenSome important questions stem from the fact that the “pulse” in pulsed nuclear propulsion is an atomic explosion, albeit a small and focused one. Among those issues are legal questions, chiefly involving the Outer Space Treaty of 1967 and the Limited Test Ban Treaty of 1963. This article will outline the nature and capabilities of pulsed nuclear propulsion, and the reasons why it may prove enormously tempting in the context of an all-out space race. It will then explore the extent to which existing space law poses barriers to this technology, and what nations seeking to employ that technology might do in response.

Nevertheless, these lawyers can't resist the temptation to try to to their own amateur engineering estimates.

When comparing these numbers to health statistics associated with commonly accepted means of transportation, the [radioactive] fallout numbers begin to look quite negligible.

It makes me think of certain superpower that I shall not name. That power has 6000 nuclear warheads, that I wish they didn't have. What to do with 6000 nukes? Maybe we could convince that unnamed leader to try to outdo Elon Musk's stunt of sending a Tesla into space and to protect his assets from seizure at the same time.

 

[hutchphd]

Of course there were some pretty good folks on the early Orion team including Freeman Dyson and Theodore Taylor. They were thinking of pretty small nukes. I assume you have seen this wonderful test footage


.

 

[DaveC426913]

...featured in the 1985 SF novel, Footfall by Larry Niven and Jerry Pournelle...

That really did make fun reading.

Wham!
Wham!
Wham!
God was knocking, and he wanted in BAD.

 

[Borek]

That power has 6000 nuclear warheads, that I wish they didn't have.

Slightly off topic: Judging from the effectivity of that power's land forces I suppose most of these warheads are useless junk.

Not that I am eager to test them in real life, but somehow I doubt both the number itself and chances they can get delivered.

 

[anorlunda]

Not that I am eager to test them in real life, but somehow I doubt both the number itself and chances they can get delivered.

Isn't that what deters the US from providing a no-fly zone? We can't afford to test the doubt.

 

[Klystron]

The essential physics behind Project Orion included impulse powered spacecraft as an alternative to chemical rockets. Nuclear bombs just happened to give the 'biggest bang' given the limits of technology. Also, Edward Teller* and other scientists appreciated the 'swords into ploughshares' aspect of repurposing devastating weapons for powering spacecraft .

Let us not disparage the importance of international law concerning nuclear weapons in space. ICBM's and bombers were originally considered a stopgap until space based weapons became feasible.** Lucky for humanity rational minds limited this concept, so far.

I bring up Niven's science fiction on that sub-forum to encourage new authors to incorporate physics and mathematics in their fiction, to explore edgy but almost achievable technology.

Recall that Robert Goddard was ridiculed for experimenting with chemical rockets not too many years before Werner von Braun hit London with difficult to intercept early rockets and cruise missiles. Skeptics should also keep an open mind.

--------------
*I roomed with Teller's cardiac nurse for a few semesters who loaned Teller's wife my copy of "Footfall" and also "Protector" while he convalesced after heart surgery in the 1980's. His reported response mirrored the OP's, ridiculous but fun read.

**attributed to USAF SAC general's retirement speech.

 

[anorlunda]

*I roomed with Teller's cardiac nurse for a few semesters who loaned Teller's wife my copy of "Footfall" and also "Protector" while he convalesced after heart surgery in the 1980's. His reported response mirrored the OP's, ridiculous but fun read.

That's an interesting connection. Of course, I heard the rumor that Teller spent the latter half of his life protesting, "I am not Dr. Strangelove," but nobody believed him. That's fun to hear, but I wonder if it was true.

 

[gmax137]

I read George Dyson's book a while back. Pretty interesting. Seems like there's less room today for wild ideas.

EDIT:
https://www.amazon.com/dp/0805059857/?tag=pfamazon01-20

 

[hutchphd]

That was a good read. His dad always seemed like such a professorial type...interesting career

 

[bob012345]

The size of nuclear weapons should be limited to hand grenades.

 

[Klystron]

That's an interesting connection. Of course, I heard the rumor that Teller spent the latter half of his life protesting, "I am not Dr. Strangelove," but nobody believed him. That's fun to hear, but I wonder if it was true.

Strange connection, indeed. My roommate developed a good relationship with Teller's family while at the medical center. She said he was a difficult but entertaining patient who sang and joked with staff. She mentioned "Dr. Strangelove" jokes circulating around Stanford MC but not with her patient. She loved imitating his Hungarian accent and old-world mannerisms.

I think Teller was more concerned in later life with how he was portrayed in biographies and documentaries about Robert Oppenheimer, implying that Teller 'stabbed Oppie in the back' with the AEC damaging Oppenheimer's reputation and career. Fascinating personalities and history.

 

[256bits]

Isn't that what deters the US from providing a no-fly zone? We can't afford to test the doubt.

Not really.
Airplanes flying can be shot down.
For an effective NO Fly Zone, an area the size of ?? would have to be eliminated of all land bases/areas capable of locating and directing fire at an airplane.
How large is ??, It would have to include a considerable amount of territory on the sides adjacent to the border enclosing the area of NO Fly Zone.
Mobile missile launchers, though, could be anywhere, and remain undetected.

Some friendly fire would necessarily occur as the people doing the No Fly would not be in direct communication with friendly forces on the ground who could, by chance, make an incorrect assumption of friend or foe.

The casualties to be assumed by the NO fly people/aircraft is indeterminate, and perhaps not worth the risk.
In addition, especially, when the foe, seeing his territory being attacked, would reply in kind, perhaps in an indiscriminate manner with conventional ballistic weapons at nearby friends of the No fly People.

Note the non-mention of nuclear weapons even being considered at this point of the escalation of conflict on towards outlying areas.
A NO Fly Zone would actually bring the usage of nuclear weapons closer to fruition if a side becomes more desperate in their decision making. And/Or, if a newly attacked angry side, loses their cool and is going to teach the other side a hard earned lesson.

There is no let's do A, then B, and C will happen in conflict in a nice orderly fashion.

 

[Klystron]

IMS Freeman Dyson or a project colleague pointed out an advantage of detonating hydrogen bombs in space as propellant compared with 'super bombs' intended as weapons. Larger bombs on Earth provide diminishing returns (area destroyed) compared with larger explosions channeled as a space drive. As other members have posted, smaller 'cleaner' bombs with less radioactive residue provide a more practical drive candidate.

My takeaway from studying Project Orion and declassified nuclear space drive papers precluded manned vessels, even given copious radiation shields and mechanisms to counter high 'G-forces'. Practical nuclear drives were expected for use in space far from Earth to move or nudge inert cargo such as large chunks of water ice, machinery or supplies for human voyagers traveling in safer 'conventional' craft.

One supposes hydrogen bombs of any size as propellant only provide a theoretical stopgap until controlled sustained fusion becomes practical to use as a space drive. Optimists can point to ion drives as a distant offshoot of Orion research. Putt-putt instead of wham-wham?

 

[Hornbein]

Of course there were some pretty good folks on the early Orion team including Freeman Dyson and Theodore Taylor. They were thinking of pretty small nukes. I assume you have seen this wonderful test footage


.

Their friend Richard Courant allegedly said, "This is not nuts. This is supernuts."