Revisiting Project Orionby Sam Dinkin
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| Dyson claimed that the cancellation of Orion was “the first time in modern history that a major expansion of human technology has been suppressed for political reasons.” |
This is a late ’50s design that has actually had its economics improve over time. The weight of 800 nuclear bombs has gone way down. For the eight terajoule (two kiloton) explosions required for the 4500-ton version that can carry 20 people to the Moon, Jupiter, and Saturn in the same trip, instead of the 900 tons of nuclear bombs at almost one ton each, there would need to be probably only 50 tons’ worth of bombs since artillery shells were subsequently developed that weighed much, much, less than what could be conceived in the late ’50s. Furthermore, an artillery shell is what is needed because the bomb is going to be shot out the bottom of the Orion ship at intervals as short as one-fourth of a second at first.
Shock absorbers have also come a long way since the 1950s. To protect the people from the huge kick of a blast, Orion envisioned huge shock absorbers designed to absorb the impulse of the 1000-ton pusher plate with the entire rest of the ship. Other versions looked at further absorption just in the crew area. My recommendation would be to put the crew on a long electromagnetic track. They could potentially be the only part of the ship that is isolated from the high-g shocks. By having a very small mass isolated from the pusher shocks, the mass of the shock absorbers could be reduced from 900 tons to something more manageable. Additional mass would need to be used to strengthen the components that would not have been exposed to high-g shocks in the old design, but I think a substantial improvement in the mass fraction devoted to shock absorption should be able to be achieved.
Cabin design, mass economization, and recycling have also been improved quite a bit in the last 50 years. That should allow us to launch more people for the same gross weight. Personally, I think it would be sexier and more popular in Japan to launch the Battleship Yamato. Or perhaps a 20,000-ton Ohio-class nuclear submarine should be delivered to the oceans of Europa.
As the engineering gets better and better the bigger you get, why was this cheap, effective technology stillborn? Not the engineering.
The politics
Is it possible that politics have evolved sufficiently to come full circle? Would Queen Isabella have quibbled about crew and onshore subjects dying in order to launch three ships to the New World?
| Bush has got NERVA, but is that enough? |
President Bush in his first term has been successively undoing many of the treaties, policies, and laws written in the last 50 years. Working backwards from negotiation dates, Bush Rejected the 1999 Land Mine Treaty and tossed out the 1997 Kyoto Treaty negotiated by the Clinton Administration, reversed the George H. W. Bush 1990 tax hike and the SDI cancellation, signed gentlemen’s agreements instead of something like the 1991 START treaty, stepped away from the 1990 Powell Doctrine, subordinated Reagan’s war on drugs and anti-Soviet policy to the war on terror, reversed Ford’s 1976 executive order banning assassinations, reversed the Nixon-era 1972 national policy on the Space Shuttle, withdrew from the 1972 ABM Treaty, reversed the 1971 NERVA cancellation, let the 1970 Clean Air Act segue into “Clear Skies”, and expanded Lyndon Johnson’s 1965 Medicare Act. He is currently working on redoing Franklin Roosevelt’s Social Security Act of 1935.
Before he gets to 1935, there are a couple of decisions I would like him to revisit. Specifically, I think he should go back to Kennedy’s famous September 1962 speech and revise it and sub in “Mars” or “Jupiter” or “Saturn” for “the Moon”. In George Dyson’s book, a nuclear rocket trip to Saturn by 1970 appears just as feasible in 1959 as Von Braun’s chemical rocket trip to the Moon “in this decade” did at that time. It looks even more lopsided now as we try to create a significant presence on the Moon and move on to Mars than when Von Braun belatedly endorsed the idea in the mid-sixties.
If Bush decided to revive the Orion project, he would also need to withdraw from the Comprehensive Test Ban Treaty of 1996 and the Partial Test Ban Treaty of 1963.
Bush has got NERVA, but is that enough? Internal combustion nuclear engines have an inherent limit. If the exhaust is too hot, it melts the rocket nozzles. This is an inherent limit in all non-pulsed designs. By using external combustion, fantastic temperatures hotter than the surface of the sun can be achieved, yet the plasma will cool sufficiently as it expands so as not to melt the pusher plate of the Orion.
Orion’s fantastic engineering is not good enough if the rocket kills people. Freeman Dyson, one of the great contributors to Orion, feels that he was decisive in getting the Orion project nixed in the 1963 Partial Test Ban Treaty. He was making the decision based on the fallout. He calculated that there would be enough fallout to kill one to ten people globally with each launch.
The morality of this is too simplistic: It kills people so let’s not do it. That would rule out just about every human transportation type. How can we balance the books?
| The morality of this is too simplistic: It kills people so let’s not do it. That would rule out just about every human transportation type. |
If something is worth a lot, then it is worth doing even if it kills people. We agree to a steady flux of deaths from the particulates and radiation released by coal-fired power plants because we want our homes heated and our refrigerators to run. One rough estimate is 100,000 deaths a year from coal-fired power plants.
Suppose we simultaneously enact a policy to cut the coal contribution to global radiation by more than we added radiation to the atmosphere with the Orion launches (for example, by taxing Orion launches and using the money to buy coal emission permits)? Well, we would be saving lives on balance. The absolute moralist nevertheless would say, “No! Just save the lives and forget the Orion launch.”
Here are a few of many reasons why to embrace the risk:
- Orion can lead to anti-asteroid operational capability decades ahead of anything else. That results in a flux of 200 fewer dead a year from the chance of the Earth population being destroyed by asteroids. Richard Posner says we should count extra because we would be saving the species.
- There are people willing to pay a lot of money to take a trip on Orion or use it to found a colony. Those people won’t pay for it (and any pollution- or flu-reducing taxes associated with using it) unless they get something in exchange. An analogy is that if you set the fines for speeding in a sports car high enough, you can use the money collected to make the roads safer and reduce the overall death rate from highway accidents, versus electronic switches that prevent each car from exceeding the speed limit.
- A trip on Orion will generate economic growth, scientific advancement, and wonder that will extend and enrich many lives in the future.
- Like a firing squad where there is a chance that everyone has a blank, it is possible that no one will die due to the Orion launch. How would the diffuse benefit of hundreds—or billions—of lives saved or improved due to success of Orion stack up to a diffuse risk?
So was Orion cancelled in a crisis involving the philosophy of economics? Perhaps. It is not clear that we have evolved all that much in this respect. So perhaps the next billion dollars that President Bush spends on the space program should be used to research the utility theory of death and sacrifice enough to convince the world to use the fabulous designs already on the shelf.