Projest Orion began in 1958 at General Atomics in San Diego. The company is now a subsidiary of defense giant General Dynamics.
http://www.astronautix.com/articles/probirth.htm"At a time when the U.S. was struggling to put a single man into orbit aboard a modified military rocket, Taylor and Dyson were developing plans for a manned voyage of exploration through much of the solar system. The original Orion design called for 2000 pulse units, far more than enough to attain Earth escape velocity. "Our motto was 'Mars by 1965, Saturn by 1970'", recalls Dyson "
"One can imagine that Orion could be used as a weapon platform, in a polar orbit so that it would eventually pass over every point on the Earth's surface. It could also protect itself easily, at least against attacks by small numbers of missiles. However, this idea has the same disadvantages as the early bomb-carrying satellite proposals. Terminal guidance would have been a problem (assuming that hardened, high-value installations were the intended targets), since the technology for steering missile warheads accurately had not yet been developed. Both the U.S. and the Soviet Union were deploying missiles that were capable of reaching their targets in fifteen minutes with multi-megaton warheads, making orbiting bomb platforms irrelevant."
"A crisis came in late 1959, when ARPA decided it could no longer support Orion on national-security grounds. Taylor had no choice but to approach the Air Force for funds. It was a hard sell. A common reaction from both military and civilian officials is displayed by the quote: "...you set off one big bomb and the whole shebang blows up."(34) The Air Force finally decided to take on Orion, but only on the condition that a military use be found for it. "
"Unfortunately, the Orion concept is inherently "dirty" because it uses fission fuel. It is also inefficient; this is acceptable only because of the vast amounts of energy available. A much better alternative is fusion, since a fusion rocket would not leave a wake of heavy radioactive ions."
Orion will rise!
November 16, 2001
"The radioactive, fissile material taken from those (Orion) warheads posed almost-eternal security risks of its own. It would have to be guarded with 100 percent perfect security indefinitely to prevent it falling into the hands of terrorists, criminals or political extremist fanatics.
Nor could the fissile material once manufactured ever be rendered down into more harmless compounds or other elements. And even if it was protected safely, the environmental and contamination dangers from it would also last at the very least thousands, perhaps even hundreds of thousands of years, given the slow half-life, radioactive decay rates of the lethal elements involved.
Dyson and Taylor proposed a radical solution to these problems. The atomic weapons could only be used up and totally rendered useless if they were actually exploded and they proposed to do this with lots of them. This would happen not on the earth or in the main atmosphere, but -- mainly -- in the far reaches of outer space.
Dyson and Taylor proposed to explode atomic bombs at regular intervals at very short distances behind a specially designed space ship in order to propel it to the Moon and other planets in the Solar System far more quickly and cheaply than chemical-fuel rockets could ever do so."
"Project Orion is a monument to those who once believed, or still believe, in turning the power of these weapons into something else." George Dyson
http://www.whitchurch-school.org.uk/generalinf/newsitems/nasaproj/Orion1.As for the fusion fuels:
Deuterium is abundant as it can be extracted from all forms of water. If all the world's electricity were to be provided by fusion power stations, Deuterium supplies would last for millions of years.
Tritium does not occur naturally and will be manufactured from Lithium within the machine.
Lithium, the lightest metal, is plentiful in the earth's crust. If all the world's electricity were to be provided by fusion, known reserves would last for at least 1000 years.
Once the reaction is established, even though it occurs between Deuterium and Tritium, the consumables are Deuterium and Lithium.
THERMONUCLEAR FUSION RESEARCH COULD RESULT IN NEW WEAPONS AND GREATER PROLFERATION DANGERS July 15, 1998
Institute for Energy and Environmental Researchhttp://www.ieer.org/latest/fusn-pr.html"Pure fusion weapons have long been a dream for nuclear weapons designers. Present-day thermonuclear weapons need plutonium or highly enriched uranium to set off the hydrogen-bomb part," said Dr. Arjun Makhijani, principal author of the report and president of IEER. "But pure fusion weapons would not need either of these fissile materials. They would produce little fallout. They could be made very small or very huge. And the research involves interesting scientific challenges."
However, pure fusion weapons would present far greater nuclear proliferation dangers since the acquisition of highly enriched uranium or plutonium is currently the main obstacle to proliferation. By contrast, deuterium and tritium, the forms of hydrogen used in fusion research and weapons, are less difficult to make. Verification would also be more difficult. Most importantly, fusion weapons would likely lower the threshold for nuclear weapons use, because of their smaller size and lack of fall-out, the report said."
For example, 10 grams of Deuterium which can be extracted from 500 litres of water and 15g of Tritium produced from 30g of Lithium would produce enough fuel for the lifetime electricity needs of an average person in an industrialised country.
MAIN FINDINGS AND RECOMMENDATIONS
Summary of Findings:
The scientific feasibility of pure fusion weapons has not yet been established. Until recently, there were no devices that could establish such feasibility.
Major advances in the last decade in plasma physics and in various manufacturing technologies have opened up new possibilities for pure fusion weapons.
Three major technologies could contribute to the establishment of the scientific feasibility of pure fusion weapons, and other weapons that do not require fission triggers: (i) inertial confinement fusion programs designed to achieve ignition (ii) the joint Magnetized Target Fusion program at Los Alamos (US) and Arzamas-16 (Russia), and (iii) non-fission methods of generating intense x-rays, such as the wire array z-pinch program at Sandia Lab.
Once ignition has been demonstrated at a laboratory level, it will be difficult to contain the development of pure fusion weapons. Fusion weapon proliferation controls will be far more difficult than with fission weapons because the materials are not currently under the same level of international control and because more of the relevant literature is non-classified.
Devices that use high explosives as part of the driver pose special dangers because they could be converted to practical weapons with less difficulty once feasibility is established.
There is no technical basis on which laboratory thermonuclear explosions can be excluded from the ban on all nuclear explosions under the Comprehensive Test Ban Treaty (CTBT).
The US and French laser fusion facilities known as NIF and LMJ are designed to create fusion explosions. Therefore, these facilities and all others so designed appear to be illegal under the CTBT.
Recommendations:
Construction of the National Ignition Facility at Livermore, California, the Laser Mégajoule project in France and planning of all other explosive research facilities designed to achieve thermonuclear ignition should be stopped.
The joint use of high explosive drivers and tritium fuel in fusion research should be banned.
The next CTBT conference should issue a formal opinion explicitly including laboratory thermonuclear explosions within the prohibition of nuclear explosions in Article I of the CTBT.
Magnetized Target Fusion experiments that would achieve ignition should be stopped.
The nuclear weapons states should declare formally that they are not going to design new nuclear weapons. As part of this declaration, they should explicitly renounce the development of pure fusion weapons and all other weapons that do not require fission triggers.
A widespread public debate on the disarmament and non-proliferation consequences of pure fusion weapons is needed to forestall the emergence of serious new problems.