Yeah--I wish I could be optimistic...but I'm not very either. >Shrug<

We still have opportunities to not end up like the dinosaurs.

"...the Dinosaurs went extinct because they did not have a space program. If we go extinct because we don't have a space program, it serves us right!..."---Larry Niven.

"The National Aeronautics and Space Administration is scrambling to come up with a new budget proposal to placate congressional critics as senior members of the House Appropriations Committee say that White House's plan for the agency won't fly on Capitol Hill."


WSJ link


"Fifty percent (50%) of Americans now say the United States should cut back on space exploration given the current state of the economy, according to a new Rasmussen Reports national telephone survey."


poll report


U.S. Human Spaceflight:
The FY11 Budget and the Flexible Path
A Space Policy White Paper
Edward F. Crawley
David A. Mindell
Massachusetts Institute of Technology
April 2010

Yes, I also agree there's no mention of nuclear and space in the same breath. 
(Russians more apt to mention nuclear and space than U.S.) when referring to beyond LEO space operations.
The same for the word 'reusable' as if it's cool that hardware should be relegated to crash on some terrain or burned up and dumped lying at the bottom of some ocean or flying around some useful orbit adding to the space debris problem. EELV is fine when put into context when used to engineer hardware to mission when applicable at launch. Ground launch is the biggest and most sensitive to energy and hardware usage in the short term. In-space operations is another in the long term both need components in mission architecture that require reusability at least on business plans for sustainable space operations in a commercial sense.
The error is these new space plans and policies (Obama space) rely too much on disposable.

-- Edited by NUKE ROCKY44 on Sunday 11th of April 2010 09:13:47 PM

The problem with letting private industry taking over the space program even if you believe in private industry is that they are looking for a quick buck and would not be interested in long term investments. Take helium 3 mining on the moon for example. It would take about 20 years to get this infrustructure up and running and no private company will wait that long for a return on investment. However once the concept is proven there is nothing wrong with getting private companies involved at a later time.

Also another problem is that the Constellation program is just a remake of the Apollo program and the citizens want a more exciting space program such as manned missions to Mars and Saturn rather than boring missions to the Moon. However only Orion thermo nuclear fusion pulse rockets launched from Earth will ever make this technology affordable and the only fuel that the environmentalists will allow to be exploded in the atmosphere with the least amount of protests would be Helium 3 which produces no radiation but is only available on the Moon and the gas planets.

It may seem like a pain going all the way to the Moon or Saturn to get clean green fuel however for Man to evolve he must learn to colonize other planets so this is why the carrots are always far away but still within Man's reach.

As far as the practicality of nuclear fusion rocket propulsion only contained and controlled nuclear fusion has been ellusive because it takes more energy to magnetically control the explosion than the net gain. However uncontained and uncontrolled nuclear fusion has been demonstrated by the hydrogen bomb which can be harnessed with a classic Orion nuclear pulse drive. Although a helium 3 bomb may never have been demonstrated it may be because there is no military use for such a radiation free device rather than it being difficult to build. Therefore if such a device could be built economically it would overcome the main objections of an Orion launch which would be radioactive fallout that even a theoretical pure fusion hydrogen bomb would produce.


The whole philosophy of the theoretical physicist is that by observations of quantum mechanics these principles can also be applied to the inventions of technology in that we can make quantum leaps in technological advancement without going through a step by step evolutionary development. A rejection of the possibility of quantum leaps means a suppression of a major expansion of technology which happened when the Orion project was cancelled. A concrete example of this is when the Wright brothers went from being bicycle mechanics to inventors of a motorized airplane when common sense evolutionary development suggested that they should have first invented the motorcycle.

Although a gradiose space program seems at first an easy target for budgetary cuts the fact is that economies of scale kick in and the result is a much more affordable space program. A nuclear rocket may at first seem like a boondoggle however look at how much money that could have been saved if the International Space Station could have been launched in one shot at a fraction of the cost that dozens of chemical rocket launches required.

One thing is for sure and that is that He-3 fusion will won't be available during the time frame that was address at the April 15 space conference, i.e. the next 20 years or so. 

It is true that as the tritium decays to He-3 the effectiveness of bombs goes down.  One key point to keep in mind is the purpose of the T-D reaction in the primary is to produce neutrons rather then add to the energy of the explosion in anyway.  When you have a D-He3 collision you don't produce a neutron.  Also, as the amount of T is reduced you have less neutrons and all of the collisions with He-3 just waste the D's time. 

I'm not exactly sure what Androbot's concept is.   At some points he was discussing laser fusion and other points perhaps discussion some thing more like "classic orion" with this particular nuclear pulse device (NPD).  It is interesting to note that the first thermonuclear device, Ivy Mike, was based on liquid deuterium rather than lithium-deuteride.  This does leave open the question for the feasibility of thermonuclear devices pased on the fusion of He-3.  Note that the D-He-3 reaction is in a more favorable range than D-D. 

It is claimed that abut 75% of the Mike yield was from fission of the tamper rather then the fusion reaction.  One would think that a significant fraction of the remaining 25% would be D-He3 driven.  Maybe 40% of the fusion or 10% of the total yield.  So if we used D-He3 as the fusion reactant we would have a one megaton yield rather than a 10 megaton yield.  Of course the military would have little use for such an impractical bomb.  Pure He-3 would push the yield down even further.  One might also consider Boron-Hydrogen reaction for a NPD.  The problem is that for getting approval of environmentalists any of these would have fission yield as well due to primary and sparkplug.  Also the issue of scaling down would increase the percentage of fission yield greatly.  It also goes against the comprehensive test ban.

This aside I think that for spacecraft of the western democracies we are stuck with the chemical fuels for below LEO.  This is unless propulsion based on techniques of the know physical principles arrives, i.e. sci-fi space drives.  If you go to concepts such has I've been laying out on other posts your can get very improved economies to achieve LEO.  In fact orbital fuel depots could make this practical for GEO and TLI.  Nuclear thermal rockets could improve the results for these missions. 

I'm still very impressed with the long term potential of VASIMR powered by a space nuclear reactor for mission beyond the moon.  While the early solar powered VASIMR using argon gas and solar panels can produce a few thousand seconds of Isp.  By going to hydrogen and nuclear power values as high as 30,000 sec are possible.  When you consider that fusion might give 600,000 sec or so that isn't bad.  Fusion is a much larger technological leap.  It will ultimately plan a role in space propulsion but a lot of research will have to come first.

-- Edited by John on Sunday 18th of April 2010 01:28:36 PM

As far as duds go the universe is filled with red giant stars which are stars that have burned up their supply of hydrogen and are forced to burn helium as that is the only fuel that is left.

And yes I stated a concept of a laser ignited pure hydrogen fusion Orion drive however even if that technology were possible it would result in a cancer death toll of one person per launch because even a pure fusion hydrogen bomb creates radiation. Although this would be a lesser risk than other industries it still would be psychologically unacceptable to the environmentalists who would claim that even one death is one death too many.

So other than using costly and futuristic attempts to contain the radiation the only choice we have for the rebirth of Orion is using helium 3 as a fuel which would allow an Earth based launch using atomic explosions with no radiation. Thus we satisfy the rational objections of the environmentalists although irrational objections will never be satisfied and one is to expect that an Orion launch will generate heavy protest. Also the spirit of the atmospheric test ban treaty will be preserved because the original intent of the treaty was to prevent fallout and to prevent testing of weapons and the militarization of space. A helium 3 launch produces no fallout, is worthless as a weapon or even a weapons tester because it requires a multi-billion dollar laser to achieve ignition so it does not promote the militarization of space and it does not carry a dangerous cargo of radioactive plutonium which could be a danger if there is a launch failure. However technically the letter of treaty will be violated because the treaty forbids atomic explosions in space even for peacefull purposes.