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23 May 2012, 1:09 pm

I hear a lot of *buzz* in the media about private companies(like SpaceX), building launch vehicles as well as manned (sub)orbital vehicles for human spaceflight. A lot of people are impressed, but what I'm not enthused about is the fact that I do not see any new faster propulsion technology being developed! They're just using the same old chemically powered rocket motors. But that begs the question: Does government red tape prevent private companies from R&D of Nuclear Propulsion for spacecraft? Or maybe it's just a question of the money involved..........Or both.

Discuss....



blauSamstag
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23 May 2012, 1:58 pm

I don't buy the concept that the private sector always does a better job. I think governments have a responsibility to foster pure research. I'm biased because my dearly departed uncle was a government physics researcher, and I know that the whole world benefits from the derivatives of the research he was involved in and the experiments he designed.

I'm also fully aware that NASA contracts out most of the nuts and bolts anyway. A lot of jobs were lost in Utah when the shuttle program ended.

However, I think what is currently preventing the private contractors from developing new propulsion systems is the whole question of economy for the task at hand. Chemical rockets are a pretty effective way to cut through the atmosphere and escape the gravity well.

Nuclear propulsion becomes more interesting once you are out of the gravity well, but currently NASA isn't contracting that out.

Except for the fact that most of our government research satellites were probably built by Lockheed.



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23 May 2012, 2:35 pm

I think this is all BS. In space there would be no electomagnetic field to prevent the harmful particles from the sun. The passengers could come back with cancer and sue the private space flight companies.



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23 May 2012, 2:38 pm

Robdemanc wrote:
I think this is all BS. In space there would be no electomagnetic field to prevent the harmful particles from the sun. The passengers could come back with cancer and sue the private space flight companies.


With a decent propulsion system a ship could be built with a shielded portion to go to when there is a CME from the Sun. Think of it as a Panic Room in space.

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23 May 2012, 2:59 pm

The private sector may be able to really 'make things happen' when we have the capacity to mine asteroids in a profitable manner. Previous to that though it'll likely be little more than short jumps to LEO for tourism which is a rather limited incentive.


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23 May 2012, 3:11 pm

Is it going to be safer than pass shuttle missions?


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23 May 2012, 3:28 pm

AspieRogue wrote:
I hear a lot of *buzz* in the media about private companies(like SpaceX), building launch vehicles as well as manned (sub)orbital vehicles for human spaceflight. A lot of people are impressed, but what I'm not enthused about is the fact that I do not see any new faster propulsion technology being developed! They're just using the same old chemically powered rocket motors. But that begs the question: Does government red tape prevent private companies from R&D of Nuclear Propulsion for spacecraft? Or maybe it's just a question of the money involved..........Or both.

Discuss....


The issue is more that there's no demand for better propulsion systems-both conventional and ion rockets have sent craft to the moon. Manned craft have an upper limit on acceleration (you don't want to squish the passengers!) but no practical limit on speed once they're out of the atmosphere, so slow acceleration, high duration engines (ion engines) are probably more practical than nukes. Now a nuclear reactor could drive your ion motor, but that's when you'd run into red tape-lots of special interest groups would not want a nuclear reactor flying right over them with NASA's recent safety record.



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23 May 2012, 3:40 pm

Private companies are taking the burden from NASA so they can focus on better technology for further missions. The VASIMIR engine however does represent a good avenue for the future of long distance space flight.


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23 May 2012, 3:59 pm

It's a great idea. NASA cannot afford to own and operate multiple launch systems. That's reality. Better if the same rocket that carries cargo and crew to ISS is also used for private spaceflight, satellite launches, etc. So the government doesnt have to maintain the system when it doesnt need it. NASA is currently focused on building a Saturn V class rocket designed for exploration missions beyond Earth. To launch it to the station for crew exchange and cargo resupply would be impractical and wasteful.

Faster travel is nowhere close and NASA is likely spending nothing on it. The tech development budget was slashed by Congress. VASIMR will just be another thruster for the forseeable future. If we do Mars in the 2030s or 2040s it will likely be with a nuclear thermal rocket, as was the plan in the 60s-70s.

Ad Astra is developing VASIMR privately but it's just a thruster for now. To get fast travel you'd need tremendous amounts of power, which we can't do at the moment.

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Is it going to be safer than pass shuttle missions?


Should be due to the escape rockets. Shuttle didnt have that. But space is always high risk. People will die, as with airplanes.



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23 May 2012, 4:12 pm

My guess is that private companies will be good at what they're doing now which is refining existing technology.

Research into new propulsion methods, though, is more research than engineering and isn't likely to have near-term profitability. Ever see those blooper reels of all the NASA rockets in the 1950's or 1960's that blew up? SpaceX and all are benefiting from all the government spending on those failures. If a private company had that many failures I'd expect their investors to lose confidence pretty quickly. SpaceX had 2 failures IIRC and if the 3rd attempt had gone wrong it would've been the end of the company.

As far as nuclear propulsion, I think public opinion would put a damper on that, and I'm sure all the private space people know that.



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23 May 2012, 4:40 pm

The answer to your question is simple.

The reason private companies are not racing with each other to produce the next big thing in rock propulsion is that there is no market for it.

Its a gigantically capital intensive thing to do R+D on, but there is no forseeable way to make a profit on it.


Next question.

Not saying that it will be that way forever.
In 2050 a million people might be living beyong on earth as asteroid miners, and there might be interplanetary cruise ships and tourism.

At that point there might well be a market of building better rocket engines that would power private r+d.



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23 May 2012, 4:49 pm

naturalplastic wrote:
Not saying that it will be that way forever.
In 2050 a million people might be living beyong on earth as asteroid miners, and there might be interplanetary cruise ships and tourism.

2050? I'm thinking 2150 or 2200 at the rate we're going.


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23 May 2012, 7:04 pm

Robdemanc wrote:
I think this is all BS. In space there would be no electomagnetic field to prevent the harmful particles from the sun. The passengers could come back with cancer and sue the private space flight companies.



Welllllll, there are OTHER ways to shield spacecraft solar radiation. And none of these spaceflights are well within the Earths magnetosheath so solar wind isn't an issue.



23 May 2012, 7:07 pm

Vigilans wrote:
Private companies are taking the burden from NASA so they can focus on better technology for further missions. The VASIMIR engine however does represent a good avenue for the future of long distance space flight.


It does not produce enough thrust to launch into orbit unless it is powered by nuclear engines. Nuclear power is pretty much the only known source of energy large enough to carry sizable spacecrafts fast enough for long distance space flight.


The Russian government, as it turns out, is already doing R&D on nuclear propulsion.



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23 May 2012, 8:28 pm

Russia has experience with space based nuclear reactors and a few years ago floated the idea of buildilng one that could power a VASIMR or other thruster for a Mars mission. The NASA administrator in turn made some remarks that sounded amenable to cooperation on something like that but it didnt really go anywhere.

The Russians are big on space rhetoric but tight with the money and the US isnt spending any money on that currently either. So it's not going anywhere in any current planning. If VASIMR is succesfully tested as an ISS thruster then maybe the subject will crop up again.



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23 May 2012, 9:13 pm

AspieRogue wrote:
Vigilans wrote:
Private companies are taking the burden from NASA so they can focus on better technology for further missions. The VASIMIR engine however does represent a good avenue for the future of long distance space flight.


It does not produce enough thrust to launch into orbit unless it is powered by nuclear engines. Nuclear power is pretty much the only known source of energy large enough to carry sizable spacecrafts fast enough for long distance space flight.


The Russian government, as it turns out, is already doing R&D on nuclear propulsion.


VASIMIR is only good for space, yes. However nuclear engines may not be necessary, there are many spaceplane concepts that could make access to LEO quite easy, and from there, to a space station with a deep space capable craft. I am for use of nuclear energy in space but for launches from Earth's surface I think it presents an unnecessary risk


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