NASA's Next 50 Years

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BSPhysics
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NASA's Next 50 Years

Post by BSPhysics »

Any thoughts from the forum?

Here's an article at space.com highlighting their opinion and a quote in reference to the year 2058...

"Construction has begun on a radio telescope on the moon's far side and the lunar base has been established for years as one of the nation's centers for excellence in fusion and alternative energy research."

http://www.space.com/news/081001-nasa50-road-ahead.html


BS

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Re: NASA's Next 50 Years

Post by MSimon »

BSPhysics wrote:Any thoughts from the forum?

Here's an article at space.com highlighting their opinion and a quote in reference to the year 2058...

"Construction has begun on a radio telescope on the moon's far side and the lunar base has been established for years as one of the nation's centers for excellence in fusion and alternative energy research."

http://www.space.com/news/081001-nasa50-road-ahead.html


BS
I see no point of making the moon a fusion research center except for access to He3. Which could more easily be brought back to Earth, IMO.
Engineering is the art of making what you want from what you can get at a profit.

BSPhysics
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Post by BSPhysics »

Exactly! I posted that quote in order to show the contrast between mainstream media, even science media, the public and the realities of fusion. I have an extremely social job so I spend a lot of time with the regular folks. John Q. Public are completely unaware of not only IEC fusion and the interesting history of the last few years but they cannot comprehend the enormous possiblities. College educated adults don't even buy it; the disconnect is far reaching. So much so that predictions of the future like the one in the article can be way off base. Even if Dr. Nebel is completely succesful, the communicators of the technology to the media have their hands full. The politics will be worse.

What is NASA's immediate future in a BFR world? What happens to ESAS? What happens to the shuttle/Ares workforce in all of those congressional voting districts?

BS

djolds1
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Post by djolds1 »

BSPhysics wrote:John Q. Public are completely unaware of not only IEC fusion and the interesting history of the last few years but they cannot comprehend the enormous possiblities.
Sci fi fans should grasp the possibilities in about 0.32 seconds. :D
BSPhysics wrote:College educated adults don't even buy it; the disconnect is far reaching.
There have been too many disappointments. We were supposed to have Clavius Moon Base by 1990, and instead the world basically gave up on manned space beyond LEO, and mass scale manned space of any sort. The cheap costs and frequent access NASA advertised in the '70s were purest crap. The "promising next generation" methods like scamjets (NOT sp) never materialized. Once the prestige and "debt to a martyr" of Moon landings was achieved, the politicians no longer cared about space. The word for Joe Average's attitude is "jaded." :(
BSPhysics wrote:So much so that predictions of the future like the one in the article can be way off base. Even if Dr. Nebel is completely succesful, the communicators of the technology to the media have their hands full. The politics will be worse.
Depends on how others grab on. If QED rockets are expensive and no other national or private players pursue them whole hog, the next 50 years will be like the last 50. A few national prestige missions and otherwise zilch. If say China or another well funded aspirant (India, Brasil?) starts a space race, the US and others will ramp up quickly just so that the enthusiast doesn't own the solar system.
BSPhysics wrote:What is NASA's immediate future in a BFR world? What happens to ESAS? What happens to the shuttle/Ares workforce in all of those congressional voting districts?
Assuming Bussards work and a competitor, national or private, makes them the only game in town, NASA is basically finished. It becomes the National Aerospace Laboratory. New agencies are created or spun off NASA to take over regulation of space flight, and purchases distribute across multiple gov't agencies and private ventures.

As to the pork, possible that political pressure is applied to strangle the new ventures like SpaceX and keep construction limited to the pork-laden legacy Aerospace Corporations. In which case space access is more expensive than need be, but not as horrendous as it is today. The parallel would be Boeing heavies as the only aircraft, with Rutan small-built Learjets banned.

Duane
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choff
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Post by choff »

Back in the 70's, after the last moon mission, I wished they would have sent the last 3 Saturn V missions as additions to Skylab. NASA sent 1 Skylab, 2 return trips to Skylab, and a PR linkup with the Russians with the last 4. If they had just sent the last 4 up and linked them together, they would have had a 200 ton space station. Instead of building the Shuttle they could have built something on the scale of the Gemini and used it as the supply vehicle. A little basic planning would have put them 3 decades ahead.
CHoff

Skipjack
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Post by Skipjack »

I think they should have overlooked the political implications and used nuclear propulsion systems (NERVA or improved NERVA) for shuttles that go from LEO to lunar orbit (and later from LEO to mars). The biggest problem of course would still be getting into LEO. I would not mind using NERVA propulsion for this as well, but I think I am pretty much allone with that...

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Post by djolds1 »

choff wrote:Instead of building the Shuttle they could have built something on the scale of the Gemini and used it as the supply vehicle. A little basic planning would have put them 3 decades ahead.
The shuttle is one of those ideas that sounds wonderful even to the informed for the first 15 minutes, just like "horizontal takeoff airbreather" seems intuitively cheap and simple; except that they aren't. Great for sound bites though.
Skipjack wrote:I think they should have overlooked the political implications and used nuclear propulsion systems (NERVA or improved NERVA) for shuttles that go from LEO to lunar orbit (and later from LEO to mars). The biggest problem of course would still be getting into LEO. I would not mind using NERVA propulsion for this as well, but I think I am pretty much alone with that...
To do that you need to rewrite the social and political trends of 1960-1975. Redirect the inevitable social radicalism in the West, escalate the Cold War so that large military basing & weapons infrastructures are built in space. Once you pass a tipping point, staying there is self-justifying.

And the best solid core nuclear thermal rocket was DUMBO, t/w good enough to take off from the Earth.

Anyway, landing large cargoes on Mars is much harder then is usually admitted. :( Two tonnes is about the max possible for current landing methods, maybe scaling up to 10-20 tonnes for next generation methods, and the Great Ghoul of Space still eats 60% of the missions sent.

Duane
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BSPhysics
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Post by BSPhysics »

Duane, you are an optimist. I admire that :!: Please, prove my skepticism wrong. I'm afraid it will take a national emergency of some kind to get it all moving in the right direction without major political hurdles.

BS

Skipjack
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Post by Skipjack »

Yeah, one might use a light bulb principle gas core nuclear reactor for higher efficiency. I read some people were theorizing with this a while ago. I also assume that one could improve solid core reactor based NERVA propulsion systems even more more with todays tech. After all most of the testhardware was build in the 60ies (if memory serves me correctly) and since then only paper studies have been made, with very little actual effort being put into it.

Betruger
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Post by Betruger »

djolds wrote: Anyway, landing large cargoes on Mars is much harder then is usually admitted. :( Two tonnes is about the max possible for current landing methods, maybe scaling up to 10-20 tonnes for next generation methods, and the Great Ghoul of Space still eats 60% of the missions sent.

Duane
Duane,
Go to the space.com forums and search for a thread started by user 'Keermalec' titled something like 'Mars, 8 tons at a time'. He has crunched the essential numbers to make it work. There was another preceding thread that you might find technicaly interesting in the old uplink.space.com forums, too.

Here's one of those..

And if anyone with plasma physics knowledge ( :wink: ) has an hour or two of free time .. Check out this irresistible force vs. immovable object debate on the physics of the sun.. Skipping to the last few dozen pages and limiting yourself to the plasma circuits arguments could possibly be helpful in pulling the discussion out of its trenches.

drmike
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Post by drmike »

Weird. At least on this forum nobody is afraid to actually type in the math. Somebody needs to write LaTex to BBcode so we get mathicons instead of emoticons. Arguing about what the math means is more fun anyway.

djolds1
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Post by djolds1 »

Skipjack wrote:Yeah, one might use a light bulb principle gas core nuclear reactor for higher efficiency. I read some people were theorizing with this a while ago. I also assume that one could improve solid core reactor based NERVA propulsion systems even more more with todays tech. After all most of the testhardware was build in the 60ies (if memory serves me correctly) and since then only paper studies have been made, with very little actual effort being put into it.
The problem isn't efficiency, its thrust-to-weight ratios. You need a t:w better than 1 to get off this mudball. QED rockets powered by Bussards will do that. Chemical rockets do that now. But most of the nuclear rocket designs that can achieve that are ugly.

Absent working Bussards, a prestige megaproject would cut through that, eliminating the need for the t:w >1 stage of the flight.

Duane
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Skipjack
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Post by Skipjack »

Duane I am not entirely sure what you are referring to. Do you mean the higher weight of NERVA rocket engines?
They do weight more, but they do have a higher ISP as well. Less fuel means lower system weight.
I do not know what you mean with ugly. Most of the proposed rockets are big though thats true, but I for once never had a problem with big ;)
We will see about Bussard, it has to work first. It would be very welcome though if it did (would be a lot easier to get past that green folk out there than NERVAs ;) ).

djolds1
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Post by djolds1 »

Skipjack wrote:Duane I am not entirely sure what you are referring to. Do you mean the higher weight of NERVA rocket engines?
No. Thrust to weight ratios.

http://en.wikipedia.org/wiki/Thrust_to_weight_ratio
http://www.projectrho.com/rocket/rocket3c2.html

For a rocket engine to power a ship off the Earth, its thrust to weight ratio needs to be greater than 1.0. Less than that an it will not be able to get the ship off the Earth. The engine can still accelerate a ship in space, but is no good for liftoff.

NERVA has a t:w of <1.
DUMBO has a t:w of >1.

High thrust and high Isp are the holy grail of rockets, but at this point we can build only two designs that achieve that, and both are, umm, unpopular, shall we say.

Orion. Throw nuclear bombs out the back and catch the plasma with a shock absorber. Fallout for the fission model can actually be minuscule, but no one cares.

NSWR. Throw water laced with high concentrations of fissionable salts out the back. Creates a continuous, moving, low-level nuclear detonation that flashes the water to steam as reaction mass. However, the neighbors would not be amused, given that real estate values are low enough as is.
Skipjack wrote:They do weight more, but they do have a higher ISP as well. Less fuel means lower system weight.
Other forms of "conventional" nuclear rocket engines, such as gas cycle and liquid cycle engines, have better Isps than the solid core engines like NERVA. But the solid core engines have a t:w 2 to 4x better than the gas and liquid core engines.
Skipjack wrote:I do not know what you mean with ugly. Most of the proposed rockets are big though thats true, but I for once never had a problem with big ;)
Politically and medically unacceptable. They tend to spew fissionables out their rear ends. That is not popular when it happens on Earth.
Skipjack wrote:We will see about Bussard, it has to work first. It would be very welcome though if it did (would be a lot easier to get past that green folk out there than NERVAs ;) ).
Perhaps. I'm rightfully cynical about the Greens, who seem to have a BANANA attitude.

Duane
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Skipjack
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Post by Skipjack »

I do know what the thrust to weight ratio is, but I do not quite know where you get your information Duane.
According to Astronautix at least one of the various configurations that were designed and or tested had a Thrust to Weight ratio of 7.46.
http://www.astronautix.com/engines/nerva.htm

Further I would like to point out that the US was not the only country considering this kind of engine. The Soviets originally wanted to use simillar engines for their N1 heavy lift rocket.
http://www.astronautix.com/lvs/n1.htm

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