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Rocket refueling stations and new kinds of engines for deep-space travel are high up on NASA's wish list for new technologies. So is a heavy-lift launch vehicle, which happens on Congress' wish list as well. But exactly what kind of next-generation rocket will NASA get? As far as Bobby Braun is concerned, the answer to that question is best left to engineers rather than lawmakers.
Braun, who is the space agency's chief technologist, discussed heavy-lifters and more today in a teleconference conducted during his visit to NASA Ames Research Center in California's Silicon Valley. Braun's main task is to get NASA's high-tech mojo working again, decades after the space agency made Tang, Teflon and Velcro famous.
NASA didn't actually invent Velcro fasteners, Teflon coating or Tang powdered drink mix - instead, it took those commercial innovations and adapted them for high-profile applications in outer space. Those applications, in turn, heightened public awareness and acceptance of new technologies. Something similar could happen again if NASA pushes through a new burst of technological innovation.
Today, NASA does spaceflight using a space transportation system that's been updated through the years, but really isn't dramatically different from what it was nearly 30 years ago. With the impending retirement of the space shuttle fleet, Braun and his fellow technology planners at NASA have an opportunity to do things in a radically different fashion.
During today's telecon, Braun said the new NASA will be spreading out its technological bets a lot more. "If we're going after grand challenges, which we are in the space technology program. ... For us to do that, we're going to have to take a little bit of risk," he said.
That means taking a risk-balancing "portfolio approach" to high-tech development. Some of the technologies NASA is betting on will result in new, even revolutionary, solutions to space challenges. "But frankly, we have to admit up front that some will not, and that has to be OK," he said.
The latest NASA-backed Centennial Challenge competitions, announced last month, focus on the kinds of technologies the space agency is looking for. The Nano-Satellite Launch Challenge, for instance, would award $2 million to folks who can demonstrate new ways to launch small satellites into orbit quickly and reliably. "Small sat is an important part of space technology," Braun said. "We actually called it out as a separate program, because in the formulation of space technology, I was worried, frankly, that if we didn't ... it would get lost in the larger technology pieces."
Other prize programs are aimed at producing more efficient solar-powered rovers as well as interplanetary robots capable of collecting soil samples without human intervention. Such technologies would be needed for more ambitious Mars missions ... and would surely be put to good use on Earth as well.
Braun's office is also reviving the NASA Institute for Advanced Concepts, or NIAC, under a new name (NASA Innovative Advanced Concepts). He said NASA is refocusing the program on research that could produce real-world technologies in less than a 40-year time frame.
"One of the problems that NIAC had previously, because it was so revolutionary, is that there were no technology programs to carry on that NIAC innovator's idea," he said. "There was no place for that idea to go."
Finally, there's human spaceflight: Although Braun isn't in charge of how astronauts get into space and back, he said he serves as NASA Administrator Charles Bolden's "primary advocate" for technology matters throughout NASA. And he has some definite ideas about how spaceflight technology should be done:
• Rocket refueling in orbit: Last year's review by an independent panel highlighted on-orbit fuel depots as a new approach for facilitating trips beyond Earth orbit, and it sounds as if Braun is totally on board with the idea. "When we send a human mission to Mars one day, we already know that about 80 percent of the mass in low Earth orbit for that mission is propellant," he told me. "So if we had technologies for propellant transfer and storage, you can imagine a lot of ways to get that propellant to low Earth orbit. Maybe it goes on one heavy-lift launch. Maybe it goes on many smaller-vehicle launches and is stored and transferred about in low-Earth orbit for the ultimate vehicle."
• New in-space propulsion systems: Braun noted that rocketeers have been talking about a wide range of architectures for future spaceships, ranging from shuttle-derived launch systems to kerosene-fueled approaches to experimental plasma propulsion systems such as VASIMR. Heck, you could even talk about solar sails or ion drives. "We need an in-space propulsion system, and you could imagine a number of advanced technologies, whether they be low-thrust or medium-thrust or high-thrust systems, to enable us to travel out beyond low Earth orbit. Now, the more efficient those systems are, the less mass we need to lift on the heavy-lift vehicle."
• In-situ resource utilization: "When we get to our destinations," Braun told me, "are we going to bring everything with us to an asteroid or to Mars? Or are we going to use the resources available on those bodies ... perhaps for consumables like life support, perhaps for propellant for the return journey home. Perhaps for materials, to manufacture a variety of devices at these destinations. Answers to these technology questions inform our beyond-low-Earth-orbit exploration architecture ... and greatly impact the requirements for the heavy-lift vehicle."
• Heavy-lift launch vehicles: That leads up to the multibillion-dollar question ... what kind of heavy-lifter should be designed and built? Legislation now making its way through Congress would provide NASA with an answer: Build a new rocket capable of putting 70 to 100 metric tons of payload into orbit by 2016. That's more than twice the weight of the space shuttle's biggest payload, but significantly less than the capacity of the Saturn 5 moon rocket.
Braun indicated that he didn't care for the idea of setting a legislative requirement for future rockets, because so much was dependent upon the other elements of a next-generation space transportation system:
"NASA is filled with technically strong people who could study the heavy-lift problem and relatively quickly determine the way forward. The agency is in the middle of doing that. In fact, we had a heavy-lift and propulsion technology broad agency announcement that was released by the Exploration Systems Mission Directorate. We're in the process of reviewing the industry inputs to inform our decision process. To make the most efficient and best use of taxpayer dollars ... I think that's NASA's job to think about these things, and to make the proper technical decisions on the proper time scale."
When it comes to revolutionary propulsion technologies, Braun said "there are some approaches out there that appear to show some promise." He declined to provide details, however, because NASA is in the midst of a competitive industry cycle.
"On top of that, I would like to look at it from a systems perspective," he said. "It's not all about the rocket. It's about getting beyond low Earth orbit."
Will Braun and NASA get it done? And on what time frame? A lot of questions about that will be hanging in the air over the weeks and months (and years?) to come ... but you don't have to wait until 2016. Feel free to weigh in with your own suggestions and observations in the comment space below.
Update for 9:25 p.m. ET: The San Jose Mercury News mentions a couple of technology programs that NASA Ames Research Center will be working on: a spacecraft that can fly off a runway like an aircraft and carry up to 20 metric tons (44,000 pounds) into orbit, and an inflatable system that can shield spacecraft from the intense heat of atmospheric re-entry.
There's also a project to be conducted jointly with the Pentagon's Defense Advanced Research Projects Agency, looking into beam-powered space propulsion. That follows up on NASA's Power Beaming Challenge, which paid out $900,000 to the Seattle-based LaserMotive team during last year's Space Elevator Games.
We may hear more about beamed power systems at the 2010 Space Elevator Conference, which takes place this week on the Microsoft campus in Redmond, Wash., just down the street from my msnbc.com newsroom. Stay tuned ...
Join the Cosmic Log corps by signing up as my Facebook friend or hooking up on Twitter. And if you really want to be friendly, ask me about "The Case for Pluto."
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Why build a new heavy lift rocket which will be less capable than a Saturn V, will need to be designed, built from scratch, and tested, when we already know how to build a Saturn V? This isn't even a case of "Not Invented Here"!
Not built from scratch, Shuttle-Derived. See DIRECT Jupiter class rockets...
btw, lower payload does not necessarily equate "less capable". The Saturn V was built for one thing, getting to the moon, at any cost (NASA has 10x the budget back then). DIRECT allows for a flexible path, in a cost effective manner.
gaetanomarano - stop repeating news media propaganda. That same line about "lost Saturn V blueprints" was picked up years ago by the media and has been repeated ad nauseum ever since.
NASA could absolutely build a new Saturn V if they wanted to - they have two complete Saturn V's sitting in museums at the moment that could easily be used for blueprints.
@gaetanomarano
First "they can't because they've LOST the SaturnV blueprints" then "yes, the can build it"
Make up your mind - which one is it?
Gaetanomarano, your "DIRECT Design Flaws" web page seems to be obsolete. DIRECT v3.0 utilizes the Shuttle Main Engines rather than man-rated RS-68's.
There is entirely too much arm waving, conspiracy theory, and conjecture (not to mention multi-colored highlight and font, etc.) to take that article seriously. I greatly appreciate your passion for the American space program, but can we keep the debate FACTS based, and maybe work on keeping the blogs concise and legible while we're at it?
Just my 2 cents.
CJSKS is correct. The colorful web pages are really over the top. I don't think the highlighting helps anything.
so it's just risk assessment now is it? it's all about money to you gaetanomarano?? Well, I realize the usefulness of an unmanned mission to NEOs. I realize money is an issue at getting missions off the ground.
But just because it's risky, complex, and expensive doesn't mean we shouldn't send humans to asteroids. In fact if we do send people to asteroids the science get's less complex after a successful mission, technology is less expensive, and the risks are better known and thus less risky.
Okay, I'll play along. WHY do they need a "fresh redesign"?
so it IS just about money to you. sad.
I'd suggest doing both. Create this army of robots you speak of AND send humans to an asteroid. the fact of the matter is many asteroids have significant amounts of raw material we could use. we'll make a fortune off of mining asteroids. there's your damn money.
you are clearly thinking of a manned mission to an asteroid as a "sample return mission". one we could easily do with robots. well, gaetano morano, I suppose you are right. but if that's the case then all the manned missions to the moon were simply sample return mission with no real value in having gone there with people.
Do you really not see what I'm getting at? we NEED human space flight, regardless of complexity, cost, or risk. It's not about money, or resources. It's about accomplishing monumental tasks because we can. If you don't understand that why do you spend so much time talking about your wishy-washy SLV?
oK, so maybe it's not all about money to you. I never said anything about mining asteroids being cheaper. But you could, perhaps, mine things that could NOT be mined on Earth due to the limited quantities.
and ONE huge reason to have NASA do the mining is so that and profits that are made off the resources mined would go to the government. that way tax payer dollars could (theoretically) be used to mine resources that could then be sold for profit (to the corporations).
corporations have too much power and money as it is.
you say "manned NEO's "sample return" mission can't be followed by a manned NEO's exploration and (later) by a manned NEO's colonization" because "they're just big rocks" well, some of those big rocks are big enough to do all those things. there are asteroids 60 miles in diameter. If a team could attach a ship to an asteroid by some (complex) means then they could explore it, and colonize it.
don't speak in Can's and Can'ts. ANYTHING can be done.
Let's take Eros for an easy example. "Eros is a goldmine in space, as well as a platinum mine, a zinc mine and many more minerals.." - http://news.bbc.co.uk/2/hi/science/nature/401227.stm
true, we could mine those things here on Earth at less cost, but at least we wouldn't have to worry about environmentalists. ;-P
all the things that we now mine from the Earth's crust, and that are essential for our economic and technological development, came originally from the rain of asteroids that hit the Earth after the crust cooled.
One could do many things on an asteroid. simply catching a ride around the sun would be beneficial. we could observe the solar system first hand from an asteroid. we could take along an observation telescope and see the solar system from the vantage point of an asteroid.
and we could colonize asteroids just for colonization sake.
you think of a reason. if you can.
Space ships that get us into orbit and the ones that get us from place to place in space have different requirements. HEAVY lift to Earth orbit then speed to our destination. The mission will dictate what we need when we get there. We need the capbility to assemble, maintain and fuel our space craft in orbit. This is the only way we can constuct a craft that can be used to carry enough support systems for a manned journey to anywhere except our own moon. Unless we as a planet can find enough cooperation to get this done it cannot be done. The cost is too high and resources to little for one nation to accomplish. Even a nation a great as the USA. We have taken the"One small step for man" last century. The giant leap will take all the resources and creativity of all mankind working together. THis is why it has not yet been accomplished. I for one feel this is something I am now become to old to see(I am in my mid 50's). Maybe one day my son will.
I would like to see another space station placed in the orbit between Earth and Mars. It could be the refueling point between the two planets.
Let's get this Star Trek thing going already. I'm not going to live forever, you know.
I share your sentiment here. We would all love to see some real human spaceflight. and the idea of multiple stations along the route to the outer solar system is a great idea if implemented correctly. and "correctly" just means we need to make these space station flexible to meet mission criteria.
I would love to see a space station between the Earth and Mars but I think the first space station we need to focus on is a Moon Base. we can shoot mission after mission to the moon. build a stockpile of things like propellant and space ship parts and stuff like that. build a space ship factory as part of the moon base. launch missions from the moon. Use Earth-to-Moon as the incremental steps and "Moon-beyond" as a venue for the "ultimate mission" to Mars or the asteroids or the Jovian moons.
"NASA is in the midst of a competitive industry cycle"....I am stunned, don't know exactly what that means..in the practical sense anyways. I am trying to reconcile industrial cycles at nasa and who is implicated as competitors....perhaps my bias has me looking for something that is not there. I think there is enough of sat 5's plans on the net to reconstruct it, whether or not we need help from india is not at issue. Rather the issue is primarily wrapped up in the nozzle. One for 14.5 psi atmospheric conditions and another for nearly zero psi atmospheric pressure. The spike nozzle and a few other creative designs tend to make for a multi-talented rocket engine, in fact I wonder if the issue is even touched upon by plasma/ion engines since they are of little use inside the gravity well (at this time). The paradox of which nozzle when and where appears to dictate the optimum fuel selection as well. My point is, the refueling depot may need more than one sort of chemical hoarde, thus a well planned depot may very well require several different storage mediums. I for one favor dual use scenarios, and on that note I wonder if any of the proposed designs even suggest the capability of collecting raw materials in space, such as hydrogen, perhaps even carbon and perhaps even more unlikely nitrogen, (he,Li,Ka etc..?) and using solar or thermal differential power to assemble chemical rocket fuels in situ ad hoc. Jeesh, wonder if they would allow me to compete with the big dogs for an orbiting refueling depot contract.....or did I leave my congressesional campaign donations only checkbook back at the office. Darnit.
Collecting the raw materials in space to fuel future spaceships is a big deal at NASA. I suspect we don't hear much about it because it's still an idea on almost everyone's napkins. I know there is speculation out there about using the abundant H3 on the moon as fuel.
Helium 3 could be used as a safer fuel in nuclear reactors. If we could build and launch a ship from the moon that was nuclear powered we'd be in like Flynn, so to speak. as long as that space ship never came to earth we would have to worry about any nuclear explosion in the upper atmosphere which is clearly something we should avoid at all costs.
For an excellent article about mining the moon of it's H3 go here - http://www.eastfieldnews.com/2.6688/mining-the-moon-1.974765
There is no truth at this site. the first words are "I think" and then it goes on and on and on about gaetano marano's opinions.
No. that's still not true. but that page you put up as "Truth" is a bunch of opinion. I realize Helium 3 fusion isn't doable today but the science is sound. there is clear evidence that the moon should have larger quantities of He3 than here on Earth. I don't want you to say anything to try to make me happy, I just enjoy a frank discussion of all known facts and theories.
I enjoy reading your pages G.M. "ghostnasa.com" is pretty interesting reading.
http://www.ghostnasa.com/posts/013asteroids.html
If you are using a language translator program it isn't working. otherwise you're English just isn't that great.
Anyhow, my point is simply that we shouldn't rule out a manned mission to an asteroid because of the cost, or the risks, or the complexity.
You talk about what a robot can do on an asteroid. the length of time it would take to completely explore an asteroid to 100% (by either a robot or a human) would be ridiculously long. Landing human beings on any extraterrestrial body is priceless!!
truthfully why are we concidering building a heavy lift launch vehicle capable of going strait to mars? Really the ISS should get a construction docking ring( or in orbit neat it) and construction of a vehicle capable of going to the moon and back and mars and back should be constructed in space where nuclear propulsion and anti-matter drives can be built, tested, and used. Rocket motors get the job done, but so did steam engines back in the day too...
HERE HERE!!
construction of space ships in space. it's going to have to happen sometime. (I mean really, haven't you guys seen the Star Trek movies? Every "Enterprise" was built in space.) ;-P
but seriously, We NEED to begin building things in space in earnest. the ISS was a great testbed for this, but now we need to be able to build an ISS in one year instead of ten and it should have propulsion systems next time.
Build the Saturn-V again? I would hope that we can do better than that by this time. It is a shame that we have built a pretty toy called the International Space Station. What we need is an orbital outpost aimed at exploring further out into our Solar System. We did not need to waste billions on some politician's idea of a Space Station. I can tell you where to get the money for an uprated space program. Stop pouring BILLIONS into two "pest holes" in the Middle East. Does ANYONE feel more secure after what we have done in Iraq and Afghanistan? We have made some very crazy people even more mad at us. It is an Arab problem and there are some VERY rich folks in the Middle East. What is wrong with leaving those problems to them? The majority of Americans want us out of there anyway. So, pull out and start spending (at least part of) those billions on our efforts in space. If you take a long-term view, which is more important? Throwing away money in the Middle East or moving into our real future which should include exploration of our Solar System (and beyond). When people in the future look back on this age in which we now live, they are going to wonder how we could have been so stupid as to waste our efforts on things that politicians are now telling us are important. Congress needs a good shaking up!
I don't know about you, but I am way tired of hearing the phrase "way forward".
Not nearly as tired as I am of 'winning hearts and minds.' Could be worse.
Make no mistake, God bless America. Yes, we can.
When Apollo went to the moon we sent everything up on one huge Saturn V rocket. As a result everything was limited in size. Imagine instead three launches (or maybe more), one carries the transfer stage to get you to and from the moon, one carries the lander and one carries the crew. Once in earth orbit they mate up and then fly to the moon. Put all the wieght of the HLV capability into a lunar lander how many crew could you land and how long could they stay?
Mars mission using similar approach would send the mission to Mars in pieces, send the lander seperate from the crew, send the return stage seperate from the crew, send food, air, etc seperate from the crew. More smaller transfer vehicles, more smaller launches from earth, etc. Make sure your critical systems get to Mars before you send the crew so if something goes wrong you don't loose the crew due to lack of air or water. The transfer stage that gets you to Mars stays at Mars so it is smaller and requries less fuel to get the crew home.
Kind of like the whole Apollo mission, we built a huge rocket to get the transfer vehicle, LEM and crew module into orbit. The transfer vehicle get them to the moon and the LEM takes them down to the surface. Only the part of the LEM carrying the crew returns to orbit so less fuel is needed to get off the moon. Ultimately only the crew module lands back on earth so out of that huge Saturn V rocket only about 1% of the original mass returned to the surface of the planet (at least intact).
This is exactly the idea that I think NASA will end up using regardless of everything else (unless they figure out some antigravity lift system). Retired NAVY senior chief, we need more guys like you on Obama's (and future presidents) science advisory team.
OK, the nuclear powered rocket out in Nevada, it worked 50 years ago, and almost was brought back in 2002, why not bring it back on the table?
Nuclear contamination of the uppermost atmosphere spells catastrophe. But other than that it's a fine idea. I'd like to see nuclear space craft built on the moon and their reactors fueled with Helium 3 (mined off the moon's surface).
Joe... did you forget to take your meds again??
Why not set a 7 to 10 year timetable for upgrading the Apollo technology system for a return to the moon by 2020. I just don't understand the logic in throwing money at a heavy lift system that will have half the capability of the Saturn 5. The unwillingness to transform Apolo raises question about the legitimcy of the mid-2oth century program.
One more time, High altitude balloon launching of small multistage chemical rockets would allow nanosats to LEO. Hydrogen lifting gas is inexpensive and could be used over ocean launch areas. Balloons in the past have gone higher than most of the atmosphere and could save much of the energy fighting drag. Then a low angle thrust could put some water(ice) into orbit and solar power could turn that into fuel.
Based on the insurmountable problems of keeping the human in the loop, I believe we should being trying to define the next phase of "deep space exploration" with the smallest possible payloads. That includes application of nanotechnology to design the smallest possible machines "to do the job".
If we are to have any success in space exploration (real exploration instead of blasting off bigger and bigger firecrackers with that poor hopeless human strapped, hangcuffed, to the seat) we need to remove the human from the loop, from the specifications ( from that software monster that was created for Space Station Freedom) and eventually from the new designs.
I truely believe that the present documentation is soley structured around the manned requirements and unless we do a proper "cut and paste" job of removing the manned requirements we will never be able to configure a doable system to go any where.
Oh no. We need manned spaceflight. it's just that simple. I think we also NEED the robot element to aide Humankind in it's spaceflight endeavor. Send probes to Mars. Send return missions to Mars. we already have robots there, but hey let's send more. why not?
I say send everything we can to everywhere we can. As human beings we should stop fighting eachother and start working together to explore the universe.
Imagine a world in which everyone has a job. Public works projects are great at putting people to work and creating a world people can look at and be proud of (just look at the Tennessee Valley Authority).
We could build the infrastructure of an international federation of space program employees all working together to build everything the space program needs. Every line of work will be need in this endeavor. Everyone would have an opportunity. Everyone would have purpose.
RE: "gaetanomarano", big blank spaces make no argument and even less impact
The 11th Congress is shortsighted in not funding commercial and tech as requested by President Obama. If Congress were truly concerned about American access to space they would persue a human rated Atlas V or Delata IV (and ultimately the 100 ton Delta being theorized) as soon as possible.
All this tech-dev will take more than a $19B a year budget. As Congress looks for ways to motivate this economy I can think of no better way than investing in America's competitive edge. No better way in conserving America's place in the place world, no better way to invest in American security, now and for the rest of this decade and even farther beyond.
NASA's missions require a 2011 Budget of $21B,
let your Congress-people know!
Thomas Rudder has the exact right idea. but I would suggest a 100 billion dollar budget. It sounds ludicrous I know, but I feel NASA should be hiring instead of making layoffs. And America should be Putting missions into space on a monthly basis.
I asked a NASA retiring employee why the center fuel tank for the shuttle was not designed to be placed in LaGrange orbit with the Moon and Mars. His reply,"We talked about it but it did not employ enough people. (He worked for a Sub)."
Exactly, the NASA emperors need to propose large pipe dream projects in order to maintain their empire (increase their annual budget or keep it from reducing at a minimum). This has been the problem at NASA since the Apollo program. Using the favourable public acceptance of the moon missons the NASA emperors (Level 1, 2, and 3 managers) decided to continue proposing larger and larger programs to bring the annual budget (space community personnel) to a point where the elected politicians (controlling the budget) will find it hard to reverse because of potential public out cry.
These are the cheap shots NASA managers have been doing to the elected officals. Time for a real change at NASA Mr Obama.
NASA Emperors? NASA does almost a complete overhaul every time the wind blows. What empire? What are you smoking? I think you need to look at the elected politicians as the empire. How many of them were in office when the Bush was in office...now let's look at NASA....how many of them have the same position? Most of the leaders during Bush's office are not working for NASA anymore.
We are just about a fully hopeless nation when it comes to deciding on a direction for our future space goals. Thank god our fathers and mothers provided us children with such a solid foundation so as our country rusts away it will happen slower rather then faster.
If you folks believe in optimism then I wish to suggest that the only assured reliable access to space on an American built vehicle (once the Shuttle is in the museums) will be flying on top of an United Launch Alliance Delta IV rocket. Just forget about NASA ever building and flying a larger cargo vehicle in our generation since there just is no money to pay for it! That mean zilch monies? Zero! Nada! NONE!
So please forget about President Obama making such funding happen because he is also due for a layoff in January of 2013.
May I suggest that if we do not make use and expand upon our nation's currently flying and ultra reliable launch vehicles then we will not be paving the way to deep space such as a journey to Mars in the next 30 years, but rather other nations of the world will lead the path forward. Believe it that other nations of the world actually have balanced budgets and loads of funding, and solid command for direction.... My best guess is the Chinese. Anybody have other suggestions.
But in my opinion as a 55 year old that has lives through a lot of change, I do honestly believe that I will receive just about as much satisfaction seeing any human of this earth land on another world. Americans will see this journey on their TVs, but optimistically speaking, we can forget about American’s wearing the space shoes that make first contact with the Mars soil. Our leadership has failed us!!!
I think the secret to the future of space travel is a combination of hybrid air ship and plasma rocket.
You could build a high altitude airship that could also handle space conditions. Once it reached a high enough
altitude you could then fire the plasma rockets reach earth orbit.
I was not alive during the Apollo days but I think they had a the right idea. The media was positive and Americans were supportive of NASA. Most Americans don't have any idea when a shuttle has been launched or even if humans have been to Mars or not. Education is important and the media has taken it's focus off the positive focus of NASA and has decided to focus on the negative coverage of NASA. Congress needs to support NASA instead of putting handcuffs on them with what little budget they are willing to give to NASA. BTW..it was Bush and Bush's congress that decided to stop launching the shuttle, not the current one. We need to let our representives know that we want them to support what our NASA leaders are asking for (they just don't pull numbers out of a hat). Current Representives seemed to be only worried about being re-elected, not the good of the future of America.
Poor old Gaetano Moron-o. All these wild theories and self-serving statements, with nothing to back them up. Perhaps Mr. Boyle should take a page from several other spaceflight-related forums, and ban Gaetano. He's far more disruptive than he is entertaining...
mob_barley, Solid-core nuclear thermal rockets can start from LEO, if you wish, and probably will. All the manufacturing infrastructure for them is down here, not on the Moon.
And these are fission reactors that impart their heat to a liquid hydrogen reaction mass, and having tested a number of them under the Rover and NERVA programs, we know this works, and that they can be small and light enough to do the job. (Their thrust-to-weight ratio was less than one, but that's also okay when you're starting from LEO, their specific impulse is still at least twice that of hydrogen/oxygen chemical rockets)
No one yet knows how to make a fusion reactor that produces net power, and Tokomak-like devices are likely to have T/W ratios much less than one. Massive engine, pitiful thrust.
The proposals of various kinds that involve high temperature 'fissioning' of a boron-11 nucleus hold great promise, but I would not count on those until they also demonstrate net power production.
(But if it works, boron is plentiful on both Earth and the Moon...)
The reason few are aware when a shuttle launches is that the missions seldom accomplish anything of value. The purpose for putting men in space apparently is.... to study men in space so we can.... put men in space.
What's the hurry? Space will still be there in 2050, 2100, and so on. Unmanned missions are clearly the way to go at this time.
"I was not alive during the Apollo days but I think they had a the right idea. The media was positive and Americans were supportive of NASA. Most Americans don't have any idea when a shuttle has been launched or even if humans have been to Mars or not."
I was around for that. Trust me, the public's attention span was plenty short back then, Had it not been for 'the problem,' little attention would've been paid to Apollo 13. (They did a televised tour of the interior of the spacecraft that was never actually carried by the networks.)
And we should not be terribly surprised. Crowds don't gather in Paris when a non-stop transatlantic flight comes in...at some point, human space flight to any particular place should be regarded as a common occurrence.
But there nevertheless are people who want to be pilots, or otherwise work in aviation. Flight, like the sea, will always have an element of 'romance' for some, space will be the same.
That's why we should never count on 'inspiration' as justification for humans in space. Those like us who already tend to care, still will. Those who don't....merely get used to it. We got used to LEO (and I also remember full, all three orbit network coverage of John Glenn's flight) and even some space enthusiasts whine about 'been there, done that.' we'll get used to the Moon and Mars, too.
And that's okay, as long as it becomes common and economical enough that we can get used to it. (something that really hasn't even happened with LEO yet, despite appearances...)
The next-generation space propulsion system, a new kind of electrodynamic thruster, is coming up.
http://www.youtube.com/watch?v=9ScAHXN_kAY
I'm excited about the new NIAC. It's great to see NASA working more seriously towards innovative, risky technology development. That's the proper role for a government agency — blaze the trail, then let industry take over and make the breakthroughs routine.