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Nuclear rockets would enable fast "point and shoot" missions to Mars -- 3 months outbound, 40 days on Mars, 4 months return; total mission time less than 9 months. Compared with using less powerful chemical rockets and planetary gravity assists, missions using nuclear rockets would involve lower crew radiation exposure, smaller supply and equipment requirements, and other advantages.

NuclearSpace.com has a really interesting article about a hypothetical design for a fully reusable, non-polluting nuclear rocket based on the Saturn V form factor, that could lift ONE THOUSAND TONS of payload into Earth orbit -- that's a whole space hotel in one shot -- and return with an equal size cargo to a soft landing.

The design is based on a "nuclear lightbulb" reactor, consisting of a bulb of synthetic quartz enclosing a cloud of gaseous uranium such as UF6. A lighter buffer gas swirling around the inside of the bulb confines and controls the shape of the uranium cloud, which heats up to 25000C (about 7 times the melting temp of any solid core reactor). The cloud emits intense ultraviolet light, which radiates through the quartz and is absorbed by hydrogen flowing past the outside of the bulb. The hydrogen is superheated (but not irradiated), and shoots out of the rocket nozzle to provide thrust. Because the uranium is completely sealed inside the bulb there is no contamination of the exhaust.

The massive payload carrying capacity of this type of rocket (roughly 30 times that of the space shuttle) would radically change the space travel equation by making weight concerns a thing of the past. We need this technology to move into the future, and we need NASA to brave the PR implications of the word "nuclear" and move ahead with it.

You mean these?

We still have the tech. It's come and gone as many different engines, including DUMBO, Timberwind, the Space Shuttle upper stage engines, and (most recently) TRITON.

The articles linked aren't specific about mission details, but NASA planners acknowledge that a major problem on any Mars mission will be radiation exposure. Getting to Mars and back at all with chemical rockets requires either taking a long slow trajectory or using gravity assist from other planets, making any Mars mission more than a year-long prospect and exposing the crew to radiation beyond the allowable lifetime limits. The shielding method that stands head and shoulders above others is plain water. A double hull spacecraft with about a foot thick layer of water between the hulls would cut radiation exposure by more than half -- far better than anything else proposed. The water hull would also provide micrometeorite shielding. The outer few inches would freeze. If a micrometeorite penetrated the hull, water leaking out through the hole would freeze re-seal it immediately. The water hull would also provide an enormous heat sink that would eliminate the need for a complex refrigeration system to get rid of heat from human bodies and equipment. But to haul that much water weight around is beyond the current capabilities of chemical rockets.

One possible solution is to use nuclear rockets to get there and back. For sheer power they leave chemical rockets in the dust. A nuclear powered rocket would enable "point and shoot" missions, essentially aiming at the spot in the sky where the destination will be in a few months, overcoming planetary gravity by brute force. Here's an interesting article about a design for a fully reusable, non-polluting nuclear rocket based on the Saturn V form factor, that could lift one thousand tons of payload into Earth orbit and return intact to a powered landing. No solid fuel boosters, no jettisoned fuel tanks. Just a big rocket that takes off and comes back.

BTW, Fun link of the day. Figured you might appreciate that one.

A more near-term possibility would be to use air-breathing stages or engines. A regular jet engine will only take you out of most of the atmosphere and impart minimal momentum, of course; to get that high delta-V orbital energy, a scramjet could get you 1/2 to 2/3 of the way.

I'm still not so keen on the scramjet engines. The engines themselves are fine, but the incredible stresses on the airframe are an engineer's nightmare. The airframe would have to be even more sturdy than the SR-71, which pulled some rather crazy tricks (such as leaking very expensive fuel to cool the skin) that just aren't feasible in a normal craft. If a scramjet was built like the SR-71, it would be too expensive to ever get off the ground!

If we could get a nuclear thermal engine demonstrated in-space for about a decade without any problems and without any fuel erosion, public resistance to surface launches will wane. I doubt that'll happen, though - current-gen nuclear power just isn't reliable enough.

I don't think that's as much of a problem as it seems. As I've stated before, Pratt & Whitney think they've got the problem licked. They're using Tungsten cladding instead of Graphite, which should actually provide better performance and less erosion. Get a few hundred hours on those engines (in space, of course) and we'll have a pretty good idea about whether atmosphere is feasible or not. It certainly can't be any worse than a plane that must withstand similar heat tolerances on the outside! ;-)

MPDT propulsion off the planet would be possible if we had an uber-low mass power source... now that would be nifty and very sci-fi like (lifting off the surface with engines that have a blue glow, not flames and steam, coming out of them) :)

Wouldn't that be great? I read a rather funny post the other day that went something like this:

"What we need to do is invent that glowey blue shit. Everytime you watch a space movie, there's a ship with glowey blue bits. On the Prometheus (Stargate) they get really bright when they start working. On the Enterprise they flash brightly just as the ship is about to go really fast. In all cases, they get around because of the glowey blue stuff. If we invented the glowey blue stuff, we'd already have been everywhere!"

Gave me a good chuckle. ;-)

We need to figure out how to get rid of the fallout though

Supposedly, they have. Pratt and Whitney only need a buyer before they start constructing the engines. The engine is a tri-mode jobbie that can do high Isp thrust in space, and low (for NTR) Isp afterburning for high thrust, atmospheric work. Once in space, the engine can idle to produce ship's power.

Nice engine, eh? I want one. ;-)

http://www.nuclearspace.com/a_liberty_ship.htm It is simple, no nuclear materials comes out of the exausts. All you do is super heat some material to rediculous levels and your done. Any activity has a negative impact, but then the biggest human contibutor to radioactivity in the atmosphear is burning coal. As for accidents, you need about 1000 accidents to release as much nuclear materails as those above ground attomic tests. Oh, and make them BIG ...

One thing this and most other articles fail to mention is that radiation exposure on the Martian surface is about 75% of that in space. The thin Martian atmosphere offers little protection, and when particles get through and strike atoms in the soil they create a scatter of secondary radiation, some of which scatters upward.

One of NASA's Design Reference Missions to Mars involves a total mission duration of 900 days with a 500 day stay on the surface. This mission would expose the crew to more than their allowable lifetime radiation dosage. Another mission profile involves a 435-day duration. Both of these missions involve a year's round trip travel time, and virtually doom the crew to early cancer deaths after their return to Earth.

Gaseous Core Nuclear Rockets would make Mars missions truly feasible. For reasons discussed in detail here, here and here, among other places, GCNR rockets would get a mission to Mars and back in 270 days, with 7 months travel time and 60 days on the surface. Additionally, the GCNR rocket would have huge carrying capacity, enough for the craft to carry a foot-thick water shield in a double hull. Such a ship would reduce the crew's total radiation exposure to about 1/5 of the 435-day mission and 1/10th of the 900 day mission. The water layer would also act as a giant passive heat sink, eliminating the need for a complex refrigeration system. It would also be a self-sealing micrometeorite shield -- the outer few inches of water would freeze, and if a micrometeorite punctured the hull the escaping water would refreeze over the hole immediately.

Yet another story about NASA "next generation" designs that are just reengineering old technology. NASA should bite the bullet and develop nuclear rockets. Experimentation in the 60s produced a crude solid-core reactor engine called NERVA, but it was heavy and underpowered, and would have released a lot of radioactive pollution. There are much more promising, non-polluting nuclear engine designs now that would outperform anything NASA has on the drawing board. One is called a Gaseous Core Nuclear Reactor, also known as a "nuclear lightbulb."

Basically it's a big quartz bulb containing a cloud of gaseous uranium such as UF6, confined to the center of the bulb by a buffer gas swirling around the inside. The UF6 heats up to 25000 C, about 7 times the melting temp of any solid core reactor. It emits intense ultraviolet, which passes through the quartz and is absorbed by slightly doped hydrogen flowing over the outside. The hydrogen heats and expands, exiting the nozzle to provide thrust. There is no actual combustion and no need to carry liquid oxygen. The nuclides confined within the bulb do not enter the exhaust stream, and the hydrogen exhaust itself is not radioactive.

Here is an article on NuclearSpace.com that describes a detailed design for a fully reusable GCNR rocket based on the Saturn V form factor, which would not only lift 1000 tons of payload into orbit but also return intact to a powered landing in the manner of the now defunct Delta Clipper.

GCNR rockets would not only be able to launch entire space hotels in one shot, their enormous lifting capacity would also make Mars missions practical. Proposed 2-year Mars missions using traditional planetary gravity assist trajectories would give the crew fatal radiation doses. A GCNR rocket could carry a fantastically equipped Mars mission with a foot-thick layer of water/ice shielding, on a point-and-shoot trajectory that takes three months each way. But that's another topic all its own.

Anything nuclear is going to create a big PR problem, but NASA is supposed to be all about public education as well as putting things into space. I had hoped for more guts from their new leadership. We've been mucking around in earth orbit for decades. It's time we built real spaceships that can handle really significant cargo.

You don't have to vent radioactive exhaust to get the benefits of nuclear energy for thrust. See here.

To do that, we need to go nuclear. No, not Orion - there are several designs that don't vent radioactive exhaust and you can even use them to get rid of nuclear waste.

Whenever I read one of these NASA "next generation" designs that are just reengineering old technology, I wonder when they are going to bite the bullet and go for nuclear rockets. Experimentation in the 60s produced a crude solid-core reactor engine called NERVA, but it was heavy and underpowered, and would have released a lot of radioactive pollution. There are much more promising designs now. One is called a Gaseous Core Nuclear Reactor, also known as a "nuclear lightbulb."

Basically it's a big quartz bulb containing gaseous uranium such as UF6, confined to the center of the bulb by a buffer gas swirling around the inside. The UF6 cloud heats up to 25000 C, about 7 times the melting temp of any solid core reactor. It emits intense ultraviolet, which passes through the quartz and is absorbed by slightly doped hydrogen flowing over the outside. The hydrogen heats and expands rather than combusting, exiting the nozzle to provide thrust. No need to carry liquid oxygen. The nuclides confined within the bulb do not enter the exhaust stream, and the hydrogen exhaust itself is not radioactive.

Here is a really interesting article that describes a detailed design for a fully reusable GCNR rocket based on the Saturn V form factor, able to lift 1000 tons of payload into orbit (ten times NASA's latest new design) and return intact to a powered landing in the manner of the now defunct Delta Clipper.

GCNR rockets would not only be able to launch entire space hotels in one shot, their enormous lifting capacity would also make Mars missions practical. Proposed 2-year Mars missions using traditional planetary gravity assist trajectories would give the crew fatal radiation doses. A GCNR rocket could carry a fantastically equipped Mars mission with a foot-thick layer of water/ice shielding, on a point-and-shoot trajectory that takes three months each way. But that's another topic all its own.

Sure, anything nuclear creates a big PR problem, but NASA is supposed to be all about public education as well as putting things into space. I had hoped for more guts from their new leadership.
We've been mucking around in earth orbit for decades. It's time we built real spaceships that can handle really significant cargo.

How's about this one? Why limit ourselves to "100 tons to orbit" when we can do a thousand tons?

Here you go.
http://www.nuclearspace.com/a_2009_Rover.htm

The antimatter must be one a hell of a job to handle safely. I don't see the future of antimatter fuel in a little light spaceships. Because of all the risks, only the large and heavy space vessels can be include all the necessary technology.

Time to slip in my usual plug for Gas Core Nuclear Reactor rockets. The basic design, sometimes referred to as a "nuclear light bulb," involves a bulb of pure synthetic quartz containing gaseous uranium hexafluoride which is compressed to criticality by a buffer gas swirled around it, which also prevents the UH6 from touching the inside of the bulb. The reaction gets so hot it radiates intensely in the ultraviolet, which passes 100% through the quartz. Hydrogen gas flowing over the outer surface of the bulb absorbs the UV, gets superheated, expands and shoots out through the rocket nozzle to provide thrust. The radioactive reactants are confined to the bulb so they do not contaminate the exhaust stream, and the hydrogen itself does not become radioactive.

Here's a fascinating article that describes a design for a non-polluting, 100% reusable GCNR rocket based on the Saturn-V form factor, capable of lifting one thousand tons of payload into orbit and returning the same size payload to a powered landing. That's enough lifting power to take up a whole space hotel in one go. A nuclear rocket could also power a point-and-shoot Mars mission that would take half as long as the contemplated gravity-assist strategies, and carry enough radiation shielding to make the trip actually survivable for the astronauts.

I was under the impression that the reason we don't currently have nuclear outfitted space technology (not counting decay powered satelites i.e voyager) was that if the Challenger/Columbia thing happens again it sprays the planet with refined nuclear material.

That impression is quite wrong. Nuclear technology has not been used because:

1. It hasn't met the mission profiles. (It was even considered for the Shuttle upper stages.)
2. People are afraid of nuclear.

In the case of CEV Spiral Two, the engines would be used for pure orbital work, so there would be little to no concern of any materials reaching Earth.

If anyone knows of a way to get thrust from fission I'd love to hear it.

Man, I thought I'd gotten everyone around here trained in how Nuclear Thermal Rockets work. Here's the short of it:

Most nuclear reactors derive their power production from the thermal aspect of the reaction. As the core heats up, the heat is pumped into a generator where a turbine is turned. During the push to reach the moon, some enterprising engineers figured that if you could heat a propellant using a nuclear reactor, you could dump as much thermal energy into a working fluid as the materials could withstand. The result is that massive amounts of thrust can be obtained by simply heating a stream of hydrogen, oxygen, or even plain old air. (See: Project Pluto; rather nasty weapon that was.) Since hydrogen and oxygen can't become radioactive, there would be little issue of spreading nuclear materials. Unfortunately, there was a Graphite Ablation problem from the heat, but the modern TRITON engine fixes that by utilizing Tungsten cladding.

Does that answer your question?

I love the Liberty Ship concept. Unfortunately, there's only one problem: Gas-Core Nuclear Rockets are as of yet unproven. Many engineers have their doubts that they will even work. (Although I think with enough money behind it, the concept can be made to work. ;-)) As a result, the GCNR proposal is a bad idea for early space access. It would be another miracle technology that may or may not pan out. It's a much better idea to wait on the GCNR rockets until a market exists.

In the meantime, we should be able to build some very nice first-gen super-boosters by chaining a few of these babies together into a second stage. Once you have the OOMPH to get the rocket off the ground, you can ditch the first stage and coast a massive amount of cargo to orbit on your afterburning engines (~500 Isp). Once sufficient velocity has been built up, you can drop the afterburning and take the cargo the rest of the way on ~900+ Isp engines.

Lets build this then and send it up in one piece:
http://www.nuclearspace.com/a_liberty_ship.htm

The US didn't develop any of the technologies you mentioned, as none of them were actually built.

Really? Let's go through them one by one:

1. The Orion project did testing on the concept, and developed the necessary nuclear explosives (i.e. Pulse units). The declassified test video that convinced Von Braun to support the Orion concept can be viewed here.

2. The NERVA engines were considered ready for upper stage use despite the ablation problem. The program was only cancelled after the plans for interplanetary missions were cancelled.

3. In 1964 the Tory-IIC engine of the Nuclear Ramjet was fired for five minutes. The technology was successful, but the Pentagon had second thoughts due to the arrival of ICBMs.

4. Skylab was in orbit from 1973 to 1979. Generally considered a "successful" space station. The station was allowed to reenter after the focus shifted to the Space Shuttle project.

5. The Saturn V was flown 13 times with a 100% rate of success. Of those flights, seven boosted Apollo missions that landed on the moon.

In other words, most of this technology really did exist. :-)

Articles like this make me look forward to the 1960's.. They were really advanced..

There is some truth to this. The US developed *amazing* levels of space technology in the 1960s. Take a look:

8,000,000 tons from ground zero to anywhere in the Solar System
Plenty of power for regular Moon trips
Jets with unlimited range (Okay, the actual design of this one was a little scary. Still, the principles are sound.)
Complete Space Station in one launch
118 metric tons to orbit

Now all of it has been buried and forgotten. Advancement? We've buried our collective heads in the sand. That's why Bush's CEV program actually makes sense. He must have listened to his NASA engineers for a change, because the CEV is a staged program that is predicated on using existing technology to build a space infrastructure. No waiting for someone to invent the Starship Enterprise, we're going NOW. And to do it, we're pulling out many of the bits of technology that we forgot. I don't know about anyone else, but I'm excited about this program. :-)

... they make nothing but promises. Typical bureaucracy.

Opening up real space exploration would be simple: make it legal for private companies to build nuclear thermal rockets.

We're talking real space ships here. With that much power, you can afford to make them big, redundant, safe, and reusable. No more wimpy foam and composites - build it out of steel and have more engines than you need.

Forget the Ramjet, I think you meant Scramjet ala the X-43.

I'm still not so sure about the Scramjet. The engine itself is a great idea, but the structural requirements are terrible. Even a minor flaw in the surface of the vessel would lead to catastrophe.

The grandparent probably has it right. If you use Jet engines to get to a higher altitude, the efficiency of nuclear thermal engines can take you the rest of the distance without having to go hypersonic in thick atmosphere.

Interestingly, the "best" solution may even be a ramjet engine. Since a nuclear engine can run on any fluid, what more efficient method exists than pulling oxygen from the atomosphere? And if you afterburn with hydrogen, you're going to get one hellva kick in the pants. (Alternatively, you can turn it around and heat the hydrogen while "burning" the oxygen")

Amazingly, we already have the engine to do this. Pratt & Whitney's TRITON engine is the perfect solution. As a "tri-modal" engine, it's capable of three modes of operation:

1. Low atmosphere afterburning for high powered launches.
2. Upper atmosphere and orbital transfer propulsion using pure hydrogen fuel.
3. Low fission rate "idle" mode which produces ~200 kW of power. (More than enough for onboard systems.)

The implications of this engine are staggering. Thanks to the tungsten clad design, it can be used anywhere without polution. Which means that we can have a single engine type that can not only produce massive thrust on takeoff, perhaps even produce the much covettd and highly efficient ramjet. (Rocket scientists love the idea of taking oxygen from the atmosphere, but don't normally want their rockets spending enough time in the lower atmosphere to make it worthwhile). But also an engine type that is highly efficient in upper-atmosphere and "space" areas. Plus, the craft can ditch heavy batteries and fuel cells in favor of drawing all its power from the engines. That power would even be available for electrical manuvering thrusters so that the amount of propellant carried can be reduced. Thus some of the weight you pay for in heavier engines can be regained in reducing redudant systems.

If we're going to get a bird in the air in the near future that can get people to orbit cheaply and safely, nuclear is where my money is.

Here is a GREAT article detailing a hypothetical design for a fully resuable, non-polluting nuclear powered rocket based on the Saturn-V form factor. The rocket would carry 1000 TONS of cargo to orbit and return intact to a powered landing.

Briefly, the nuclear rocket would use a gaseous core reactor called a "nuclear lightbulb" -- a quartz bulb containing a cloud of uranium gas, which would self-heat by fission to about 25000 C, glowing intensely in ultraviolet. Liquid hydrogen propellant pumped around the outside of the bulb would absorb the UV and become a superheated gas that shoots out of the rocket nozzle.

This is not a mere lifting body, it's a complete vehicle, a true rocket ship right out of the golden age of sci-fi, with enough power to lift an entire space hotel in one shot, or a hugely equipped interplanetary mission. Great stuff.

You mean Like This?

On a related note, a few words about nuclear rockets. Back in the 50s and 60s some people, mostly science fiction writers, fantasized about nuclear powered rockets. In the 60s there was an actual prototype engine called NERVA. The idea was simply to use the reactor as a heat source to superheat a gas which would shoot out as rocket exhaust. The main drawbacks were the weight of the reactor core, the maximum temperature of about 3500 degrees C, and the radioactivity of the exhaust.

Here's a really interesting article that describes a design for a 100% reusable, non-polluting nuclear rocket based on the Saturn V form factor, capable of lifting 2 million pounds of cargo into orbit and returning to a soft landing. Just like in the old sci-fi movies. The design involves a gaseous core reactor, sometimes called a "nuclear lightbulb." It consists of a quartz bulb containing a cloud of uranium gas such as uranium hexafluoride, confined the center of the bulb by a buffer gas swirling around it. By adjusting the movement and pressure of the buffer gas, the compression of the UF6 can be finely regulated. When it is compressed to a critical state it heats up to about 25,000 degrees C, glowing intensely in the ultraviolet. Liquid hydrogen propellant pumped around the outside of the quartz bulb absorbs the ultraviolet light, becomes superheated, and shoots out of the nozzle. There is no leakage of radioactive fuel and no irradiation of the hydrogen. Completely clean burning. Such a rocket could burn for immensely longer times than any chemical rocket, providing the speed to get a manned mission to mars in a couple months. And not a skimpy mission, a spacious vehicle carrying 1000 tons of equipment, supplies and radiation shielding. Building a rocket like this wouldn't require any far-fetched technology, just some dedicated engineering.

I have never been a fan of nuclear reactors, but this thing sounds really good to me. The gaseous core has tremendous safety advantages over a solid core. The criticality of a cloud of gas is much easier to control and is to some extent self-regulating. For example, the problem of "hot spots" would not exist, because in gaseous form any part of the UF6 that overheated would expand, losing pressure and quenching itself instantly. The author describes several safety features, both active and passive, for letting the gas depressurize into a storage container extremely fast. Even if a gas core nuclear rocket exploded in the atmosphere, it would release a small fraction of the amount of nuclides from a single 1950s H-bomb test.

There have been at least three Russian nuclear-powered RORSATs that have fallen to Earth, one into Canada in 1978.

Not sure how big the Russian satellites are compared to this, though.

I think OP meant a propulsion system we could actually BUILD Einstein, that means we'll have to be able to afford it too.

You sir, are obviously an idiot who either can't read or can't be bothered to read. We DID build nuclear thermal engines. They were done. Ready to fly on the Saturn V. They simply weren't needed as the time, because the LHOx engines matured faster. Nearly ALL Mars missions call for NTR engines, which is why the TRITON got built.

As for nuclear pulse propulsion, most of the work has actually been done, including tests to verify the basic concept. (Test Video) Von Braun himself was a big proponent of launching a mini-Orion on the Saturn V. His idea was that the V would get things to orbit, and the Orions would take them to the solar system. Too bad our government stabbed him in the back by dismantling the Saturn V program...

It always amazes me how people will happily chime in with criticizim even in the face of overwhelming evidence. No wonder you posted as AC.

without some new propulsion technology i doubt even by 2029 we will have this option.

New propulsion technology? You mean like Nuclear Pulse, Nuclear Thermal (also in Trimodal for low atmospheric work), Nuclear Salt Water, M2P2, and hundreds of other mature, semi-mature, or proposed methods that we haven't used because it's "too damn expensive to get off this rock"?

Propulsion is *not* the problem.

Hey, what about http://www.nuclearspace.com/ ?
Where is the problem with their plan?

On the other hand, NERVA was considered to be possible and was canned over cost. We could do the necessary job with chemical rockets and that was good enough... But basically, the theory is that if you build a few of them to offset development costs somewhat, a fleet of reusable very heavy lift vehicles that can bring useful masses into orbit could be built and you could take them off from and land back in the middle of B.F. nowhere at the end of a serious (meaning solidly built) road in the middle of a wasteland, where they would be serviced.

Anyway smarter people than myself (I'm at least no dummy) think that it could work fairly reliably because it's a simple design, and that it would be sufficiently clean. And, it doesn't involve blowing stuff up.

I still think we should be expending as much effort as is useful on space elevator development. Right now that means materials science. However, you don't build this thing from the ground up. We need a fairly significant mass at the other end of the tether, and we have to be able to move the thing around, so you're talking about fairly serious facilities. We also want to be bringing approximately as much mass down as we are sending up, and in order to do that we need to be able to have something to bring down. To me that implies asteroid mining, which requires a lot of heavy equipment... Regardless, a very heavy lift vehicle is something of a mandatory step in any major space-related endeavor.

From what I understand, Orion's output involves a lot of EMP spread out all over the atmosphere. I imagine that might have somewhat severe repercussions where weather is concerned. Even the cleanest bombs available would be unacceptable for one reason or another, at least if you were planning to do it more than once.

When somebody mentions the shuttle program ending, I never miss a chance to plug nuclear rockets. I know it's the "N" word, but read this fascinating article detailing a design for a fully reusable, non-polluting rocket ship based on the Saturn-V form factor. Powered by Gas Core Nuclear Reactor engines emitting only non-radioactive hydrogen, the ship would be capable of carrying 1000 Tons of cargo into orbit and returning an equal amount of cargo to a powered landing. For comparison the shuttle's cargo capacity is less than 30 tons.

Good chance to slip in a plug for heavy lift rockets powered by Gas Core Nuclear Reactor engines. Here is a really interesting design for a fully reusable, non-polluting nuclear rocket based on the Saturn-V form factor, which could lift 1000 tons of cargo into Earth orbit (for comparison, the Space Shuttle can carry 30 tons) and return to a soft landing. It's a fully reusable spaceship that could haul up entire resort hotels (not just "inflatable modules") in a single trip.

Another great use for GCNR rockets would be interplanetary trips such as a Mars mission. Their cargo capacity would allow for a tremendous amount of supplies and equipment. Transit time would be half that of a conventional ship, reducing the effects of prolonged zero-gee and cosmic radiation exposure, and a host of other problems. The ability to make a powered landing on Mars would eliminate the need for an aerobraking system, Apollo-style lander/return combination or other engineering. The crew could fly there, land, take off and return home in a single vehicle, just like in all those old black and white space movies.

After all, while orbital assembly may seem cool, it doesn't seem very cost-effective yet.

It will work a whole hell of a lot better than on earth assembly. To get to lunar orbit, you don't have to worry about earth gravity or anything. You won't need a smooth skin either. It could look like a flying pig and be as ugly as you wanted. You also don't have to worry about the thing staying intact and not getting damaged on the way up.

As for a heavy lifter, That might be what heavy rockets are for. Though I wouldn't mind this: http://nuclearspace.com/a_liberty_ship.htm

Here is a fascinating article describing a design for a heavy lift rocket based on the SaturnV form factor, but using a Gas Core Nuclear Reactor engine. Non-polluting and completely reusable, it would lift 1000 tons of cargo into orbit -- enough to take up a space hotel in one go -- and return with an equal amount of cargo to a powered landing. Compare that to the shuttle's 30-ton capacity. Interesting reading, even if you have a nuclear=evil filter. It would be cool to see those beautiful behemoths flying again.

http://www.nuclearspace.com/A_PWrussview_FINX.htm

Gas core. Fun stuff. :~)

/annoyed by uninformed sheep

May be they will use some alternative cheaper form of energy in the near future.

it's called nuclear fission. see here for details: http://nuclearspace.com/a_liberty_ship.htm

And no, this does not involve blowing up atomic bombs beneath the ship.

You asked for it, you got it: 2009 Mars Rover will be Nuclear Powered
http://www.nuclearspace.com/a_2009_Rover.htm

On the subject of powerful boosters, here's a long but interesting article about nuclear powered rockets. It describes a non-polluting, 100% reusable rocket powered by seven Gas Core Nuclear Reactor engines, which could lift 1000 TONS into orbit and return to a powered landing.

What the launch-it-to-the-sun philosophy has going for it is that it rightly assumes space transportation will get cheaper and easier in the future. Nuclear power itself could be the key to getting rid of the waste. For example, here is a detailed article about a rocket design using a Gaseous Core Nuclear Reactor engine that emits no radioactivity itself. [It's a 12-part article. Skip ahead to Part 6 if you just want to know how it works.]

The rocket he describes, based on the Saturn-V form factor, would be able to lift 1000 tons of payload into Earth orbit. For comparison, the Space Shuttle carries 30 tons. Such a rocket, capable of hauling up an entire space hotel in one go, could easily carry along a few hundred pounds of encapsulated nuclear waste as incidental cargo on each trip. Once the stuff is in orbit we could periodically send bulk loads to the sun. There's always the possibility of something falling to Earth, but the author mentions that it would take many such incidents to equal the amount of nuclear material released into the atmosphere in a single 1950s bomb test.

Getting nuclear waste away from the planet is not an insurmountable problem, it's just an engineering project that eventually will be tackled and accomplished. Our storage goal should be merely to keep the stuff secure until then. Dreaming up ground storage schemes meant to last thousands and thousands of years is a big waste of effort.

Nuclear power could also fuel a vigorous space program
Please read before passing judgment: Liberty Ships

http://www.nuclearspace.com/a_liberty_ship.htm

And I want mine red, with go faster stripes on it.

http://www.nuclearspace.com/A_PWrussview_FINX.htm is correct link. Bush spends money on space, kerry wants to give the money to the poor.

http://www.nuclearspace.com/A_PWrussview_FINX.htm

http://www.nuclearspace.com/A_PWrussview_FINX.htm

I think Gas Core is the way to go. As the article mentions, a solid core reactor engine is expected to have a specific impulse of only 800-900 seconds, compared with 1500-2000 for a Gas Core engine of the closed loop type (no radioactive emissions). This translates into heavy lifting capability. As the article says, the solid core engine weighs to much it is only useful for vehicles already in orbit, so it would have to be lifted up in pieces by other ships. For really grand-scale work, like putting factories and hotels into space and hauling significant loads to Mars in a reasonable time, we need the big kahuna lifting power of a gaseous core engine.

Here is a highly detailed 12-part article that discusses a Saturn-V size gas core rocket that would lift a payload of 1000 TONS from the ground to orbit and return with an equal payload to a powered landing. Skip the first 5 parts (author's justification of why to build it) if just want to know how it works.

yeah right, they have a whole newsroom doing fact checking for you

http://www.nuclearspace.com/A_PWrussview_FINX.htm Enjoy

It's the most powerful rocket ever built.

Correct.

It's the only vehicle ever to carry people to another world.

Yep.

It is a fantastic technical achievement.

It's also old. It was neat when everyone was in grade school (or perhaps in front of the television in '69), but it's old news now. I show my four year old son videos of the Saturn V, moon landings, Shuttle Launches, and the only Buran launch. He thinks that it's really neat stuff, but I know that he'll be frustrated by the lack of progress when he gets older.

Of course, most people don't know that. Half can't read. How could they know about the Apollo program?

An exageration. Yes, there is a serious education problem. But how do you expect those who "fall through the cracks" to become interested in getting an education if you don't give them something to strive for? The Saturn V was yesterday. There are no more flights. The future is here. Let the kids dream about being the first person to set foot on Mars. It will give them a goal in life.

Basically, if we can't make a business case for it, i.e. if we can't sell it for a 50,000% profit, it won't happen. Oh, we might get a magnanimous billionaire to throw a few million around here and there, but by and large, our society is stagnating. Nobody cares about anything unless it's a big pile of money.

Truth be told, margins have been shrinking for *years* and it has been tougher and tougher for businesses to make money. Space represents a new horizon for technological development, and a place to potentially make millions, billions, perhaps even trillions. SpaceShipOne was just the first step. The current design will kick off space tourism. Then Bigelow will provide cheap launch capability. From there Scaled or someone else provides manned space craft. Bigelow provides the space stations.

Next thing you know, we've got companies mining asteriods for some serious profit. Platnium, Gold, Silver, Uranium, etc. all exist for the taking. Even Iron becomes much more valuable as it's already out of Earth's gravity well.