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Maybe just use a nucular rocket engine...

http://www.lascruces.com/~mrpbar/rocket.html

I am not sure how you can use the atmosphere to get the first stage going, unless you mean use an airplane to do the first 50,000 feet (~10 mi) and 500 mph.

First stage Saturn V got about 40 miles up at about 5,000 mph carying 130 tons using 2200 tons of propellant.

I have seen suggestions that ~46,000 mph or 13 miles/sec would get you into orbit. At 100Gs for 20 seconds you get up to 64,000 feet /sec and travel 400 miles down range. A 400 mile long vacum sealed mag-lev launcher maybe? Maybe I dropped a OOM (order of magnitude)...

A 50 mile launch may be much more reasonable...

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.

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.

Can't find anything related to nuclear jet turbines, perhaps they were building a rocket plane? or a space launch vehicle?
http://www.lascruces.com/~mrpbar/rocket.html

our space program was originally going to be launched from idaho, until someone realized that launch would be easier the closer one got to the equator. and INEEL has the largest stockpile of radioactive waste too, because remember it's all in 'temporary' storage.

The link below mentions two different technologies, but it looks like the nuclear fuel is used to heat Hydrogen. Seems like this would still be riskier in the event of a crash than standard LOX rockets.

http://www.lascruces.com/~mrpbar/rocket.html

So, I guess there are nuclear rockets, but the nuclear material isn't used as a propellant which was my impression from the post.

/annoyed by uninformed sheep

Sounds like a gas core nuclear thermal rocket.

Los Alamos has been researching this concept as an improvement to the proven solid core nuclear rockets. (Nuclear Rocket Overview)

It operates essentially as you've described, with a critical mass of gaseous uranium swirling in a vortex around the center of a rocket engine. Hydrogren flows through the center of the vortex, is heated, and expelled.

No working prototype has been built, largely because of the difficult fluid dynamics involved, and the problem of preventing your uranium from flowing out the nozzle with the hydrogen. A working gas core rocket is expected to have ~3000s Isp (versus ~1000s for solid core), and slightly lower thrust than a similar solid core rocket.

Although there are techniques for safely testing nuclear rockets on earth and some nuclear rocket testing going on, space researchers are still a bit too timid to go ahead with a nuclear rocket program. The advantages of nuclear rockets over conventional rockets include massive reduction in rocket mass and increase in specific impulse. Testing of nuclear rockets on the Moon (which is already highly radioactive due to constant bombardment from the solar wind) will prepare us for a fast journey to Mars, i.e., weeks not years. Then we can make multiple trips and build massive ships for journeys to the outer planets.

Ha, while that is true for the Earth as a whole, it might add politically significant amount of uranium isotopes to some dude's backyard in Florida and that counts 100x more than all the output of coal plants combined globally.

Did you know that uranium is one of the most common substances on Earth? You probably already have some in your backyard. Raining some from an engine would NOT increase it by that much. It certainly wouldn't kill you in the time it takes for the nuclear energy commission to clean up your neighborhood.

Did you know that old style X-Ray machines would give you up to 10 REMs of X-Ray radiaition per X-Ray? Modern digital machines give off only about 10-100 millrems, but if you are older than 15 you may have had an X-Ray from an older machine.

You'll note BTW, that it did not instantly kill you or cause your skin to melt. In fact, doctors considered it quite safe as long as they made sure not to give you too many X-Rays.

When it comes to nuclear power, the real dangerous stuff is the heart of a very large reactor. Older reactor designs would keep hundreds of pounds of material under pressure so that they could produce large amounts of power. In the case of a melt-down and boiler explosion, a lot of hard radiation would be exposed to people near by. (And I mean people within about half a mile. Radiation falls off at the same rate as light, so give it just a little distance you won't get any more than you would from your CRT.)

Here's the upside about the "hard stuff". It doesn't last. In order to be energetic enough to kill someone, it has to have a very short half-life. Within an hour, a reactor's core has already lost much of its most potent stuff. Within a few days it may even be safe enough to approach. Within a month they could cement over it and forget it existed.

I should probably mention that modern reactors can't have a boiler explosion like Chernobyl. Those designs were deemed unsafe long before the incident, and were decommisioned here in the US. Chernobyl OTOH, was built with *decreased* safety precautions because the Russians thought they were unnecessary. Contrast that to Three Mile Island which shut down exactly as it was supposed to.

Some interesting statistics for you. Currently, there are ~500 nuclear reactors in the world, plus the 50+ used by US Navy Vessels (8 on the Enterprise alone, 2 on a standard Nimitz carrier, and 1-2 on each nuclear sub), plus about 550 research reactors operating worldwide. Nuclear reactors are well understood things at this point.

I must admit that from what you are describing the engine would look completely different from what I have seen in some old magazines, it must be some completely new concept, if you have some links to sites (with pretty diagrams for ignoramuses) I would appreciate.

Wikipedia explanation of various proulsion methods

NERVA and GCNR engine descriptions

You're probably thinking of NERVA engines. NERVA engines would melt off the back of a rocket and drop from the sky like a rock (a very heavy rock) if they were to melt-down (although they run pretty close to melt-down normally). Gas Core Nuclear Rockets (GCNR) use a uranium plasma vapour for heating the propellant. This is in many ways easier to contain in an emergency than a tradiational nuclear pile.

BTW, I should probably point out some of the safety features of nuclear rockets. For one, they have more power, so they can be built of more traditional and well understood materials. Many chemical rockets go for exotic composites to keep weight down. The other advantage is that the fuel is what cools the engine. In the case of a runaway nuclear reaction, the turbopumps can deliver more fuel to cool the reactor

Shame those projects got dropped....

Tho' I must admit, given the chance to work on something like that it would be hard to resist... :-)

Considering the risks (meteorites, radiation, low grav environment,
isolation), a 2 year mission to Mars (aka going to Mars on a prayer) will never
happen, not when there's the potential for the American public to watch
helplessly as a bunch of astronauts die a million miles from home over the
course of agonizing weeks without any hope of rescue, and especially not when 2
of the last four Mars lander missions have failed.

Nuclear rockets might shrink the time for the trip from years to a couple of
months. We have trouble doing tests of those here on Earth because their radiation output would
make Chernobyl look like a minor leak, so any flight testing need to be conducted in space,
where the environment is already high in radiation. Of course, you'd still need to launch
the reactor fuel into space....

Nuclear Rockets Page
(I can't vouch for the authoritativeness of this material but it looks
interesting).

One of the earlier "nuclear" test engines was this puppy, the nuclear thermal rocket. If you have seen a video of it when it was being tested, you would know that that thing is one mighty beast. The soviets also attempted to design one (both the Soviet and the American versions had the purpose of getting people to mars) which looks a lot cooler. I would love to have a model of that sitting on my desk. :)

Anyway, this nuclear propulsion is somewhat related to the newer Xenon method albeit with lower specific impulse but much higher acceleration.

The U.S. had a perfectly good functioning nuclear ramjet and abandoned the project. There were also fission rocket engines built, quite powerful ones.

<sarcasm> I wonder why those projects got dropped.. ?</sarcasm>

Tho' I must admit, given the chance to work on something like that it would be hard to resist... :-)

It seems extremely conservative to me that Russia would take 30 years to get to Mars, especially considering their stated plan is to build a reactor - they'll get to Mars faster if the reactor is in fact what gets them to Mars in the first place.

The U.S. has had a working nuclear rocket engine for forty years, according to a PDF on the ROVER/Nerva project off this page. These are relatively simple engines which shoot hydrogen out the back.

Of course the reference to "already built" is bizarre, who cares if it is already built if they are going to take 30 years to do it? No reason to mention that unless maybe they are talking about tested submarine reactors.

Of course the U.S. has a deal according to this March 2003 article to get Russian nuclear rocket fuels for the nuclear rocket program of Project Prometheus through 2009.

This pdf says that using the NERVA rockets of the 1970s we could get to the moon in a day, or to Mars in 4 months. The article by a Los Alamos researcher is interesting as it talks about the social problems versus technical problems. In all it seems that the nuclear rocket costs half as much, is twice as powerful, and is safe (at least from this paper it seems that reactor core products stay in the reactor). Also from about page 21 there is an interesting section on radiation and human exploration.

It talks about using a gas core nuclear rocket (GCNR) in which we are talking about how to shield crew from radiation in flight, not on the ground, but that this will mean we can get to and from Mars in much less than NASA's planned (1998) mission of 3 years. With a specific impulse of over 3000 seconds, a GCNR ship can have a 3 month transit to Mars, 2 months on the planet, and 4 months back - thus reducing psychological stress factors by keeping the mission to 6-7 months' duration.

There is also the physical deterioration from a long flight.. Apparently the current U.S.-Russia program is aiming for even better, perhaps 2 months each way using small reactors for an unlimited fuel supply and three times better propulsion.

More info:
link
link
link
pro-nuclear space space group with more information

It seems extremely conservative to me that Russia would take 30 years to get to Mars, especially considering their stated plan is to build a reactor - they'll get to Mars faster if the reactor is in fact what gets them to Mars in the first place.

The U.S. has had a working nuclear rocket engine for forty years, according to a PDF on the ROVER/Nerva project off this page. These are relatively simple engines which shoot hydrogen out the back.

Of course the reference to "already built" is bizarre, who cares if it is already built if they are going to take 30 years to do it? No reason to mention that unless maybe they are talking about tested submarine reactors.

Of course the U.S. has a deal according to this March 2003 article to get Russian nuclear rocket fuels for the nuclear rocket program of Project Prometheus through 2009.

This pdf says that using the NERVA rockets of the 1970s we could get to the moon in a day, or to Mars in 4 months. The article by a Los Alamos researcher is interesting as it talks about the social problems versus technical problems. In all it seems that the nuclear rocket costs half as much, is twice as powerful, and is safe (at least from this paper it seems that reactor core products stay in the reactor). Also from about page 21 there is an interesting section on radiation and human exploration.

It talks about using a gas core nuclear rocket (GCNR) in which we are talking about how to shield crew from radiation in flight, not on the ground, but that this will mean we can get to and from Mars in much less than NASA's planned (1998) mission of 3 years. With a specific impulse of over 3000 seconds, a GCNR ship can have a 3 month transit to Mars, 2 months on the planet, and 4 months back - thus reducing psychological stress factors by keeping the mission to 6-7 months' duration.

There is also the physical deterioration from a long flight.. Apparently the current U.S.-Russia program is aiming for even better, perhaps 2 months each way using small reactors for an unlimited fuel supply and three times better propulsion.

More info:
link
link
link
pro-nuclear space space group with more information

Solar has a large energy investment and the panels, batteries etc are hard to recycle. Oil and coal are environmentally devastating in production as well as use (our largest local (Muja) coal station burns 12 tonnes a year of uranium, to say nothing of releasing radon etc); gas is better but shipping all of those big bombs around the country's just gotta have a sudden, loud environmental impact one day, hopefully not near any serious population. Wave and tidal generators muck around with the local ecosystem something chronic (as does Ocean Geothermal, but if you integrate fish-farms you at least get roughly twice the industry for the same amount of intervention). Nukes are quiet, clean, low-profile and produce small amounts of straightforward-to-manage waste.

If we were allowed to build proper nuclear rockets as well (get Burt Rutan to design them, not NASA), we could fling hundred-tonne loads of waste into the sun (or better still store it in a safe place (orbit/moon etc) for later re-processing) for an extremely low environmental cost. This is a question which has been studied to death, the answers are all to hand.

Stand by for a flock of "-1, Outrageous" mods from people who call themselves "green" but never actually think about the issues. They drive old, cheap, smoky, polluting cars and track dieback through the native forests they claim to protect. Here's a better way of approaching these things.