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NASA's Journey To Mars May Use Nuclear Rockets (blastingnews.com)
MarkWhittington writes: NASA Administrator Charles Bolden has been making the rounds of congressional committees, defending the indefensible, that being the latest Obama space agency budget proposal. Thursday it was the turn of the House Science Committee to complain to Bolden that the budget underfunded the Journey to Mars and to vow that more money would be forthcoming. One of the other complaints Congress has been making is that NASA lacks a plan to get people to Mars, scheduled to happen sometime in the 2030s. Bolden was coy, suggesting that the time was not right to start firming up architectures and missions. However, he did drop an intriguing hint that a nuclear thermal rocket engine being developed at NASA's Marshall Spaceflight Center may take people to Mars quicker than chemical rockets.
Quick, hide the sensitive people like children and, people who are less rational and more spastic than children like MDSolar! Somebody used the word NUKULAR and there might even be a RAYDEEASHUN!!
We should ban all things nukular from space because polluting natural, artisanal, organic, and non-GMO space with radeyashun would be a crime!
AntiFA: An abbreviation for Anti First Amendment.
ESA: We made it to mars america! our rover is collecting samples and data.
ISRO: America! we need some help analyzing these samples! can you send a rover to kindly do the needful?
Russian space agency: Da. We are needing help with this outpost America. New supplies and ships needed for our colony.
NASA: look guys uh....we're in our fifth government shutdown, the supreme courts been vacant for 3 years, I think...i think most of our drinking water is lead these days and we just pledged another 800 billion to the terror war and the great wall of mexico. But if you can somehow work Mars exploration into religious freedom i think we can keep the radio comms up another month.
Good people go to bed earlier.
NASA had a nuclear thermal rocket program called NERVA back in the 60s (itself in part inherited from the US Air Force): https://en.wikipedia.org/wiki/NERVA
The program successfully developed a nuclear thermal rocket engine (successful test-firings and everything), and there were plans to build a Saturn V with a nuclear upper stage, but the program was killed by Congress because of the old "give a mouse a cookie" problem. NTRs are basically only useful for sending enormous things to Mars (or other planets), like human colony modules, since the engine and tankage is so heavy that the efficiency only becomes a benefit when the payload is even bigger. The fear was that if Congress let NASA continue NERVA development, it would lead to greater pressure for human Mars missions, which would be expensive (though I'm sure a campaign of human exploration of Mars pales in comparison to the cost of the campaigns in Vietnam and elsewhere -- and it will certainly pay off more technology dividends and look better in the history books).
We shouldn't pollute space with hard radiation!
I can see environmentalists objecting with something like that.
Who you calling fictional, Anonymous Cavedweller?
https://en.wikipedia.org/wiki/NERVA.
Sheesh...
Wow, finally there is someone who is even more clueless than MDSolar.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Wow...
To think that your vote counts as much as normal people's...
Mars is barren, extremely inhospitable, wasteland. Why are they in such a hurry to send meatbags there ?
No way. First there are international laws and treaties preventing ANY nuclear devices I space.
Way. In fact, it was already done long ago. The Voyager space probes have a nuclear power source.
Nae king! Nae laird! Nae yurrupiean pressedent! We willna be fooled again!
>> may take people to Mars quicker
Slowing down to catch the planet, getting back off the planet, and returning back to earth would all seem to be bigger problems.
I believe the treat is nuclear WEAPONS... This is not a weapon, and besides which there have been numerous nuclear devices launched in recent years, New Horizons was powered by a radioisotope thermoelectric generator, which has PLUTONIUM!!
First there are international laws and treaties preventing ANY nuclear devices I space.
No, there aren't. The Partial Test Ban Treaty of 1963 bans nuclear detonations in space, which killed the Orion project (not that it would likely have gone anywhere anyway).
We launch nuclear devices into space all the time; that's how deep-space probes get their electric power. The recent proposal is to use nuclear heat generation to power a rocket, and the treaty is just peachy with that.
We need to launch a few nuclear tugs. They can be used to move spacecraft up to higher orbit, so we don't need to use large expendable boosters. Just get the craft into orbit, meet up with a tug, and push it to a higher orbit or even escape velocity. Then the tug can return to low orbit to be refueled and ready for the next mission. The tug still needs propellant, it just uses the nuclear power to heat it for propulsion.
A 0.01g constant acceleration ship gives you the Solar System.
A ship capable of a constant 0.01g acceleration would be a game-changer. Break the steps down as X-prizes. Build a 0.001g ship. Scale it up to a 0.005g ship. Next step is get it to 0.01g and you can reach Mars in three months and anywhere out to Pluto in just less than a year. First place to go? Prospecting the asteroid belt would be my vote. Find useful stuff, use it to build more useful stuff.
>>>> Mars has like .6 the atmosphere of Earth
>> you might want to check again
I believe the poster meant: "The highest atmospheric density on Mars is equal to that found 35 km (22 mi) above Earth's surface. The resulting mean surface pressure is only 0.6% of that of Earth (101.3 kPa)."
We can learn a lot from inhospitable places and even more from figuring out how to get there and stay alive.
That's circular reasoning. We don't have a need to learn to stay alive if we're not going. What are those other "plenty of good reasons" ?
Nobody is asking you to go
That doesn't mean I like to see already small public funds wasted on missions with low return on investment.
There is a plan that would get us to Mars soon and in the budget we have. But Congress wouldn't like it because it wouldn't use their favorite pork rocket (SLS), and possibly not even Orion (which is a less-bad idea than SLS is, but still ultra inefficient).
But the fact is that we didn't even have a "plan" to get to the Moon when JFK made his Rice University speech. Or we did, but it was wrong. The original plan was to use direct ascent of the Apollo command module off the surface of the Moon and go straight back to Earth. But such a plan would've required a launch vehicle much larger than the Saturn V. Instead, we used Lunar Orbit Rendezvous, which allowed us to use just Saturn V. And of course, we had to shut down Saturn V production during the Apollo program because even Saturn V was too expensive and unsustainable. SLS is even worse, as it uses old Shuttle parts (developed in the 1970s, for God(dard)'s sake!) which were originally intended to be reusable but now we're just throwing away (the worst of both worlds... the upfront cost of reusable parts and the expense of throwing the whole thing away each time), and so we can afford to fly just once every other year (and each Mars mission will require several launches).
We can explore Mars entirely with EELV-class launch vehicles. Atlas V has a 7.2 meter fairing available, Delta IV Heavy can put about 28 tons in orbit (enough for the largest "single piece", provided we use docking... but no orbital assembly required), Falcon Heavy will launch within a year (it starts testing in Texas soon), can put over 50 tons to orbit (more with cross-feed), and Vulcan (the successor to Atlas V and Delta IV being designed now with Blue Origin's BE-4 engine) can handle a 8.4 meter fairing (same as SLS) and in Heavy configuration could also handle at least 50 tons to LEO.
We can also use either SpaceX's Dragon or Boeing's Starliner capsules, which are much more efficient, to get crew to space and back. The actual vehicle to bring astronauts to Mars vicinity wouldn't actually bring Orion along anyway, as the current plan is to rendezvous in a distant retrograde lunar orbit.
Our human exploration funding is dominated by SLS and Orion, both elements of which are way too expensive and will be available in full form much later than EELV-class vehicles (available now, with twice the capacity available sooner than SLS's first test launch) and Dragon/Starliner (set for 2017 crewed debut). Instead of wasting our funding on two elements we don't need, we could spend the money on a small transfer vehicle (perhaps using solar-electric propulsion, but chemical rockets would work, too) and a Mars lander/ascent vehicle in addition to surface elements.
Instead of duplicating effort, we should focus on what we actually need to do Mars. Lander and transit hab.
Congress (or rather, those in Congress who make a stink about space exploration because it provides jobs in their districtrs) knows SLS/Orion aren't strictly required, knows they're very expensive (which is why they're supportive of them... more cost = more jobs in their district), what they want is to somehow cement SLS/Orion in place so their districts are guaranteed to receive funds for decades. That's really the whole issue, here. ...there's also a huge revolution going on in spaceflight. Truly affordable reusable vertical takeoff, vertical landing (VTVL) rocket technology is now scaling up to enormous size. You have SpaceX with reusable flyback boosters for Falcon 9 and Heavy, plus Blue Origin tooling up for their own VTVL orbital vehicle. ULA (who makes Atlas V and Delta IV) is developing orbital refueling technology with Vulcan, which is hugely enabling. And we're just getting started. SpaceX has plans for an enormous reusable launch vehicle also using methane/LOx technology and intends to send people in 2025 (perhaps using Falcon Heavy and a Raptor-based lander, perhaps using the enormous vehicle). This is far earlier than any NASA plan could possibly hope for given its budget and Co
Don't get me wrong, nuclear does have some interesting avenues open to it. I just don't see nuclear thermal as among them.
I'm actually a big fan of fission fragment propulsion; I think that's a rather clever concept. It's about as high specific impulse as one could possibly get out of fission, and much higher than that of most fusion concepts, the vast majority of which we can't build today. In fact, I can't recall any fusion concept that beats it, except for fusion-driven photonic propulsion. Fission fragment concepts proposed thusfar provide thrust levels not that much less than VASIMR, but ISPs of over 100k sec.
Further in the future, I've pondered the concept of using Jupiter as an antimatter factory. Jupiter corrals the highest density of high-energy particles in the solar system into broad belts. They're of course still far too low energies and densities for antimatter production, but with a large enough magnetic pinch feeding it, I wouldn't be surprised if a realistic system could be designed to produce high flux beams in the dozens to hundreds of GeV energies required over a good-sized target (note: I haven't attempted to simulate this!). If you can get nature to provide your ion beam for you - a large/intense enough of one - then the concept of using antimatter as fuel could potentially become plausible. Here on Earth, the energy required to generate such beams renders antimatter implausible for direct spacecraft propulsion.
You can't change that... by gettin' all... bendy.
While the Outer Space Treaty of 1967 does specifically ban nuclear WEAPONS in Article IV, as mentioned elsewhere, nuclear power, either as a power source or propulsion source is not banned.
This could become interesting if someone built an ORION-drive spacecraft. Even so, calling the bombs in question "impulse devices" would technically make them allowable under the Outer Space Treaty. . .