NASA's Journey To Mars May Use Nuclear Rockets (blastingnews.com) 224
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.
OMG! NUKULAR! (Score:5, Funny)
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!
Re:OMG! NUKULAR! (Score:5, Insightful)
This is why you can't have new nuclear plants. Instead of addressing the very real issues, you simply mock the people raising them.
In this case, there are also real concerns that are worth discussing too. The Russians have had a couple of incidents with their nuclear powered spacecraft. I'm sure NASA would take every precaution and it's probably fine, but then again you would hope they had done that with the shuttles too so it's something that needs consideration.
Re:OMG! NUKULAR! (Score:4, Insightful)
Because the "real issues" being brought up are not. There are not these serious issues, and nuclear is very safe. When there are very minor releases of radiation, mdsolar, you and others like you flip your shit like everyone is going to die. This is not a serious issue, and a properly upgraded/replaced plant will not have any of the issues that cause meltdowns. But let's demonize nuclear energy for causing less radiation release than coal in normal operation, or even heavy metal mining for wind and solar.
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IIRC the Ruskys considered flying a reactor in the 60s but never did. On their armed orbital base.
Your are thinking of a radionuclide battery. No moving parts, just a heat source and bi-metals.
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Marge also used the same line to "correct" Lisa...
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Re:Given this congress, not likely. (Score:4, Funny)
Are you kidding? All the ESA needs to do is have their rover re-broadcast a terrorist beheading.
Before you know it, the US will invade.
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Beheading? Man just announce that you found a strange black goo seeping out of the ground. They'll have an all Texan drilling crew up there in a matter of days.
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Thank you. I needed that laugh to end the work week.
And thusly, the tie goes off and the weekend starts.
What's old is new again. (Score:4, Informative)
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).
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We shouldn't pollute space with hard radiation! (Score:5, Funny)
I can see environmentalists objecting with something like that.
Just one of many problems (Score:2)
Speaking of which, has anyone figured out how to get someone to Mars without being killed by exposure to the natural radiation in route?
There are Top People working on it. But that is just one of several show stopper problems we'll have to figure out before a visit to Mars becomes viable. And if we want to stay there for any length of time there are even more problems to solve. Probably doable but it's going to take a while to work them out. The precise length of "a while" will be contingent upon funding and societal motivation.
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That's actually part of the reason for seeking faster transit times via better engines - to minimize the radiation dose to the crew, so that their health isn't compromised upon arrival. It's sort of an acceptance that we don't really have a good solution for it, and it might well be cheaper just to develop and deploy a better propulsion system (that benefits us elsewhere as well) than to launch a massive amount of shielding.
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As long as you clear the Van Allen belt first, otherwise it'll be more like a fart in an elevator. [wikipedia.org]
What's the rush ? (Score:4, Insightful)
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Why are they in such a hurry ?
We don't fully understand extinction risks or fragility of our technological civilization. Getting to Marks is the first step in establishing permanent colony there. This way humanity could survive mass extinction on Earth.
Re:What's the rush ? (Score:5, Insightful)
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Actually, the odds of backup surviving are excellent. We are not talking about intrinsic fragility or propose that humanity has a tendency to self-destruct. If that the case, it is probably irrecoverable. We are talking unexpected one-off events. That why we backup our data. This why we need a functional Mars colony.
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because if you system is too fragile to survive, what are the odds that your backup will survive?
That's a stupid comparison. A regular backup disk provides excellent odds, for very small cost. A functional, self sufficient Mars colony, would be expensive beyond comprehension, and extremely fragile, even without unexpected events. If you want a backup for unexpected events, I suggest we build several shelters underground, or inside mountains where people can hide until the worst is over. That's a lot cheaper than building something on Mars.
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That's a stupid comparison.
I agree, we shouldn't compare game-ending potential extinction of our species with slight harm of potentially losing some of your car videos.
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with humanity we need to reach 100% uptime
No, we don't, and we won't. We're all going to die, and our unique DNA patterns will fade away.
but if Western technological civilization collapses (as Mayan, Roman, Hindu, Byzantine, Persian civilizations did) for whatever reason, like being overrun by a Caliphate, humanity may not retain this technical ability.
The Martian civilization would collapse even quicker, and being in such a inhospitable environment, would be immediately sentenced to death. At least, if our Western civilization collapses here on Earth, there will be survivors to start another one.
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Because it's there (Score:2)
Mars is barren, extremely inhospitable, wasteland. Why are they in such a hurry to send meatbags there ?
Antarctica, the Mariana's Trench, the top of Mount Everest, the surface of the Moon and low earth orbit are all barren and extremely inhospitable wastelands and we've visited all of those. There are plenty of good reasons to want to put people on the surface of Mars too. We can learn a lot from inhospitable places and even more from figuring out how to get there and stay alive. Furthermore what is uninhabitable today may become a viable destination with an adequate application of technology. Nobody is
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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.
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Why are they in such a hurry to send meatbags there ?
NASA has announced that the first passengers to Mars will not be volunteers, but they will be drafted for the mission. You have no choice . . . you're on a one-way trip to Mars.
NASA's current picks are Hillary Clinton and Donald Trump.
That's why they are in such a hurry. Gotta get that rocket launched before November.
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may take people to Mars quicker is not the problem (Score:3)
Slowing down to catch the planet, getting back off the planet, and returning back to earth would all seem to be bigger problems.
Need nuclear tug in Earth orbit (Score:5, Insightful)
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Or, for current tech (we don't have any nuclear reactors designed for use in space at the moment), solar-electric tugs. But indeed, tugs are an idea that's long overdue. High ISP propulsion systems have tiny thrust to dry mass ratios, so launching all of that dry mass every time is a major waste when you could just be launching the propellant.
In the context of Mars, one looks at cyclers - craft designed to continually transfer between Earth and another body while hauling payloads, only needing periodic pr
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There is literally no part of this idea that makes sense. Either way you still need to get your propellant to orbit in some manner, and having your "tug" move up and down in the gravity well just wastes twice as much fuel (2x delta-v). Adding nuclear power to this solves no problems and introduces others. Plus it's not like you can just park it somewhere convenient and take it up and down like an elevator.
I don't think you thought this through. If you want a space elevator, you kinda have to build a space e
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Here's the part you're missing.
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Scenario 1: No tug.
Launch #1:
Earth: Launch spacecraft + heavy but efficient propulsion system + propellant tank + propellant for said system to LEO
LEO: Spacecraft + heavy but efficient propulsion system + propellant tank + propellant to MTO & capture to LMO
LMO: Spacecraft + heavy but efficient propulsion system + propellant tank + remainder of propellant to ETO & capture to LEO
LEO: Spacecraft ditches everything else (letting it burn up), reenters and lands
Launc
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See the difference? In the latter case, you don't have to keep launching the heavy but efficient propulsion system. It's as if all subsequent launches get a heavy but efficient propulsion system for free.
They don't get a heavy but efficient propulsion system for free. They get it for the initial launch cost, propellant, and more propellant to get it back to where it might be useful again. If your tug is heavy that would mean that it would need to be even more efficient to be economical. Without some plausible numbers to throw into a delta-v calculator I am afraid that I will remain skeptical.
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You only pay that *once* - only on the intial launch. Every time after that, yes, it is free.
1) You're seriously going to pretend that I didn't just write that?
2) The propellant mass is far less than the craft mass
1) It both starts and ends where it's useful (LEO).
2) The propellant cost for a system like VASIMR maneuvering b
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It depends on the ISP of the Tug right? If the tug ISP is 10x that of the alternative for the fuel mass you climbed out of the gravity well with then it would be a win to use the tug right before you start up you light the candle on your *really* dirty *really* high ISP engine.
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We need constant acceleration ships (Score:3, Interesting)
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.
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Better propulsion I'm all for, but it's hard to beat a constant drive for long distances with a burst of acceleration. Every day the constant-g ship with a measly 1/100g is adding the equivalent of 8.6g for about 100 seconds. Or 1g for 864 seconds. The delta-v just keeps adding up.
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Better propulsion I'm all for, but it's hard to beat a constant drive for long distances with a burst of acceleration. Every day the constant-g ship with a measly 1/100g is adding the equivalent of 8.6g for about 100 seconds. Or 1g for 864 seconds. The delta-v just keeps adding up.
No, it won't, because your constant-g ship will run out of fuel after a short time. Unless, of course, you come up with much better propulsion, which was my point.
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The better propulsion is implicit if you want a constant g ship (for any meaningful distance), so I think we are agreeing. I didn't make it explicit because it is implicit once you run the calculations that a chemical or nuclear-thermal rocket won't cut it due to fuel mass. To be more explicit, I'd love a propulsion system that can do better than 1/100g for months, but I doubt we will get there soon. A propulsion system that could do 1/100g is much more achievable with existing technology and a worthy go
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(Hint: short bursts are done because of fuel supply limitations)
No. We could very easily design a rocket engine that can sustain a slow burn for a long time, but it wouldn't be able to lift itself off the ground. For that, you need high acceleration. And once you have a rocket that can sustain that, you might as well burn it at a high rate until the fuel is gone.
It provides artificial gravity for the ship's occupants.
At 0.01 g that will be next to useless.
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You are confusing two different applications - escaping Earth gravitation and traveling in the space.
No, I'm fully aware these are two different applications. I'm just saying that rockets already carry fuel and a rocket engine to escape Earth gravity, so if you can use these for space travel, it will be more efficient. Unless, of course, if you come up with a much superior propulsion system.
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Now only if you could have one engine that imparts high thrust for getting out of the atmosphere... we'll call that "stage 1"... and then another separate engine for use once in space, which we can call "stage 2". And, when you change over to "stage 2" we can drop off all the empty fuel tanks and the engine from "stage 1", because it's dry useless mass that we won't need any more!
I'm sure nobody has ever thought of this novel method of optimizing a rocket before. Certainly not during Apollo.
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Explaining more and following up on MachineShedFred point. It's a given that you won't use a 1/100g constant drive as a booster toiget to LEO from Earth.
You are right - a 0.01g constant acceleration drive will take a while to get out of LEO. But it's still about 3 months to Mars. If we had a way to do 0.1g for a while that would be great. I just don't see it happening unless you use a nuclear-thermal or a chemical booster, in which-case your specific-impulse sucks. Maybe VASIMR, but even at the high en
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Do you mean - We need better propulsion technology for boosters to get all this nuclear stuff to LEO?
What I mean is that we need better propulsion tech in general. There's no advantage to limit our search to low acceleration only.
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Actually, it's not. A ship that can manage constant acceleration, even if the rate of acceleration is low will be able to attain higher velocities than a ship which is limited to short bursts of acceleration. (Hint: short bursts are done because of fuel supply limitations)
Read up on the Oberth effect [wikipedia.org]. A burst of acceleration in a gravity well can be worth considerably more than the same acceleration outside of the gravity well. It won't compensate for massively more delta-v (for example, if your constant acceleration propulsion can provide an order of magnitude more delta-v over the desired trip endpoints).
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This is one of the dumber things posted to slashdot. It's like suggesting that an over-unity device would solve our electric needs. If you have some magic box that never needs fuel, sure, you can go anywhere. In the real world your ability to go somewhere is limited by the rocket equation. Talking about spaceship engines in terms of acceleration is as meaningless as talking about CPUs in terms of gigabytes. You don't get to hand-wave away conservation of momentum.
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Nobody is suggesting that our constant-g rocket will run forever. That is obviously impossible. But it may well run for long enough to be useful, and better than a chemical or nuclear-thermal rocket.
Your argument about ignoring conservation of momentum is also wrong, as is your comment about the rocket equation. It's because of those two facts that we need really high ISP. That means nuclear. It probably means something like a fission-fragment rocket to get high enough ISP.
So go ahead, take the cheap-s
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Nobody is suggesting that our constant-g rocket will run forever.
The point is you're missing terms from your equation, and it's not sensible to describe a rocket engine in terms of acceleration alone: you need the other factors in the rocket equation: total mass, mass-to-fuel ratio, time, and effective propellant velocity. You can't escape dealing with those terms unless you have a reactionless drive, and that requires dispensing with conservation of energy. A "1G drive" is a meaningless concept, and I stand by the validity of my analogies.
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I'm thinking of things with very high ISP for all the reasons you are citing. The point I'm trying to make is that if we could build a 1/100g drive then we could do a hell of a lot, and low acceleration drives can accomplish lots.
So I didn't think your analogy was fair at all. It seemed, to be honest, the same kind of analogy used to prove that putting humans on the moon is impossible. It's like people saying the rocket equation directly proved that we couldn't possibly build a single-stage rocket that w
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There is no such thing as a "1/100g engine". There might be such thing as an engine which could maintain 1/100g over a specified period of time, with a given total mass and mass-to-fuel ratio. You need all the parts to even be making a sensible statement. It's fine to point out that small constant acceleration can lead to a large change in position/velocity over a long enough timeframe, but that actually has nothing to do with building rocket engines. Clearly we have rocket engines which can sustain acceler
'd be nice if we could wish new physics into being (Score:2)
Yeah, it'd be great if we could just wish new physics into being.
Might as well wish for wormholes or teleportation.
In reality, we need rockets. And chemical rockets actually work just fine. Nuclear-thermal would cost about as much as SLS, and wouldn't even be that useful, it'd just be a nice in-space stage. Reusable launch tech (which we're getting thanks to SpaceX, Blue Origin, Masten Space Systems, and others) gets you cheap launch which makes a nuclear-thermal stage an unnecessary frivolity. Nuclear-ther
There is a plan. But Congress wouldn't like it. (Score:5, Insightful)
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
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No, the space station was a relic of the Apollo era.
Here was the thinking of the time, still high on the success of the Apollo program and dreaming of an even grander future (one in which their budgets didn't get deeply slashed).
1) We'll launch Skylab. It's going to get tons of usage.
2) At the same time, we'll develop a reusable launch system - a Space Shuttle. It's going to get tons and tons of usage and so it'll be very cheap per launch even if annual programme costs are high. And we'll save money beca
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Couldn't agree with you more. :)
Part of NASA's problem is it just has too much infrastructure that it really needs to get rid of that would be way too painful for a government-run agency to just close. So it has to keep all of those people and facilities working on something. They make the goals to suit what they possess rather than the other way around. Sometimes that develops useful things. Sometimes it's just absurdly expensive busywork.
Changing the culture is going to require a combination of a Whi
Maybe, could be, might be, who knows. (Score:2)
Or they might use an improbability machine. Maybe, or an inertialess drive, or maybe -
sigh. another maybe article.
Em Drive (Score:2)
But wait...
Back in 2001 a small satellite propulsion research company was investigating different techniques involving electric engines. That in itself is nothing spectacular. For whatever reason, they developed and tested a closed cavity microwave drive. I do not now the story of why they did such a thin
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Who you calling fictional, Anonymous Cavedweller?
https://en.wikipedia.org/wiki/NERVA.
Sheesh...
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To be fair, NERVA did have problems. Good ISP (~850 sec), but abysmal thrust to weight ratio - depending on what numbers you look at, somewhere between 0,2:1 and 0,5:1 wet, 3-4 dry.
That really puts it as somewhere in-between chemical rockets and VASIMR, which has an even lower thrust to weight ratio but even higher ISP. The thing is... it's sort of an awkward middle ground. If you're going to Mars, you don't need your thrust to be delivered all that quickly. And VASIMR already exists. So unless you can
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You don't need it to be delivered all that quickly, but you do need it to happen within some timeframe. (Important would be that you need to break orbit around the Earth and achieve your orbit to Mars within the same orbit around Earth, or you'll end up having to sped a whole lot more delta-v for the transfer. You can raise the orbit around Earth with a few different burns, so to minimize the delta-v needed for that final burn, but that burn is critical.) If you want to send a ship with a decent mass - l
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VASIMR can provide more than sufficient thrust [phys.org] for a quick Mars journey, so long as you have a good-sized power source to pair to it.
There's no point to a rocket that exhausts its fuel in a few minutes or even hours when you're talking about a journey that even on a fast route will take many weeks to complete.
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but abysmal thrust to weight ratio, depending on what numbers you look at, somewhere between 0,2:1 and 0,5:1 wet
To go to Mars from LEO, you need about a 3600m/s impulse. At an Earth TWR of 0.2:1 (or more properly expressed, an acceleration of ~2m/s^2), you're looking at around a 30 minute burn. Hardly anything unusual. Upper stage boosters routinely use these kinds of accelerations.
Now on to the VASIMR claim. VASIMR exists insofar as a essentially a baby size version of it. Like the VX-200, a 200kW system, capable of, hold on to your seats, a whopping 5N of thrust! Wonderful! Now I'm sure you know of a simple and su
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I'm sorry, but were you under the bizarre impression that anyone in this thread was saying that the burn time on NERVA would be too long to be useful? And if so, why?
And with the 620kg full system mass, plus 170kg propellant at 5000 ISP, the system could accelerate a 1605kg payload t
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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 f
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Has it ever been used to push any mass whatsoever in space? No? It's fictional.
Following your definition, you're either fictional or surprisingly resistant to radiation, void, combustion and, presumably, landing at high speeds.
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Yeah, because nuclear thermal propulsion is SOOO science fiction and entirely impossible. No wait, it's just using a big box of heat to turn a liquid into an expanding gas, which you then eject out of a rocket nozzle. This, of course, has the advantage of rather simple, and massively cutting down the weight of what you're taking with you, because you're not bringing along several tons of chemical oxidizer so that you can use your traditional rocket for something besides mass. And it was already prototype
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Re:NOT EVEN POSSIBLE!!! (Score:5, Insightful)
Wow...
To think that your vote counts as much as normal people's...
Re:NOT EVEN POSSIBLE!!! (Score:4, Informative)
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.
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There's a little bit of a difference between thermal decay generators and nuclear propulsion. All deep space probes have an RTG, solar panels don't work when you're far from the sun. Even with the RTGs there's been concern about what to do if there's a launch accident. But direct nuclear propulsion is inherently dirty--in Project Pluto it was actually considered a feature that in addition to dropping nukes the platform could just be flown around irradiating the target. AFAIK nuclear propulsion is only envis
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There's a little bit of a difference between thermal decay generators and nuclear propulsion.
RTG's are not the only nuclear power sources -- look up RORSAT and the BES-5 reactor.
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You do realize that there have been RTGs that reentered, and even ones involved in launch accidents where the rockets broke up explosively. You know what happened? They bounced.
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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!!
Re:NOT EVEN POSSIBLE!!! (Score:5, Informative)
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.
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False.
Go away.
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What always made me wonder about that in the book and movie was why he didn't use the RTG to also charge the batteries. It wasn't big enough to power the rover, but would have provided a good amount of baseload power for the rover.
Yes, boys and girls. . . . (Score:3)
While the Outer Space Treaty of 1967 [nasa.gov] 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 [wikipedia.org]. Even so, calling the bombs in question "impulse devices" would technically make them allowable under the Outer Space Treaty. .
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>> 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)."
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Then you drop in a small crew of people
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I can't wait to see the development budget on the world's first "no maintenance extraterrestrial stripmining robot fleet". Given that probes like Curiosity that slowly roll around making observations cost billions of USD.
And the budget for the prep missions that would be required to gather the data needed in the development of such robots.
Also: don't get your hopes up for Mars farms on early missions. Seriously. Farms that provide relevant food outputs to keep people alive are big even on Earth. Light i
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Don't get your hopes up for gardens ;) Don't get me wrong, the first mission will surely involve plants. But they'll be more along the lines of something with a cutsie acronym like MAPLE (MArs PLant Experiment) or the like. It'll be a little self-contained box the size of a beach ball with its own self-contained grow environment that raises enough lettuce for a salad or two and the occasional sprig of basil. And NASA will make sure to get about 50 press releases out of it.
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Nuclear would be much more feasible, no worries about long term health effects and less shielding, weight, propellant, and costs.
I would speculate that airing nuclear propulsion is precisely a way to get assistance with costs. If there is a tiny chance that it can have future military application, funding is much easier to attain. If nuclear space propulsion makes it easier or quicker to launch missiles at a future Chinese moon/Mars/Mercury base or even launch a missile from space towards an Earth target, it buys the votes of the large group of Jingoists in congress.
Things like finding out how rocks formed so we can know more about
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They built and tested at least one nuclear rocket design in the 1960s.
High ISP but heavy. Useless for an ICBM.
Play some KSP, you'll understand.
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Useless for an ICBM.
I don't think anyone has suggested ICBM. IPBM, on the other hand....
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As we still don't know how it works, no one knows how to scale it up to use it to push something big. Currently it doesn't have enough force for something the size of a snowblower to push a pencil across the desk.
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