Only one US-built nuclear reactor has ever flown in space, and that was more than 60 years ago.
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Here is NASA’s plan for nuking Gateway and sending it to Mars
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Sigh. I guess we should be glad it's not SR-1 Mars Atomic Gateway Aquisition.
Kudos to Isaacman for continiung to read the current administration so well.
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It's pointed out in the article, basically all parts are paid for already.
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The part that feels like flag planting is that they are tightly limiting the mission to actually achieve something. That’s a welcome change from bigger programs that are permanently 10 years away from flying.
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Once it drops copters on Mars, it's going to head back to Earth for next load.
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Anyone have this on their bingo card? I figured the Lunar Gateway might end up as a comms satellite in NRHO, maybe doubling as an emergency refuge for astronauts.
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I think the reason they're doing it is to buy it more insurance against being axed by congress (how does that old saying go, 'no Buck Rogers, no bucks'?).
If thats the case, I couldn't give less of a damn about what they choose to call it.
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HEU (Highly Enriched Uranium) isn’t very toxic and is not very radioactive. Which is why you see technicians handling fuel rods for such reactors with gloves and masks.
Until the reactor is run, of course.
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It's not a US-exclusive phenomenon, try translating some Russian or Chinese spacecraft names. For example, 'Soyuz' means 'Union' and 'Tiangong' means 'Heavenly Palace'.
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Issacman continues to be a bright spot among a pool of very dim leadership in this administration. I'm hopeful that he's able to pin enough NASA missions to administration priorities that he doesn't fall into the "Defund NASA" trap again next year.
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Freedom has been NASA's placeholder name for a space station since the replacement for Skylab was mooted in the 80s. I'm not sure what it's doing attached to a NEP demo, though.
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"No bucks, no Buck Rogers" is the line from "The Right Stuff". But yes I assume that is definitely the intent.
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For those curious, "Only one US-built nuclear reactor has ever flown in space, and that was more than 60 years ago" was apparently the SNAP-10A mission in 1965: https://en.wikipedia.org/wiki/SNAP-10A
I was thinking, surely the Voyager missions launched in the 70s used nuclear power as well, given their long lifespan remote from the sun? Wikipedia tells me Voyager 1 and 2 (and many others) use a "radioisotope thermoelectric generator (RTG)" which uses plutonium-238 to generate heat for electricity. Sounds a lot like what I'd call a nuclear reactor, but I guess the latter uses a chain reaction while the former "just" relies on elements to decay and is therefore more like a battery.
(edit, not exactly related to the article, but apparently Voyager 1, which is the furthest man-made thing from Earth, will reach a distance of one light day from Earth in November this year. What a great "day" to celebrate!)
I was thinking, surely the Voyager missions launched in the 70s used nuclear power as well, given their long lifespan remote from the sun? Wikipedia tells me Voyager 1 and 2 (and many others) use a "radioisotope thermoelectric generator (RTG)" which uses plutonium-238 to generate heat for electricity. Sounds a lot like what I'd call a nuclear reactor, but I guess the latter uses a chain reaction while the former "just" relies on elements to decay and is therefore more like a battery.
(edit, not exactly related to the article, but apparently Voyager 1, which is the furthest man-made thing from Earth, will reach a distance of one light day from Earth in November this year. What a great "day" to celebrate!)
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I was hoping they would cancel Gateway, then do a Ship of Theseus thing with it and ISS, but this is a very happy surprise.
Maybe they can dust off some old satellite and strap it on. What about those telescope assemblies that the NRO gave NASA? Is there utility to having one go to Mars? Or even better, to sending it out past Mars, once it drops its kids off?
Maybe they can dust off some old satellite and strap it on. What about those telescope assemblies that the NRO gave NASA? Is there utility to having one go to Mars? Or even better, to sending it out past Mars, once it drops its kids off?
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This seems like a solid R&D mission. Not sure how you get flag planting, there's nothing here that hasn't been done before in terms of going to Mars, or flying a drone there.
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RTGs have also been used for other NASA Deep Space missions such as New Horizons and Galileo because past the orbit of Jupiter, solar power becomes uneconomical as a way to power space probes (the solar panels that power the Juno probe in orbit around Jupiter are massive to compensate for the weaker concentration of solar radiation that reaches out to Jupiter's orbit). RTGs have also been used to power the Mars rovers Curiosity and Perseverance, as previously NASA had mixed results using solar power on the dusty surface of Mars.
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That's exactly how an RTG works. The natural decay of the radioactive source generates heat, with associated thermocouples generating electricity.
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Technically, all nuclear reactors ever placed into space (mostly Soviet designs) have also used systems identical to those or like those employed on RTGs to convert thermal energy into electricity.
This means that, while they still generate a lot more thermal energy per given kilogram of fuel (their chain reactions allowing for such over simple decay), you still have very poor conversion of said energy into electricity.
Obtaining greater efficiency requires the use of more mechanically complex and thus more expensive alternatives. While boiling water into steam to spin turbines is the most common means of generating electricity from nuclear reactors on Earth, they have properties that make them too heavy and complex for use in space where non-payload and non-propellant masses have a more deleterious effect than they do compared to more terrestrial forms of propulsion.
Instead, it's generally preferred to use a number of alternative engines (or cycles) that employ gas as a working medium in lieu of water.
Coincidentally, such cycles can use a variety of energy sources, including decaying radioisotopes, nuclear reactors, and even concentrated Sunlight. Stirling engines (among others) have in fact been seriously investigated as a way to generate more electricity per given amount of Plutonium-238 than is obtained with extant RTGs.
While there has been a lot of work done on nuclear power systems for space applications in recent years, completing even the most barebones nuclear vehicle in two years is astronomically unlikely under any condition. I also doubt that the White House is going to request a realistic budget for such a mission, let alone get that budget approved by Congress.
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Europe should take their module and components back. Screw the unreliable americans.
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Curiosity and Perseverance are nuclear because of how power-hungry they are. Solar arrays large enough for them would obstruct their vision and be difficult to manage on uneven terrain.
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Given the details from that slide (*), it's almost certainly Westinghouse's eVinci-derived design, i.e. heat pipes, HALEU, Brayton cycle engine. With some sarcasm, Kilopower seems to exist so that people can say that nuclear power in space cannot work because not enough power per mass, not enough power, limitations of Stirling engines etc. eVinci reactor has far more scope for cranking up the wattage, considering it's positioned as "nuclear battery" for remote mining installations.
I'm not sure where the "mostly built" part comes from, here's Westinghouse's recent xeet about test facility they built to test their fancy extra long heat pipes, so they're definitely working on it, but you'd think they'd be advertising it if they had actually made solid progress on the space version. Possibly it refers to the progress on the DOME demonstrator, which is much larger than indicated here, though.
View: https://x.com/WECNuclear/status/2031482293726949569
(*) So that's where it came from, the earlier article had someone in comments saying it was in Nasa X, which it isn't, but it is in fact from Nasa's material.
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eVinci is designed to run 8 years on full blast before it needs refuelling, so presumably that's not a limiting item unless Nasa plans to take it on a tour over the Solar system.. Unlikely it'd carry enough reaction mass for the hall-effect thrusters to go to, say, Saturn, though.
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