Here is NASA’s plan for nuking Gateway and sending it to Mars

Only one US-built nuclear reactor has ever flown in space, and that was more than 60 years ago.

See full article...

 

[SinclairZX81]

... IMHO, let's avoid massive scope creep, but it would be really cool if it doesn't add to scheduling concerns or massively to cost, frankly slap a small number of science packages to it and aim it at Uranus or Neptune and put it in orbit around one of them after Mars....

That's why it's called "scope-creep." One little change begets another, which begets another. If you don't have absolute engineering discipline about the goals and limits of what you're trying to do here, pretty soon you're doubling your budget and tripling the timeframe.

Science package design could easily consume the entire two years before this is ready to launch, let alone building and testing them, And then they can have their very own scope-creep, which has deep-sixed more than one such project.

This is a tech demo, a la Deep Space 1.which proved out the deep-space ion propulsion that has become almost commonplace now. In-scope, we're getting 3 (or six) new helicopters on Mars, and a proof-of-concept NEP propulsion system demonstration. It's plenty.

Keep to the plan, make the deadline.

 

[Oldmanalex]

It's pointed out in the article, basically all parts are paid for already.

If that were true, there would be little opportunity for grift, and no administration support.

 

[lasertekk]

A high power engine exists in VASIMR. They just need a 250kW flight certified power source to power it. It’s being developed by former NASA astronaut Dr. Diaz-Chang.

ad Astra Variable Specific Impulse Magnetoplasma Rocket

Yep. The engine works. It's a pretty mature design by now. They've test fired it for many dozens of hours continuously, on many separate occassions. It just needs a power supply.

 

[SinclairZX81]

Isn’t that the sort of the mentality that got us the SLS though? I mean, it’s different because a lot of components are already very mostly built in this case but there’s a non trivial integration of the various systems to a functional space craft remaining, no? Even then, there’s a lot riding on the “all components are mostly built” being thrown about in the comments. Is mostly built 99.5% and only final adjustments remain? Or is it the “the final 10% of construction takes 90% of the time” situation?

Close. It's "the first 90% of the project takes 90% of the project schedule, and the last 10% of the project takes the next 90% of the project schedule." Yes, the math is bogus. When you've been involved in one of those, you know that it's exactly how it works.

And without everything going just right and a heck of a lot of engineering and management discipline, that could easily happen here, yes.

 

[dmsullivan2]

you want them to call it Trumpship one?

Mars-a-Lago

 

[DancesWithBikers]

So it's an interplanetary nuclear powered aircraft carrier? Rad!

Thumbs up for "rad".

 

[Bill Swallow]

It will be called Freedom Station because a certain kind of apparatchik comes standard with very limited imagination.

I mean, they could try Diana Station as a wry acknowledgement of the Artemis project, but I suspect the name sounds too female for the fake machos making the decisions.

(P.S.: Please, no-one tell Rump who Artemis is.)

You mean Gordon? He was James West's sidekick! ;-)

 

[Bill Swallow]

Close. It's "the first 90% of the project takes 90% of the project schedule, and the last 10% of the project takes the next 90% of the project schedule." Yes, the math is bogus. When you've been involved in one of those, you know that it's exactly how it works.

And without everything going just right and a heck of a lot of engineering and management discipline, that could easily happen here, yes.

Schedules are like TARDISes (TARDII?). They contain far more time on the inside than is visible looking at them from the outside.

 

[brionl]

Who says it's flagship cost? Okay, it uses the PPE from gateway, which is no doubt hideously expensive like everything else SLS-adjacent, but that's already spent money.

And the probe is the mission, like Isaacman says, the fission reactor coupled with Ion engine is the hard part and they don't want mission creep to balloon schedules and cost out of hand like always. Invading Mars with aerial drones dropship-style is just a bonus. Having said that, the nuclear reactor should let you run nice powerful comms array, which shouldn't take 5 billion and 20 years to develop.

We just had an article recently about a developing a Mars orbiting relay mission, that was supposed to also be launched for the '28 window. Might be worthwhile considering bolting it alongside this one too.

 

[zunipus]

This article is AVOIDING the biggest problem with sending a nuclear reactor up in a rocket. I consider it a shameful omission. And it's obvious:
-> If the rocket and/or the reactor blows up in Earth's atmosphere, what happens? Here's a useful reference:
"What Happens Inside an Exploding Nuclear Reactor?"
https://www.watchmojo.com/articles/what-happens-inside-an-exploding-nuclear-reactor-unveiled

 

[nomoroto]

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.

RTGs were also flown on every Apollo mission after Apollo 11 to power the ALSEP instruments on the lunar surface.

https://airandspace.si.edu/collection-objects/assembly-fuel-case-apollo/nasm_A19750027000

Something most people didn't hear about was that, on the Apollo 13 mission, the RTG was still on the LM "life boat" and presumably burned up during re-entry.

(edit) Upon further reading apparently the A13 RTG may have survived re-entry, and A13 was not the first time an RTG re-entered the Earth's atmosphere.

https://www.spacesafetymagazine.com...ion/will-anyone-recover-apollo-13s-plutonium/

 

[Argent Claim]

The whole point of this is that for decades, we have had a cycle of

• design nuclear propulsion
• the mission grows to unaffordable
• cancelled
• design nuclear propulsion

….

By flying a mission, you break that cycle.

As part of that, you need to pare down what it is demonstrating to the implementable

The reason nuclear powered missions have not really taken off is because they have an invariably high price tag. Even if you had a thoroughly tested, modular, universal nuclear electric rocket design simply lying around, you're still left with a very complicated and very expensive system that's not cost competitive in many circumstances or even all that useful for many applications.

In fact, I would argue that adding nuclear power would ultimately encourage higher mission costs in the long run via the same feature creep being criticized here. After all, what is the point of having superior payload and electrical output capacities if you aren't going to use them?

There simply is no, "cycle" here that's going to be broken unless NASA gets a significant budget increase that can absorb the greater additional costs of nuclear power beyond a mere test article.

However, as it is, there remains a very significant possibility this thing never makes it into orbit. Budgeting for a mere two years of development means that any delay will have significant cost growth attached. Generously assuming this make it past Congress, it could just as easily be canceled two years from now, especially if it's discovered that the whatever budget the White House proposes has no basis in reality (which is more common than not).

I know a lot of people want this to be a thing, but there is very little reason to take any of this seriously and even less to get excited about. It's more likely than not to simply be added to the enormous mountain of aborted proposals like Nautilus-X, Ares I and ARM.

 

[Malmesbury]

The reason nuclear powered missions have not really taken off is because they have an invariably high price tag. Even if you had a thoroughly tested, modular, universal nuclear electric rocket design simply lying around, you're still left with a very complicated and very expensive system that's not cost competitive in many circumstances or even all that useful for many applications.

In fact, I would argue that adding nuclear power would ultimately encourage higher mission costs in the long run via the same feature creep being criticized here. After all, what is the point of having superior payload and electrical output capacities if you aren't going to use them?

There simply is no, "cycle" here that's going to be broken unless NASA gets a significant budget increase that can absorb the greater additional costs of nuclear power beyond a mere test article.

However, as it is, there remains a very significant possibility this thing never makes it into orbit. Budgeting for a mere two years of development means that any delay will have significant cost growth attached. Generously assuming this make it past Congress, it could just as easily be canceled two years from now, especially if it's discovered that the whatever budget the White House proposes has no basis in reality (which is more common than not).

I know a lot of people want this to be a thing, but there is very little reason to take any of this seriously and even less to get excited about. It's more likely than not to simply be added to the enormous mountain of aborted proposals like Nautilus-X, Ares I and ARM.

The reason that the proposals have all got insanely expensive is something we have seen in this thread - "But while you are doing this, we need to add this extra thing, otherwise the mission is a waste."

What nuclear electric propulsion needs is a demo, a baseline of what works now.

Not an X-33 style every-exotic-tech-we-can-find, nor a battleship spacecraft carrier with everything including a spare JWST bolted to it.

Something closer to SNAP-10 connected to xenon thrusters.

Sure, people will decry this as boring. But it has a better chance of making it to the launch pad.

 

[Walker On Earth]

However, as it is, there remains a very significant possibility this thing never makes it into orbit. Budgeting for a mere two years of development means that any delay will have significant cost growth attached. Generously assuming this make it past Congress, it could just as easily be canceled two years from now, especially if it's discovered that the whatever budget the White House proposes has no basis in reality (which is more common than not).

I know a lot of people want this to be a thing, but there is very little reason to take any of this seriously and even less to get excited about. It's more likely than not to simply be added to the enormous mountain of aborted proposals like Nautilus-X, Ares I and ARM.

I very much want this to be a thing; I've been hoping for a nuclear rocket Real Soon Now ever since Miss Pickerell Goes to Mars. But yes there is really not a lot to be excited about here even if this project delivers as promised simply because the higher Isp won't be used to get anywhere faster, it'll be used to deliver larger payloads ... precisely the opposite of what most people here are hoping for.

 

[Argent Claim]

The reason that the proposals have all got insanely expensive is something we have seen in this thread - "But while you are doing this, we need to add this extra thing, otherwise the mission is a waste."

Historic proposals for nuclear energy in space never got far enough for feature creep to be an issue in the first place. Even Project Prometheus didn't get that far.

They were canceled because nuclear energy related to anything is simply and invariably more expensive and (in many contexts) increasingly less competitive compared to alternatives.

DRACO, for instance, was specifically planned as producing nothing more than a barebones demo at the program's end. Yet it too was canceled because the costs needed to build up to that test and then construct mission-ready successors was simply too high to justify.

What nuclear electric propulsion needs is a demo, a baseline of what works now.

NASA doesn't require a demo: NASA requires money to justify its use afterwards. A one and done demonstration is pointless if you can't ever afford to build upon it.

Not an X-33 style every-exotic-tech-we-can-find, nor a battleship spacecraft carrier with everything including a spare JWST bolted to it.

Again: If you can't fund the subsequent expensive missions that justify the advantages of expensive nuclear electric propulsion systems, then there really isn't any point in starting. You're simply throwing money down a hole at that point that could be used on programs that will produce tangible results.

Something closer to SNAP-10 connected to xenon thrusters.

SNAP-10A failed after just over a month in orbit with significant propulsion issues before that despite having spent a whole decade in development. What is being proposed here is significantly more complicated with many more opportunities for failure, and there is simply not a real chance that it is going to be completed in two years however barebones the final product is. Nuclear energy is, again, expensive and difficult. Hence why we haven't really seen it take off despite there being multiple programs laser focused on nuclear systems alone.

Sure, people will decry this as boring. But it has a better chance of making it to the launch pad.

At no point in anything that I have written did I criticize the proposal for being boring, nor do I think anyone would level such criticism against it.

My own point has consistently been that it there is little justification for this particular venture if it comes at the expense of planetary science (the only reason to even entertain nuclear electric propulsion) and that it is being campaigned on an absurdly unrealistic timeline with all the inevtable cost overruns that failing to meet said timeline will entail.

 

[Hydrargyrum]

Send that large probe to psyche, with a nuclear power source it can just cut the raw iron nickel into rods and melt the outer surface layer, and have reasonably strong high quality iron nickel alloy. Pysches gravity is low enough, about 1.3% of earth, you can just push off into orbit with an arm getting you height and a tiny burn. It sounds perfect for moving around and getting big 100 kilogram samples from low gravity moons and large asteroids, starting at Mars and then moving to psyche, and then bringing back samples to drop off at earth or the moon base.

That does sound like a cool project, but would be better suited for the second generation after this tech demo. A complex payload like that and a new power source on the same mission is a lot of technical risk and development scope to take on all at once - there’s a high chance it would end up like JWST in terms of budget and schedule performance.

 

[InvariantCapitalist]

This article is AVOIDING the biggest problem with sending a nuclear reactor up in a rocket. I consider it a shameful omission. And it's obvious:
-> If the rocket and/or the reactor blows up in Earth's atmosphere, what happens? Here's a useful reference:
"What Happens Inside an Exploding Nuclear Reactor?"
https://www.watchmojo.com/articles/what-happens-inside-an-exploding-nuclear-reactor-unveiled

I love WatchMojo when they break down the best synth pop videos of the early 80s and where are they now!

But I wouldn't use them for a source on nuclear energy risks. Especially when they aren't talking about space based reactors, which have almost zero radiation risk during launch given they aren't ever activated until they reach orbit. Uranium is heavy and not that dangerous, until you use it in a nuclear reaction.

 

[seansd]

Please get a science literate proof reader, its embarrassing.

 

[InvariantCapitalist]

So my math on NEP is that claims are ISP of 6,000 to 10,000, and thrust levels of 10 to 100 newtons. Assuming a probe is built that can store enough propellent to be 80% of mass, the raw math spits out something like 95 km/sec of deltaV, giving 2-3 years of acceleration.

Obviously that's hella impressive. That's Jupiter within months and Pluto in a couple years. Its less than a couple years to go to Neptune AND slow down to stay in orbit for long term measurements and imaging. Or its catching up to 3/I Atlas within a few years to observe it from close range.

But the part I can't figure out is, are those thrust levels realistic with the reactors they are talking about, and does the reactor have enough energy density to turn all that propellent into grunt? Lastly, what kind of propellent are we talking about and how easy to store and does 80% of mass even make sense?

 

[InvariantCapitalist]

I very much want this to be a thing; I've been hoping for a nuclear rocket Real Soon Now ever since Miss Pickerell Goes to Mars. But yes there is really not a lot to be excited about here even if this project delivers as promised simply because the higher Isp won't be used to get anywhere faster, it'll be used to deliver larger payloads ... precisely the opposite of what most people here are hoping for.

Its impossible to get anywhere faster with an NEP, unless NEPs are first built.