Nuke the Moon!

[aerostadt]

Fusion is not the cure-all that most people think it is. The 4 proton reaction (or 4 hydrogen atoms going to helium) has an effective ignition temperature way too high to be achieved by current technology. The deuturium-tritium reaction is one of the easiest to achieve, but it can create a 17 MEV neutron. Hardly, a case of radiation-free nuclear power.

I am amazed at how these discussions that start out on one subject digress into solving the world's problems. Why not start another thread on solving the problems of over-population, protecting the environment, etc. Why should we even consider launching model rockets when so many world problems need to be solved?

 

[BABAR]

Okay, here’s one for @jqavins and @prfesser and the other brainiacs.

would steam power work on the moon?

it would only work during the two week daytime.

dig a fairly deep (say 10-20 meter) hole with a big sealed cavern. Daytime surface temps are up to 127 degrees Celsius. Boiler on surface, but underground should be much less, since night surface temps are minus 173 C.

boiler on surface, run through steam generator and vent to cavern, water condenses on the deep side and is recycled/pumped to surface boiler.

apparently there IS some water on the moon, so the resource is already there. Still doesn’t solve the night time problem, and not sure of steam power efficiency compared to direct solar conversion. Nice to have options.

 

[BABAR]

Why should we even consider launching model rockets when so many world problems need to be solved?

Because it’s fun?

 

[aerostadt]

Okay, here’s one for @jqavins and @prfesser and the other brainiacs.

would stream power work on the moon?

it would only work during the two week daytime.

dig a fairly deep (say 10-20 meter) hole with a big sealed cavern. Daytime surface temps are up to 127 degrees Celsius. Boiler on surface, but underground should be much less, since night surface temps are minus 173 C.

boiler on surface, run through steam generator and vent to cavern, water condenses on the deep side and is recycled/pumped to surface boiler.

apparently there IS some water on the moon, so the resource is already there. Still doesn’t solve the night time problem, and not sure of steam power efficiency compared to direct solar conversion. Nice to have options.

I think something like this would work. Someone mentioned something like this on an earlier post talking about the 2weeks of daylight and 2 weeks of nighttime. Temperatures are over 200 Deg.F. during the day and about 200 Deg.F below zero at night. Probably, some kind of fluid could be pumped through a surface network during the day and then stored and, likewise some kind of fluid could be pumped through a surface network at night and stored all for a whopping total of 400 Deg.F differential temperature. There is speculation that there are very large lava tubes on the Moon. Such a place might be ideal for this kind of concept. However, such a project is a larger engineering project than is what is available now. Lifting moon exploration by the bootstraps with readily available power is needed. This is where a nuclear power source can be handy.

BTW a nuclear power source for making methane and oxygen on Mars does not need the Stirling cycle. It just needs to provide a heat source.

 

[cbwho]

The most surprising aspect of this discussion that even those involved in rocketry are luddites.

 

[prfesser]

Okay, here’s one for @jqavins and @prfesser and the other brainiacs.

would stream power work on the moon?

it would only work during the two week daytime.

dig a fairly deep (say 10-20 meter) hole with a big sealed cavern. Daytime surface temps are up to 127 degrees Celsius. Boiler on surface, but underground should be much less, since night surface temps are minus 173 C.

boiler on surface, run through steam generator and vent to cavern, water condenses on the deep side and is recycled/pumped to surface boiler.

apparently there IS some water on the moon, so the resource is already there. Still doesn’t solve the night time problem, and not sure of steam power efficiency compared to direct solar conversion. Nice to have options.

You need a good engineer to answer that, because they do math and I don't.

Off the cuff, I'd suggest that a temperature differential of 27C (boiling point vs. surface temp) might be too low to work for steam generation. A larger difference may be needed for efficient, rapid steam generation.

However...a thermocouple arrangement, with one junction at 127C and the other at -173C, might be feasible. I know there have been models of ocean systems like this, where one junction is down deep near freezing, and the other is in desert sun. "How big does such an arrangement need to be?" is a question I can't answer. Massive energy storage would be needed for nighttime.

Best -- Terry

 

[BABAR]

You need a good engineer to answer that, because they do math and I don't.

Off the cuff, I'd suggest that a temperature differential of 27C (boiling point vs. surface temp) might be too low to work for steam generation. A larger difference may be needed for efficient, rapid steam generation.

However...a thermocouple arrangement, with one junction at 127C and the other at -173C, might be feasible. I know there have been models of ocean systems like this, where one junction is down deep near freezing, and the other is in desert sun. "How big does such an arrangement need to be?" is a question I can't answer. Massive energy storage would be needed for nighttime.

Best -- Terry

Perhaps I am one of @cbwho ’s Luddites (.). I was thinking that just by digging down 10-20 meters the underground temperature may approach 0 degrees centigrade. Since the moon rotates (albeit slowly) with surface temperatures swinging from plus 127 C to minus 173, I am not sure how deep you’d need to go to hit a level where the temeperature is relatively constant.

Earth temperature worldwide is relatively constant at 50-60 degrees F, the concept that allows geothermal heat pumps to work. Geothermal GENERATORS work the opposite way, tapping into subterranean heat sources to generate power from atypical at or near surface hot pockets, sort of like natural hot springs, geysers, preferably not volcanoes.

https://www.architectmagazine.com/technology/going-underground_o
depending on the depth you’d need to dig to reach 0 degrees Celsius (may not even have to get that low with surface temps of 127 Celsius, and the SIZE of the cavern required for gas expansion, seems like geothermal GENERATORS would be possible. Not sure if these would be more EFFICIENT than solar, but IF we can find sufficient water on the moon, and SINCE I believe the moon has significant resources of iron, titanium, and aluminum, the materials are ALREADY there. Interestingly, the aluminum refining process yields byproducts of oxygen, obviously of use, and silicon which could be used to make solar panels.

https://lunarpedia.org/w/Lunar_Aluminum_Production
so the key factor may be water, although once found, I am not sure if we could approach 100% efficiency in recycling the water used.

 

[aerostadt]

Just bury a tank within a concentric tank with a slightly larger diameter and connect the space in-between to the surface where there is a vacuum and lo and behold you have a thermos bottle.

 

[ksaves2]

NASA's baseline design for a reactor such as this is a liquid sodium reactor which requires no water. See NASA Mars Reference Architecture for an explanation. I am assuming NASA wants to use a liquid sodium reactor on the moon as a proof of concept for Mars.

There is no way a RTG would be able to put out these power levels.

I thought sodium metal is hard to work with. I remember cutting a small piece of shiny metal sodium in organic chemistry lab from a "large wad" (stored under oil") and tossed it into a wet sink.
The "glob" danced around, flared and the hydrogen gas elicited exploded or popped if one is so inclined. Everyone laughed and thank heavens the professor wasn't nearby.

I'm aware that liquid metal sodium was used to cool reactors but thought that must have been hard to do!

Kurt

 

[rharshberger]

I thought sodium metal is hard to work with. I remember cutting a small piece of shiny metal sodium in organic chemistry lab from a "large wad" (stored under oil") and tossed it into a wet sink.
The "glob" danced around, flared and the hydrogen gas elicited exploded or popped if one is so inclined. Everyone laughed and thank heavens the professor wasn't nearby.

The Soviet sodium cooled submarine reactors required a heat source to keep the coolant liquid when the subs reactors were shut down for maintenance.

I'm aware that liquid metal sodium was used to cool reactors but thought that must have been hard to do!

Kurt

Most sodium cooled reactors use a sodium alloy, for example iirc the Fast Flux Test Facility according to sources I have read uses a sodium-potassium eutectic alloy that is liquid at room temp. afaik when they drained the 600 gallons of coolant from the FFTF no special thermal requirements were needed, and the core was backfilled with argon to prevent corrosion if they decide to put it back in service someday (not likely with todays government) of course its one of only a few reactors capable of producing medical grade Technicium-99.

 

[aerostadt]

Commercial fast breeder reactors are against the law in the US since the days of Jimmy Carter. It is against the law to even extract plutonium from spent fuel rods from light water reactors to be used in commercial reactors.

 

[rharshberger]

Commercial fast breeder reactors are against the law in the US since the days of Jimmy Carter. It is against the law to even extract plutonium from spent fuel rods from light water reactors to be used in commercial reactors.

Well....sort of the the FFTF (fast flux test facility) is indeed a breeder reactor its also a test reactor, if they were outlawed in the US since Jimmy Carter then the FFTF must be in some other category as it first went active in 1982 and was shutdown in 1992 all other US breeders were built in the 60's and all US breeders were offline by 1994. The main reason nuclear power of any variety is fewer in the US is due to the political climate, yes they produce a very long lived waste, but they are pretty carbon neutral overall and produce a huge amount of power for the amount of fuel expended. I work near the FFTF facility which is currently mothballed (probably never to be reactivated), and a commercial BWR reactor (less than 10 miles from FFTF) the commercial reactor Columbia Generating Station was commissioned in 1984 and has run continously with zero incidents for 36 years, every bit of used fuel is stored on site in shielded casks above ground (satellite observable) each about 10' in diameter awaiting the day the US decides to reprocess the used fuel, the issue with reprocessing the fuel is that up to 1% is PU-239, and another less than 1% is fissile U-235, about 96% of the used fuel can be reprocessed into usable fuel. Its the 2% fissle materials that are the main reasons we dont reprocess fuel here in the US (India, France, and the UK are the only countries I know of that do/did), our reason are for non-proliferation (no new weapons grade fissiles) reasons.

Just my two cents, personally I prefer nuclear to wind power. The Columbia Generating Station produces 1216 MW of power, the Alta Wind Energy Complex in California uses 600 turbines to produce 1550 MW, I would much rather see a single steam cloud than 600 turbines creating visual pollution (my term). We have hundreds of turbines visible from my home and they are ugly and unless the energy demand is high most are not even turning.

 

[Grog6]

Power on the moon is easy; solar can feed most industrial processes; a deep crater with ice+gasses makes the cold end.
Make a focussed sunlight furnace and you can process regolith into metals, and reclaim oxygen and other gasses from the mix in the process.
You can seperate chemicals by ionizing them, running them across a magnet to do mass separation, and the atomically fine powder can be melted into metal.
This is part of a "universal maker" something that featured regularly in sci fi since the 30's.Hogan's code of the lifemaker is a fun take on it.

 

[georgegassaway]

In the Apple TV show "For All Mankind", Jamestown base has a nuclear reactor that is the primary power for the base (and presumably the primary power to break down the ice into oxygen & hydrogen & chill it to be useable fuel for their reusable landers). Of course, that's a TV show, but the viewing public wasn't up in arms "how dare the US have a nuclear reactor on the moon in the show!" I was incredibly PO'ed with the show's writers at what they did to turn season 2 into "Space War 84", rather than the what the title of the freaking show is supposed to mean, and the consequences.

 

[aerostadt]

Essentially, the hopes for large scale commercial breeder reactors were killed in 1983 when Congress voted to end the Clinch River Breeder reactor, a 1000 Mw thermal reactor (350 megawatts electrical).
https://en.wikipedia.org/wiki/Clinch_River_Breeder_Reactor_Project

 

[aerostadt]

There are several common gases that liquefy above the -173 C mentioned in a earlier post for the moon's night side, such as ethane(-88.78 C), ethylene(-103.7 C), carbon dioxide(-78.7 C), and methane(-161.5 C). These gases will easily vaporize in the 100 C temperature on the moon's day side. Pulling such a working fluid through a turbine (Brayton cycle) can make electricity. The temperature differential on a commercial light water reactor is only on the order of 550 Deg.F. The hot water coming out of the core is about 600 Deg.F. and creates steam through a heat exchanger at about the same temperature. Dumping this waste heat to the environment (about 50 Deg.F) gives a working temperature differential of about 550 Deg.F.

 

[Grog6]

Even if steam won't work, some gas/liquid/solid will work, be it water, steam, acetone, ammonia, helium, whatever; it can support a steam-like engine.
I've seen a helium compressor that ran on the difference between liquid helium and nitrogen.
No one really wanted Plutonium reprocessing due to the ease of diversion, and the small critical mass of Pu239.

 

[aerostadt]

No one really wanted Plutonium reprocessing due to the ease of diversion, and the small critical mass of Pu239.

That is the biggest drawback. However, as I recall the French were reprocessing spent fuel rods for themselves and the Japanese for fissionable material. I am assuming that they are still doing it. I am assuming that they can retrieve the plutonium.

One could say that it is illegal to "burn" plutonium in a commercial light water reactor. However, as I recall there was an article in Scientific American years ago that pointed out that a small amount of plutonium is generated in U.S. commercial light water reactors and a certain amount is then actually consumed to make electricity. Is this a violation? No one seems to mind. IMHO this is just as well because it is reducing the amount of free plutonium available.

More is available on Google
https://en.wikipedia.org/wiki/La_Hague_site

 

[Grog6]

There are reactors burning "Mox" or mixed oxide fuels. That's Plutonium and uranium oxide.
That's the only way we can legally use the Plutonium we bought from Russia under the Sapphire Project.

 

[aerostadt]

There are reactors burning "Mox" or mixed oxide fuels. That's Plutonium and uranium oxide.
That's the only way we can legally use the Plutonium we bought from Russia under the Sapphire Project.

It is my understanding that France is using MOX and perhaps other foreign countries. From skimming the internet it is not clear that MOX is being used in the U.S. There was a letter issued by the NRC to use MOX in the Catawba (Duke Power) light water reactor in 2005. There was a MOX reprocessing plant that was cancelled in North Carolina in 2018.
https://world-nuclear-news.org/Articles/US-MOX-facility-contract-terminated

 

[Grog6]

I guess we;ll have to repurpose all that weapons grade plutonium, lol.

 

[aerostadt]

We have until Feb. 19 to submit our plan for a lunar nuclear reactor. Sounds like just a proposal for now.
https://www.orlandosentinel.com/spa...0211129-o235fkbqojcq7eb6e3euw5o23u-story.html

 

[aerostadt]

China is working on a nuclear lunar power plant.
https://thehill.com/opinion/technology/584232-the-nasa-china-space-race-is-about-to-go-nuclear

 

[boomtube-mk2]

I remember reading once that if a space vehicle had 1-G of acceleration available to it, that Mars is three days away.
Jupiter would take three weeks.

NERVA might have given us that capability had we fully developed it.

 

[OverTheTop]

I remember reading once that if a space vehicle had 1-G of acceleration available to it, that Mars is three days away.
Jupiter would take three weeks.

NERVA might have given us that capability had we fully developed it.

There is certainly promise there. There are much better contemporary versions of NERVA and there was even one tested only a couple of years back. Lofting the nuclear thermal engine is a low-risk manouver, contrary to popular belief. The reactor has not been fired up at that time so even in the event of a failed launch or RUD the problem with nuclear fallout is extremely low, mostly well contained and because of the long half-life of the isotopes radiation levels are very low . Once the reactor is fired up there are an enormous amount of short-lived radioisotopes generated in the fusion process and any planetary impact will have the serious consequences of a massive radioactive contamination and associated cleanup. You want to be real sure where you park the spacecraft (it will be orbiting something, possibly the sun) at the end of the flight that there is no chance of it coming back to intersect any planetary orbits in the future.

Another quirk of the nuclear thermal engine is that it is not particularly suitable for orbit insertion with any finesse. The long thermal time constant of the system and the need to keep the gas flowing to cool the reactor during spindown has quite a bit of variability in the current technology.

 

[Dotini]

In my respectful and humble opinion, before we hitch our wagon to a nuclear energy future on Earth - let alone in space - I think we should pause for a moment to consider a couple of things. Firstly, UFOs are now treated as factual if unknown technological phenomena, most importantly by bipartisan majorities in both houses of congress. Secondly, these phenomena have been reported hovering over virtually every nuclear installation on the planet since WWII.

 

[CalebJ]

In my respectful and humble opinion, before we hitch our wagon to a nuclear energy future on Earth - let alone in space - I think we should pause for a moment to consider a couple of things. Firstly, UFOs are now treated as factual if unknown technological phenomena, most importantly by bipartisan majorities in both houses of congress. Secondly, these phenomena have been reported hovering over virtually every nuclear installation on the planet since WWII.

Eh?

 

[RICHARD COLARCO]

I remember reading once that if a space vehicle had 1-G of acceleration available to it, that Mars is three days away.
Jupiter would take three weeks.

NERVA might have given us that capability had we fully developed it.

Sure, a constant one-g acceleration makes any interplanetary trip a walk in the park. However, when you do the math and discover how much actual thrust you need to move any respectable payload at one-g continuously, you come up with an engine that you can't lift into orbit.

F=ma. You can't escape it.