Nuke Reactor on the MOON

[BeyondKnowledge]

Okay, I am not disputing the triple point, but now I'm more confused when looking up prssures at the surface. Isn't 0.0006 still considered a "high vacuum?" Way above the moon surface pressure. 

 If 1013 millibars is average surface pressure on earth.

And  3×10^-12 millibars is the moon's surface pressure.

That would make it the decimal number 0.000000000003.  Which is a hell of a lot lower than the 0.0006 triple point. Which would make the entire moon untenable for liquid water to exist above very low temperatures. 

I realize its not instant and the volume would sublimate  more slowly depending on temperature, but wouldnt taking polar lunar ice to out of its cold stable place and into sunlight be like dry ice on earth?  Or throwing a comet at the sun? 

What am I missing? What is Google misleading me on?

Is is possible to have a pressurized water pipeline open to lunar elements? 

Suppose they build a plant to melt the water ice under pressure, wouldn't it theoretically need a pressurized pipe to surround the transport pipe to maintain liquid flow to the distant sun-parched reactor, that needs 17,500 gallons of water daily for every megawatt?  

This nuclear plant sounds like an expensive nightmare of pressure regulation and airtight chambers. It would have to exist inside a pressure bubble and vent outside it simultaneously, and also have a complex network of double-pressurized water transport.

Well first of all, everything in a nuclear reactor is under pressure. There are different levels of pressure but even the containment dome of reactors on Earth are a little above atmospheric pressure unless open, being worked on. There is one loop through the reactor that is radioactive and the hottest, highest pressure, that is pumped through a heat exchanger to make the steam that turns the turbine. After the turbine there is a cooling radiator of some type then pumped back to the heat exchanger to be heated again.

This is two loops of fluid that never mix and are sealed from the outside world in normal operation.

On the Moon, the radiator would be kept in the always shaded area or use a big sealed tank that would get heated from the reactor during the day an allowed to cool and freeze at night. The tank could be shielded from the sunlight heat by having a second shed roof over it. The shed could also hold additional cooling pipes to cool down the hot water at night. SIimple and foolproof oncqe sized properly for the reactor. The tank itself would have to be huge and flat as only surface radiation and not air cooling would be used. 

And no about having to have a second pressurize pipe around the water pipes. There is no need for additional pressure and just insulation like for steam pipes would keep the day, night thermal effects from being a problem as long as there is some flow through the pipes. After all, they are insulated like a vaccume bottle, they only need to have a shiny covering with a gap to keep the sun from boiling them and they would cool down very slowly at night. 

Any standard plumbing is rated for over  100 psi in normal use and that is well above keeping water liquid.

And about the atmospheric pressure of vacuum near ice on the Moon. During sublimation, there is pressure there made by the water vapor. The faster the evaporation, the higher the pressure, and the cooler the ice gets from the evaperation. This makes the evaporation slow down by its very nature. 

That was covered in an episode of 'Moonbase 3'. There was something attacking an area near the base but it was found to be ice sublimating underground. It worked in waves because it cooled itself down as it became more active.

[IdeomotorPrisoner]

Okay, the water used in the reactor is covered. I still have hang-ups expanded on below. 

It's thermally feasible with insulation, continuous pressure and flow, and works similar to a radiator. Learned something knew about reactors and ability to reuse water. Thanks for clearing that up, great answer...

I guess you could do that... **BUT**

Wouldn't you have to build the reactor in the water ice rich shadowed part of the crater?  Wouldn't it HAVE to be there? Like it the same facility you melt the ice? In the coldest place on the moon. 

How do you fill the coolant tanks? 

I'm still hung up on how you turn a bunch of crater ice into contained liquid water to use in a reactor in the sunlit part, possibly miles away. .. Melting it is easier than GETTING IT TO the reactor to be used. It might be a major expensive challenge...

Deferring to Skynet...

It is technically feasible, but extremely challenging, to maintain liquid water in a pipeline on the Moon for several miles. The primary hurdles are related to the Moon's lack of atmosphere and extreme temperature fluctuations. 

Here's why and what's required:

1. Preventing evaporation and freezing

• Vacuum environment: Without an atmosphere, water boils instantly into vapor at virtually any temperature above freezing.

• Extreme temperatures: The lunar surface experiences temperatures ranging from scorching hot during the day to frigid cold at night. This could cause the water to boil off or freeze solid depending on the lunar cycle.

• Solution: High-performance insulation and active heating/cooling. The pipeline would require sophisticated insulation, potentially including vacuum-jacketed piping or multilayer insulation (MLI), to minimize heat transfer and maintain a stable internal temperature for the water. Active heating during the lunar night and cooling during the day would likely be necessary to keep the water within its liquid state. 

2. Maintaining pressure

• Vapor pressure: Even with good insulation, water would attempt to evaporate into the vacuum. Therefore, the pipeline would need to be pressurized above the water's vapor pressure at the target temperature to prevent it from boiling.

• Pumping power: Moving water over several miles, even with the Moon's weaker gravity, would require substantial pumping power to overcome frictional losses and maintain the necessary pressure throughout the pipeline length. 

3. Construction and maintenance challenges

• Building on the Moon: Constructing such a pipeline on the Moon's surface would be a major engineering feat, possibly involving robotic construction and utilization of lunar resources like aluminum extracted from regolith.

• Micrometeorites: The pipeline would be vulnerable to punctures from micrometeorite impacts, requiring robust design and potentially robotic repair systems. 
In essence, while the idea of a pressurized, insulated pipeline for water on the Moon is theoretically possible, it presents immense technical and logistical challenges. It would necessitate advanced materials science, sophisticated thermal management systems, and robust robotic construction and maintenance capabilities to overcome the harsh lunar environment. 

what other then a pipeline is a possible way to transport water to the always sunlit reactor? 

Using pressurized Moon Semi Trucks and just drive the water to the coolant tank reservoir?  Or have an ice mine and transport the ice ore by Moon truck or moon train to the facility at the distant power plant where it's melted to coolant.  Either way you have to get A LOT of ice or water from A to B. 

Im sure it can all be done, but why we cant just deploy a square kilometer of solar panels per every 124.8  megawatts of power is beyond me. We could power 75,000 earth homes with something the same size as the array China is launching for their solar space station. But no, we want a nuclear reactor on the Moon! Because others are doing it. 

The part of the moon always in sunlight is like the one place solar panels are optimal and giving you their best.  Its like going to a waterfall and building a wind farm.

[Maxmars]

I had heard of a technology not in use (maybe?) that reduced the water requirements by encapsulating the fuel in ceramic pellets, rumored to be "unscrambleable" even dry, it would not melt down...

was that real...or some sci-fi I read long ago that I'm confusing with reality....

All that to say... couldn't there be a different approach to a reactor
in fractional gravity and no atmosphere to speak of?

[argentus]

You could build a printer that uses moon material to print other structures or even non planetary craft that could be launched easier with the lower gravity there.

Great idea!   There's a gob of basalt on the moon, which would make an excellent building material, crushed, as aggregate, slabs, whatever!

[imitator]

I had heard of a technology not in use (maybe?) that reduced the water requirements by encapsulating the fuel in ceramic pellets, rumored to be "unscrambleable" even dry, it would not melt down...

was that real...or some sci-fi I read long ago that I'm confusing with reality....

All that to say... couldn't there be a different approach to a reactor
in fractional gravity and no atmosphere to speak of?

Maybe related: NASA & DOE Research
 Microreactor project completes coolant system testing

The reactor uses liquid metal cooling, says it's ideal for environments like the Moon.

On July 28, 2025, INL announced a major milestone: the Primary Coolant Apparatus Test (PCAT)—a non-nuclear simulation of MARVEL’s cooling loop—completed a successful three-month validation test, confirming that the reactor’s natural circulation cooling system works reliably without pumps or water.

[IdeomotorPrisoner]

Well... There you go..  All my basic criticism withdrawn.

Go reactor on the moon with liquid metal cooling. I forget it's not a three mile island technology-wise anymore.  And possibly want to find a way to criticize this retarded dick measuring contest with China to bring nuclear power to the moon and be first to depleted its resources too. 

But that looks like a nice and compact unit for module living.

[quintessentone]

Lunar Madness Incoming... 

Sean Duffy... the former reality TV star turned Transportation Secretary announced US plan to build nuke reactor on MOON by 2030 in direct challenge to Russia and China new space race.

A directive from Nasa says that such an American nuclear reactor on the moon will establish US “keep-out” zones on the lunar surface.

They say it's to further stop rivals like Moscow and Beijing from effectively colonising the Moon. 
Uh-huh… sure it is. We’ll see how that plays out.  

https://www.thesun.co.uk/news/36159822/u...sia-china/

https://www.politico.com/news/2025/08/04...s-00492172

The lunar south pole is the real estate jackpot: ice, minerals, Helium‑3, and near-constant sunlight... ingredients for power projection! 

I think a reactor there functions as electromagnetic turf claim... it will be a high-tech flag in the ground, a de facto land claim.

What could possibly go wrong? Just a little radioactive fallout on the Moon, no big deal…

[Image: https://denyignorance.com//images/addsmi...atriot.gif]

So the imperial colonization spans out into space now. When will it stop? This is the stuff the makes never-ending wars.

[imitator]

This is the stuff the makes never-ending wars.

Funny how the U.S. seems to want to be the first to say: Get off my lawn!... on the Moon.
I guess these treaties were made to be broken... 

The Outer Space Treaty (1967) — The Foundation of Space Law
Established that outer space, including the Moon, is not subject to national appropriation by sovereignty, use, occupation, or any other means.

Outer Space Treaty It prohibits the establishment of military bases, fortifications, weapons testing, or maneuvers on the Moon... but allows the use of military personnel for peaceful scientific purposes.

UNITED NATIONS The Moon and other celestial bodies must be used for peaceful purposes, with free access for all states.

[Bush Master]

Nuke the Moon! Let's Do It!

[IDELB2006]

Funny how the U.S. seems to want to be the first to say: Get off my lawn!... on the Moon.
I guess these treaties were made to be broken... 

The Outer Space Treaty (1967) — The Foundation of Space Law
Established that outer space, including the Moon, is not subject to national appropriation by sovereignty, use, occupation, or any other means.

Outer Space Treaty It prohibits the establishment of military bases, fortifications, weapons testing, or maneuvers on the Moon... but allows the use of military personnel for peaceful scientific purposes.

UNITED NATIONS The Moon and other celestial bodies must be used for peaceful purposes, with free access for all states.

Establishing a base on the moon is not necessarily militaristic in nature. It just a bit of friendly cold war to keep China honest.