zlacker

[parent] [thread] 73 comments
1. M95D+(OP)[view] [source] 2025-02-26 21:02:26
> Some parts of the moon are permanently shadowed and therefore extremely cold, as low as -173 °C. This means that no energy or water would need to be expended to cool the data center.

That doesn't sound right to me. If there's no air, then only black body radiation can be used to cool the data center. That means a massive radiator, a lot larger than a heat-to-air radiator+fan used on earth.

replies(10): >>dekhn+i >>JoeAlt+v >>mppm+X7 >>M95D+D8 >>__Matr+39 >>foxyv+cm >>RajT88+AE >>trhway+3G >>scottl+fS >>amaran+FS
2. dekhn+i[view] [source] 2025-02-26 21:04:39
>>M95D+(OP)
I agree (problem for satellites), but then I wondered if you could dissipate the heat into the ground in a large area.
replies(1): >>perihe+t1
3. JoeAlt+v[view] [source] 2025-02-26 21:06:09
>>M95D+(OP)
Conduction through the ground? Or run coolant through buried pipes. Just a pump; no significant energy to cool, just move the coolant.
replies(2): >>ok_dad+F2 >>xattt+j8
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4. perihe+t1[view] [source] [discussion] 2025-02-26 21:11:59
>>dekhn+i
Isn't moon sand a very high thermal insulator?

edit:

https://pmc.ncbi.nlm.nih.gov/articles/PMC9646997/ ("Thermophysical properties of the regolith on the lunar far side revealed by the in situ temperature probing of the Chang’E-4 mission")

Comparing against reference tables, it's more insulating than rock wool insulation,

https://www.engineeringtoolbox.com/thermal-conductivity-d_42...

replies(2): >>dekhn+K3 >>Indrek+36
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5. ok_dad+F2[view] [source] [discussion] 2025-02-26 21:18:33
>>JoeAlt+v
Just ship all that heavy coolant up there first
replies(4): >>ceejay+J4 >>M95D+l6 >>French+x8 >>Valgri+iC
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6. dekhn+K3[view] [source] [discussion] 2025-02-26 21:24:04
>>perihe+t1
There's a reason I state my dumb ideas out loud :)
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7. ceejay+J4[view] [source] [discussion] 2025-02-26 21:31:28
>>ok_dad+F2
You'd probably use lunar water from the ice that's believed to be in shadowed craters at the poles.
replies(1): >>ok_dad+qZ
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8. Indrek+36[view] [source] [discussion] 2025-02-26 21:40:48
>>perihe+t1
Rockwool is much better thermal insulator in vacuum as well…
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9. M95D+l6[view] [source] [discussion] 2025-02-26 21:42:38
>>ok_dad+F2
... and digging/drilling equipment.
replies(1): >>JoeAlt+58
10. mppm+X7[view] [source] 2025-02-26 21:54:12
>>M95D+(OP)
They've got it all figured out, you just don't understand. Basically, the plan is:

1. Put data on the moon

2. ???

3. Profit

For more info, check out their promotional video: https://www.lonestarlunar.com/video

replies(3): >>uberma+ep >>leland+rz >>motore+PS
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11. JoeAlt+58[view] [source] [discussion] 2025-02-26 21:54:55
>>M95D+l6
Or just burying equipment. Everythng is very cold. No need to get deep. Cover them in regolith, freely available.
replies(1): >>ok_dad+AZ
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12. xattt+j8[view] [source] [discussion] 2025-02-26 21:56:27
>>JoeAlt+v
Why not do the same on Earth?

For all the heroics needed to establish this ok the moon, the efforts and costs are much less back home.

replies(2): >>JoeAlt+5d >>01HNNW+OU
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13. French+x8[view] [source] [discussion] 2025-02-26 21:57:20
>>ok_dad+F2
What's the expected lifetime of the average hard-drive in a datacenter? And does Amazon allow next day delivery to the Moon?
14. M95D+D8[view] [source] 2025-02-26 21:58:00
>>M95D+(OP)
I wonder if this info came from the Intuitive Machines or from article editor?

I can't find anything related to cooling on Intuitive Machines website. BTW, the website looks like investor bait, not a real company that has a future.

replies(1): >>arp242+Hr
15. __Matr+39[view] [source] 2025-02-26 22:00:39
>>M95D+(OP)
I don't think the use case requires much compute. It just has to hash the files maybe once per day and transmit:

> yes, the files are still here if you need them--well out of reach of pretty much everybody.

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16. JoeAlt+5d[view] [source] [discussion] 2025-02-26 22:26:54
>>xattt+j8
Right; its a one-and-quarter-second to the moon. High data center latency.
replies(1): >>xattt+4e1
17. foxyv+cm[view] [source] 2025-02-26 23:35:27
>>M95D+(OP)
A 1 meter square heat exchanger in a vacuum at 20C will emit about 1 kilowatt at -173C. So about as much as a small space heater per small panel. So a 1 megawatt datacenter would need about 300,000m^2 or 0.3 km^2 of surface area to cool it.

But geothermal cooling would be great on the moon too. Run a pipe 2 meters under the lunar surface and it is -21C.

I think the whole idea though is to make a low wattage space-stead so you can store copies of Moana out of reach of Disney cease and desist letters.

replies(4): >>solid_+1n >>lmm+Ds >>roboca+KD >>eru+vO
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18. solid_+1n[view] [source] [discussion] 2025-02-26 23:42:28
>>foxyv+cm
> But geothermal cooling would be great on the moon too. Run a pipe 2 meters under the lunar surface and it is -21C.

Isn't the moon geologically dead though - no water or geological movements?

I worry this would just result in the ground absorbing the waste heat and eventually becoming too warm to effectively cool anything. Especially because the ground itself would eventually still be limited by the rate of radiative cooling into space, right?

replies(2): >>szvsw+Ln >>foxyv+kye
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19. szvsw+Ln[view] [source] [discussion] 2025-02-26 23:47:06
>>solid_+1n
You have to worry about changing the ground temperature even on earth FYI. When designing district heating/cooling systems with borehole fields, one of the things that you check for is to make sure that you don’t inject too much heat (or extract too much) seasonally - ideally it’s roughly balanced so any drift year over year is small.

Obviously things like the diffusivity (so conductivity, mass, density etc) of the ground matter a lot, as does the rate of heat exchange at the surface for it to reject (or absorb) heat to the environment.

replies(1): >>solid_+po
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20. solid_+po[view] [source] [discussion] 2025-02-26 23:52:11
>>szvsw+Ln
Right, I'm roughly aware that's a concern on Earth too which is why I was wondering. How's the thermal conductivity of the moon?
replies(3): >>szvsw+Ir >>qskous+9z >>lstodd+rF
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21. uberma+ep[view] [source] [discussion] 2025-02-26 23:58:47
>>mppm+X7
This is as big a scam or waste as those solar mirror people. Throwing a USB stick out the lunar rover window and calling it a data center. Data centers usually do stuff other than sit in the dust.

Feel free to invest though, perhaps if you feel good about discarding hard drives on the moon I could interest you in space mirrors and for a low low price I'll lease you the spot where your harddrive lands for 100 years.

replies(1): >>dylan6+2F
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22. arp242+Hr[view] [source] [discussion] 2025-02-27 00:18:07
>>M95D+D8
It came from:

"Amit Verma, a professor of electrical engineering at Texas A&M University Kingsville who is not affiliated with the project, says there may be technical advantages to hosting data on the moon as well. Some parts of the moon are permanently shadowed and therefore extremely cold, as low as -173 °C. This means that no energy or water would need to be expended to cool the data center. And the electrical components will perform more efficiently."

I'm guessing Verma only thought about the electrical aspects, and simply didn't think about the different atmospheric conditions (i.e. not having one) as that's outside of the conditions an electrical engineer typically deals with. I can see how someone can make such a "oops, didn't think of that" mistake when a journalist asks for a comment.

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23. szvsw+Ir[view] [source] [discussion] 2025-02-27 00:18:08
>>solid_+po
Looked up some papers, and seemingly super low compared to what I would have initially guessed - probably because it’s porous/fluffy/sharp dust with lots of small voids/less compacted I’m guessing. Like, orders of magnitude less than the ground on earth. Not my area of expertise though and was just cursorily skimming papers for values. Specific heat cap and density seem like what you would expect for any rocky materials.
replies(1): >>justin+U31
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24. lmm+Ds[view] [source] [discussion] 2025-02-27 00:26:24
>>foxyv+cm
> geothermal cooling would be great on the moon

Surely it's selenthermal cooling at that point.

replies(1): >>foxyv+PT1
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25. qskous+9z[view] [source] [discussion] 2025-02-27 01:37:07
>>solid_+po
Geothermal heat transfer is greatly affected by the moisture of the soil, which on the moon would be pretty low as you can imagine.
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26. leland+rz[view] [source] [discussion] 2025-02-27 01:41:05
>>mppm+X7
Digital, yeah? Digital, right? Hey, rocket! https://www.youtube.com/watch?v=KuTSAeFhdZU
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27. Valgri+iC[view] [source] [discussion] 2025-02-27 02:11:16
>>ok_dad+F2
You could probably use significantly less coolant if you're using heat pipes. The coolant is mainly gaseous and only a small mass remains liquid during the cycle
replies(1): >>ok_dad+EZ
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28. roboca+KD[view] [source] [discussion] 2025-02-27 02:22:28
>>foxyv+cm
> Run a pipe 2 meters under the lunar surface and it is -21C.

I would expect the regolith to be a poor thermal conductor. Not useful for heat exchanger

replies(1): >>LeifCa+DJ
29. RajT88+AE[view] [source] 2025-02-27 02:28:26
>>M95D+(OP)
Putting a data center on the moon is not the real business.

The real business is the fake contracting companies the founders own who will hoover up all the contracts, do a lot of on-paper contracting making the founders very wealthy before the fake lunar business goes bankrupt.

replies(1): >>grande+ME
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30. grande+ME[view] [source] [discussion] 2025-02-27 02:31:00
>>RajT88+AE
Unfortunate that this is how pessimistic a startup forum is, but it’s no fault of yours and I don’t think you’re wrong.
replies(1): >>motore+ES
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31. dylan6+2F[view] [source] [discussion] 2025-02-27 02:33:13
>>uberma+ep
> Throwing a USB stick out the lunar rover window and calling it a data center. Data centers usually do stuff other than sit in the dust.

Okay, so here me out: the ultimate cold storage for someone like Iron Mountain. You'd have to understand that you'll need a minimum of 96 hours for retrieval time, and it's gonna be expensive to get that retrieval rocket there and back. Or, build a big dish and send the data via satellite signals.

replies(2): >>LeifCa+sJ >>uberma+cO1
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32. lstodd+rF[view] [source] [discussion] 2025-02-27 02:37:55
>>solid_+po
No one ever drilled the Moon to any useful extent. All we know is that it's mostly dusty on top.
33. trhway+3G[view] [source] 2025-02-27 02:44:29
>>M95D+(OP)
> If there's no air, then only black body radiation can be used to cool the data center.

to put it into numbers - at 80C (353K) 1m2 radiates 880Watts

I think though that instead of the Moon we'll be putting data centers into orbit - for 1KWt GPU we'll need 5m2 solar panels and 1m2 radiator - all together under 10kg, ie. $1000 at Starship prices while the GPU itself is $20K+ .

The kicker here is that the Starship launch price is cheaper than installing solar on the ground ( $2K/KWt and higher)

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34. LeifCa+sJ[view] [source] [discussion] 2025-02-27 03:24:20
>>dylan6+2F
If you want your data to survive a global nuclear armageddon or Chicxulub impactor, a flash drive on the moon isn't a bad place to put it.

You know what they say, 3-2-1 backup: three copies of your data, stored on two different types of media, with one copy kept offsite to guard against common-cause data loss. Depending on the cause, off-site could be a difficult place to go!

replies(3): >>andrew+IL >>01HNNW+EU >>uberma+ZM1
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35. LeifCa+DJ[view] [source] [discussion] 2025-02-27 03:25:56
>>roboca+KD
Probably orders of magnitude better than hard vacuum, though.
replies(3): >>eru+BO >>ikiris+gR >>foxyv+uze
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36. andrew+IL[view] [source] [discussion] 2025-02-27 03:47:24
>>LeifCa+sJ
Well an un-hardened flash drive would probably stop working within minutes of being exposed to all those rads, but I’m just being pedantic :p
replies(1): >>eru+4O
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37. eru+4O[view] [source] [discussion] 2025-02-27 04:11:07
>>andrew+IL
You can solve that problem in situ, by piling a few metres of regolith on top.
replies(1): >>dylan6+bS1
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38. eru+vO[view] [source] [discussion] 2025-02-27 04:15:46
>>foxyv+cm
> But geothermal cooling would be great on the moon too. Run a pipe 2 meters under the lunar surface and it is -21C.

It won't stay -21C for very long, if you pump heat into it.

Really, radiative cooling is your only longer term option.

Btw, you can make your radiative cooling a lot more efficient than you gave in your example, if you run it at a higher temperature. Radiated power grows with the fourth power of (absolute) temperature. So, run your chips at something closer to eg 100C and you radiate more than 2.5x as much power.

replies(1): >>foxyv+jV1
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39. eru+BO[view] [source] [discussion] 2025-02-27 04:17:15
>>LeifCa+DJ
For conductive cooling, sure.

But for radiative cooling, vacuum with a clear view of the night sky is orders of magnitude better.

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40. ikiris+gR[view] [source] [discussion] 2025-02-27 04:52:23
>>LeifCa+DJ
Their point is sure, you locally dump the heat. Where does it go then? There's not ground water to act as a sink so you're stuck with basically a big regolith insulator, and there's barely any atmosphere, so you're back to the black body of the ground with extra steps and a large local sink. That sink isn't infinite when you're talking even house scales, much less thermal scales of a large datacenter. Cooling works on earth because the atmosphere moves the heat.
41. scottl+fS[view] [source] 2025-02-27 05:05:52
>>M95D+(OP)
conduction direct into the ground
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42. motore+ES[view] [source] [discussion] 2025-02-27 05:11:43
>>grande+ME
> Unfortunate that this is how pessimistic a startup forum is (...)

It's a startup forum. People commenting here have real world experience with startups. Might they not be commenting on what they see and know?

replies(1): >>grande+IT
43. amaran+FS[view] [source] 2025-02-27 05:12:01
>>M95D+(OP)
You could probably sink plates of some thermally conducting material into the regolith itself?

Like geothermal cooling, kinda. Possibly a passive solution could work somewhat?

It'll be a temporary solution, the regolith will heat up eventually, but maybe it'll work for long enough?

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44. motore+PS[view] [source] [discussion] 2025-02-27 05:15:10
>>mppm+X7
> They've got it all figured out, you just don't understand.

I'd love to know how they plan to offset the cost of moving every single nut and bolt to the moon with... Cheaper cooling?

I mean, Microsoft experimented with sinking data centers under the ocean. That's certainly cheaper and more performant than shooting a rocket to the moon. That experiment ended. Why?

replies(1): >>connic+jU
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45. grande+IT[view] [source] [discussion] 2025-02-27 05:27:29
>>motore+ES
Did you stop after the first half of my sentence?
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46. connic+jU[view] [source] [discussion] 2025-02-27 05:37:05
>>motore+PS
Iirc a big issue they had was the fact it's nearly impossible to service the interior once you sink it down. That would basically get an order of magnitude worse with it on the dark side of the moon.
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47. 01HNNW+EU[view] [source] [discussion] 2025-02-27 05:42:40
>>LeifCa+sJ
I thought flash storage leaked charge if it wasn't powered on and scrubbing itself regularly. Maybe stone tablets on the Moon.
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48. 01HNNW+OU[view] [source] [discussion] 2025-02-27 05:45:37
>>xattt+j8
There's a serious lack of terraforming here on Earth.

Oh, we're overpopulated? Buy some single-family homes, buy out the government, and upzone it into apartments. You're still cheaper than space flight and with a shorter commute to work than Rapture

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49. ok_dad+qZ[view] [source] [discussion] 2025-02-27 06:52:30
>>ceejay+J4
Just heat up all that super cooled ice first
replies(1): >>ceejay+An1
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50. ok_dad+AZ[view] [source] [discussion] 2025-02-27 06:54:56
>>JoeAlt+58
Rock is so well known as a thermal insulator that we build buildings from it (brick, concrete, stone blocks). I don't think it's going to help much with your heat transfer problem.
replies(1): >>JoeAlt+gA2
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51. ok_dad+EZ[view] [source] [discussion] 2025-02-27 06:56:37
>>Valgri+iC
There is a certain amount of energy you need to move from the chips to the atmosphere or to the geology, and a liquid coolant vs a gaseous coolant will make a BIG difference in how much of that heat you can move. I don't know why I am arguing, putting a data center on the moon is dumb as hell.
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52. justin+U31[view] [source] [discussion] 2025-02-27 07:54:24
>>szvsw+Ir
Might need to pour a bunch of water on the soil to increase the thermanl conductivity and make sure to never heat it above freezing?
replies(1): >>foxyv+b0l
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53. xattt+4e1[view] [source] [discussion] 2025-02-27 10:04:23
>>JoeAlt+5d
Priorities!
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54. ceejay+An1[view] [source] [discussion] 2025-02-27 11:49:04
>>ok_dad+qZ
I like how you’ve done a complete 180 on the problem here.
replies(1): >>ok_dad+qn2
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55. uberma+ZM1[view] [source] [discussion] 2025-02-27 15:10:32
>>LeifCa+sJ
Let's tale it at face value that a hard drive on the moon does not entropy. Let's also take it as given that the data is so important that you would pay millions of dollars to place it on the moon and millions more to get it back when needed in the event that all your other forms of backup failed due to some global catastrophe.

1) At the moment, we can't even get living people off the international space station let alone land on the moon and take off from the same spot twice.

2) If a space based proof of concept was practical, why would we not store our hard drive on the ISS. It is looking for some excuse to remain in operation and we can already come and go from it on a semi-regular basis?

3) If there was a global catastrophe to the extent that only moon based archives remained, then how are we going to go get them? This crisis destroys all data archives but preserves our space program?

4) Once we did get the drive back, what exactly might we do with it considering all other forms of data storage were destroyed?

5) If the data on the drive was so valuable that we were willing to pay millions of dollars for the chance that after Armageddon we could still get it back... Then why would the Chinese not just wait for us to place the drive then go get it themselves? Surely you would never encrypt it as the key would be just as vulnerable to loss as the data.

replies(1): >>dylan6+wU1
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56. uberma+cO1[view] [source] [discussion] 2025-02-27 15:18:39
>>dylan6+2F
"you'll need a minimum of 96 hours for retrieval time"

We can't even get people back from the ISS in 96 days.

replies(1): >>dylan6+1S1
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57. dylan6+1S1[view] [source] [discussion] 2025-02-27 15:38:57
>>uberma+cO1
That's because of the incompetence of the manufacturer of the craft used, not humanity's inability to make this happen. So this isn't even close to being a fair comparison.
replies(1): >>uberma+Fi2
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58. dylan6+bS1[view] [source] [discussion] 2025-02-27 15:39:45
>>eru+4O
Just build the data center in the moon caves and live regolith dust free
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59. foxyv+PT1[view] [source] [discussion] 2025-02-27 15:51:31
>>lmm+Ds
Thank you for the correction. Shows my geocentric thinking.
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60. dylan6+wU1[view] [source] [discussion] 2025-02-27 15:54:57
>>uberma+ZM1
> 1) At the moment, we can't even get living people off the international space station let alone land on the moon and take off from the same spot twice.

This is absolute garbage. It's not even close to being true. Since the astronauts arrived on the Boeing craft, SpaceX has delivered and retrieved other astronauts. They are not still on the ISS because there's no ability to bring humans back, but because of a scheduling logistics situation.

Continuing to push this scheduling snafu as being unable is just nonsense, and you are as well for pushing it.

> 2) If a space based proof of concept was practical, why would we not store our hard drive on the ISS. It is looking for some excuse to remain in operation and we can already come and go from it on a semi-regular basis?

There's only so much space on the ISS. Also, it's being decommissioned soon, so unless some company wants to take it over as a business--which NASA is open to yet no takers--they've contracted SpaceX to de-orbit the station.

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61. foxyv+jV1[view] [source] [discussion] 2025-02-27 15:58:34
>>eru+vO
> It won't stay -21C for very long, if you pump heat into it.

You are right, and also it would require digging which is a lot harder than laying out panels on the surface. Back of the napkin it's a tossup depending on the conductivity of lunar sub-surface material and how much pipe you lay. Just like on Earth.

> Btw, you can make your radiative cooling a lot more efficient than you gave in your example

This is true too, heat pumps could even get higher radiator temps than 100C if you like.

replies(1): >>eru+H84
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62. uberma+Fi2[view] [source] [discussion] 2025-02-27 18:29:46
>>dylan6+1S1
Are you suggesting that we "simply" build an entire space transit system so people can come and go to the moon on short notice in order to support hard drive archiving?
replies(1): >>dylan6+Ep2
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63. ok_dad+qn2[view] [source] [discussion] 2025-02-27 18:59:34
>>ceejay+An1
No, I’m saying it’s stupid to put this on the moon. Every time someone says, “just do this” there are complexities and costs that they don’t account for. Where will you get the immense energy needed to melt supercooled ice?! It’s ridiculous that I’m even arguing, it’s such a stupid idea.
replies(1): >>ceejay+ez2
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64. dylan6+Ep2[view] [source] [discussion] 2025-02-27 19:13:07
>>uberma+Fi2
Of course. Just like we're talking about simply building a data center on the moon
replies(1): >>uberma+3X2
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65. ceejay+ez2[view] [source] [discussion] 2025-02-27 20:21:33
>>ok_dad+qn2
> No, I’m saying it’s stupid to put this on the moon.

I agree with that. Just not for the heating/cooling reasons.

> Where will you get the immense energy needed to melt supercooled ice?!

The problem was too much heat. Now it's too little heat. You can't have both. The energy comes from the server farm. The coolant comes from the ice. You melt your first ice with the heat from the server farm (or an initial solar field).

replies(1): >>ok_dad+RB2
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66. JoeAlt+gA2[view] [source] [discussion] 2025-02-27 20:28:32
>>ok_dad+AZ
Rats. I can't seem to find the thermal properties of regolith. Mostly rock, some heavy metals.
replies(1): >>ok_dad+nr3
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67. ok_dad+RB2[view] [source] [discussion] 2025-02-27 20:36:26
>>ceejay+ez2
The ice isn’t in one place, it’s spread around in the regolith at varying densities. How do you collect and melt it? Sure you have heat and nothing to do with it but your ice isn’t all in a neat pile. My point is that you can go on and on like this and come up with a thousand ways the project will fail before it’s even started. Anyways, I’m done arguing, we both agree it’s stupid but just for different reasons.
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68. uberma+3X2[view] [source] [discussion] 2025-02-27 22:58:51
>>dylan6+Ep2
So, completely out of the realm of possibility. Got it.
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69. ok_dad+nr3[view] [source] [discussion] 2025-02-28 03:31:36
>>JoeAlt+gA2
I read somewhere else that regolith is spiny and porous, and with the leading theory of the moon being that it was the result of some massive object hitting Earth a long time ago, and then the ejected material coalescing in orbit and cooling, it makes sense to me that it would be more of an insulator than a conductor. I only know a bit of materials science from what I learned in nuclear power school back in the day, but for a conductor you want to have, generally, no air voids. I recall learning how bubbles in the steel for the plant could not only lead to failures, but also lead to thermal stress points because heat would build up on the "thinner" cross section of metal when there were pores all over (heat transfer being dependent a lot on the cross sectional width, IIRC). Anyways, it's unlikely they'll actually build anything on the moon anytime soon, especially a "data center".
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70. eru+H84[view] [source] [discussion] 2025-02-28 10:38:46
>>foxyv+jV1
> This is true too, heat pumps could even get higher radiator temps than 100C if you like.

I'm not sure that actually works out to your advantage, because the heat pumps themselves produce extra heat. But I haven't done the math on that.

replies(1): >>foxyv+nue
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71. foxyv+nue[view] [source] [discussion] 2025-03-03 17:00:47
>>eru+H84
Heat pumps are typically 200-400% efficient. That is, they move 2-4x as much heat as they produce to move that heat. Although that is usually radiating energy to a fairly warm atmosphere. If they are pumping into an extremely cold environment you will get insane efficiencies since you are 'going with the flow' with regards to entropy increase.
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72. foxyv+kye[view] [source] [discussion] 2025-03-03 17:14:06
>>solid_+1n
Geological activity is usually a problem for geothermal cooling. Conductivity of lunar subsurface is your main problem. Generally what makes geothermal really effective is the monstrous thermal mass of solid and liquid material compared to air as well as it's much higher conductivity. While that is true on Earth, on the Moon things are very different.

The problem isn't so much geological activity or lack thereof, as the nature of lunar regolith. Lunar regolith has a conductivity of 0.004W/mK. That is lower than aerogel! So unless the subsurface has a much higher conductivity, using subsurface cooling would be doomed.

Edit: Lunar Regolith is only the first 4-5 meters of the lunar surface.

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73. foxyv+uze[view] [source] [discussion] 2025-03-03 17:18:43
>>LeifCa+DJ
The regolith is 0.004W/m2K. Less than aerogel. Less than an open vacuum! Ouch!

Although the regolith is only 4-5 meters thick, so you could probably just go under it and see what the subsurface is like with regards to conductivity.

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74. foxyv+b0l[view] [source] [discussion] 2025-03-05 16:37:02
>>justin+U31
Water would boil on the moon, any ice would sublimate. You would be better off just compacting the regolith.
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