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Comment by nimbius | Hacker News Reader

it doesnt need to last long enough for the first permanent moon colony, just long enough to get the investors excited and bump the stock.

frankly i think a moon colony thats anything but underground is a laughably myopic idea. the delta T for the moon is pretty insane.

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Delta T? Please explain. I'm familiar with DeltaV, but pretty much all the delta T usages I have seen refer to a time interval.

https://en.wikipedia.org/wiki/Delta-v

Delta T in this case is probably referring to the change between the minimum and maximum temperatures experienced on the surface of the moon. In other words, the delta between something getting really hot spending 14 days in direct sunlight with no convection to cool it down and then getting really cold spending 14 days in darkness.

Delta T (for temperature) can also refer to the delta in temperature across an object as well. One side is very hot and one side is very cold. Often used when describing problems of relative thermal expansion.

> In other words, the delta between something getting really hot spending 14 days in direct sunlight with no convection to cool it down and then getting really cold spending 14 days in darkness.

Hmm. Could a buffer (e.g. water) be used? Basically... radiate heat out of the buffer when it's cold and move heat from the device into the buffer when it's warm?

Water could work as a buffer, but so could a rock, and this circles back to GGP's original point.

Similar reasoning (with perhaps higher focus on radiation than ∆T) applies to Mars, and is probably one of the side reasons Musk started The Boring Company.

Maybe, but it will definitely push technology a few steps forward. Big possibility something useful will be found along the way, maybe even in not related field but still.

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