zlacker

>>lawren+(OP)
I saw a few posts about this and thought it was a joke. This tweet sums it up:

YC company announces a giant data center in space

Startup Twitter: Makes so much sense, it will be so easy to cool in space!

Space Twitter: How the hell are they proposing to keep it cool??

https://x.com/mouthofmorrison/status/1831680658927669632

>>slyall+j2
But their video is so pretty! https://www.lumenorbit.com/

> As launch costs fall, orbital data centers will leverage 24/7 solar energy and _passive cooling_, rapidly deploying to gigawatt-scale, avoiding permitting constraints on Earth.

It sounds like they want to use copper heatspreaders and radiators to dump gigawatts into space. From those little pods connected to the spine... without any active cooling components

Oh dear.

>>throwu+m3
What manner of active cooling do you imagine might work in vacuum? Fans?

>>holler+y3
You use radiation for cooling in space. That obeys the Stefan-Boltzmann law with power scaling with T^4 (so you want the radiators as hot as possible). You can use passive elements, like heat-pipes to move heat to the radiators, but active elements like pumps for forced convection could make sense; and most importantly heat pumps are an active element that can boost the temperature of the radiators vs the thing you're keeping cool (thereby increasing the heat rejection capacity of a given radiator size).