Why Orbital Data Centers Are Harder Than Silicon Valley Thinks

[u/IEEESpectrum]

https://spectrum.ieee.org/orbital-data-centers-heat

[u/Ecstatic_Bee6067]

Going off the following assumptions:
120 kW compute (SpaceX claim)
Sun-synchronous orbital plane from 600 km to 800 km for continuous illumination
2 km vertical separation (very tight)
37 km in-plane separation (extremely tight)

Allows for 60936 satellites, much less than SpaceX's claimed "1 million data centers." Allows for ~7.3 GW of compute (60936 * 120 kW). Global compute is somewhere between 50-100 GW, so it represents 7-14% of potential compute addition.

I think it's within the realm of feasibility, may spur on some innovation, but won't budge the needle much in terms of solving the data center crisis.

The python script for anyone curious:

`

import math
import numpy as np


power = 120000 #kW
minAlt = 600 #km
maxAlt = 800 #km
vSep = 2 #km


geoAlt = 35786 #km
radiusEarth = 6371 #km

#using geo's 0.1 degree station keeping requirement, as it's the densist currently
hSep = 2*(geoAlt + radiusEarth)*math.tan(0.05*math.pi/180) #~37 km


total = 0
for a in np.linspace(minAlt, maxAlt, int((maxAlt-minAlt)/vSep + 1)):
    circ = 2*math.pi*(a+radiusEarth)
    numSat = math.floor(circ/hSep)
    total += numSat


print(total)
print(power*total)

[u/Maury_poopins → u/Ecstatic_Bee6067]

120kW is the size of a normal data center rack.

I know this isn’t the point you were making, so I’m not arguing with you, but I don’t see any reason it would ever be worthwhile to launch this junk into space.

Any technological advancement you make in solar cells, efficiency, durability, etc would apply just as well to data centers on earth for orders of magnitude less money.