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sheepscreek 15 hours ago

What’s there not to like? Superconductors. Free electricity. No cooling necessary.

Put those three together and maybe it’s possible to push physics to its limits. Faster networking, maybe 4x-5x capacity per unit compared to earth. Servicing is a pain, might be cheaper to just replace the hardware when a node goes bad.

But it mainly makes sense to those who have the capability and can do it cheaply (compared to the rest). There’s only one company that I can think of and that is SpaceX. They are closing in on (or passed) 8,000 satellites. Vertical integration means their cost-base will always be less than any competitor.

jasonpeacock 15 hours ago | parent | next [-]

> No cooling necessary.

This is false, it's hard to cool things in space. Space (vacuum) is a very good insulator.

3 are ways to cool things (lose energy):

  - Conduction
  - Convection
  - Radiation
In space, only radiation works, and it's the least efficient of those 3 options.
SideburnsOfDoom an hour ago | parent | next [-]

> In space, only radiation works

it's worse, incoming radiation also works to heat up objects that are in sunlight and in space. And you want to be in sunlight for the solar panels.

This is why surface of the moon is at temperatures of -120C when it's night and +120C when it's day there.

And the sun's radiation also flips bits.

Yes, it's technically possible to work around all of these. There are existing designs for radiators in the shade of the solar panels. Radiation shielding and/or resistant hardware. It's just not even close to economic at datacentre scale.

13 hours ago | parent | prev | next [-]
[deleted]
sheepscreek 15 hours ago | parent | prev | next [-]

Superconductors.

IshKebab 15 hours ago | parent [-]

Magnets.

(We're just saying random physics things right?)

whh 14 hours ago | parent | next [-]

Could we use a constant stream of micro-asteroids as a heatsink?

emkoemko 14 hours ago | parent | prev | next [-]

i think so, next is Quantum right?

sheepscreek 14 hours ago | parent | prev [-]

No, just you. Superconductors don’t get hot. There is 0 resistance in superconducting mediums. Theoretically you could manufacture a lot of the electricity conducting medium out of a superconductor. Even the cheapest kind will superconduct in space (because it’s so cold).

Radiation may be sufficient for the little heat that does get produced.

shagie 8 hours ago | parent | next [-]

> Even the cheapest kind will superconduct in space (because it’s so cold).

Space is not cold or hot - it isn't. It's a vacuum. Vacuum has no temperature, but objects in space reach temperatures set by radiative balance with their environment. This makes it difficult to get rid of heat. On earth heat can be dumped through phase change and discharged (evaporation), or convection or any number of other ways. In space the only way to get rid of heat is to radiate it away.

Superconductors don't have any resistance - and so heating from resistance isn't present. However, no super conducting computers have been created.

https://en.wikipedia.org/wiki/Superconducting_computing

And yes, it is really impressive - but we're also talking about one chip in liquid helium on earth. One can speculate about the "what if we had..." but we don't. If you want to make up technologies I would suggest becoming a speculative fiction author.

Heating of the spacecraft would get it on the warm side.

https://www.amu.apus.edu/area-of-study/science/resources/why...

> The same variations in temperature are observed in closer orbit around the Earth, such as at the altitudes that the International Space Station (ISS) occupies. Temperatures at the ISS range between 250° F in direct sunlight and -250° F in opposition to the Sun.

> You might be surprised to learn that the average temperature outside the ISS is a mild 50° F or so. This average temperature is above the halfway point between the two temperature extremes because objects in orbit obviously spend more time in partial sunlight exposure than in complete opposition to the Sun.

> The wild fluctuations of 500° F around the ISS are due to the fact that there is no insulation in space to regulate temperature changes. By contrast, temperatures on Earth’s surface don’t fluctuate more than a few degrees between day and night. Fortunately, we have an atmosphere and an ozone layer to insulate the Earth, protect it from the Sun’s most powerful radiation and maintain relatively consistent temperatures.

If you want solar power, you've got to deal with the 250 °F (121 °C). This is far beyond the specification for super conducting materials. For that matter, even -250 °F (-156 °C = 116 K) is much warmer than the super conducting chip range of 10 K.

Furthermore, the cryogenic material boils off in space quite significantly (I would suggest reading https://en.wikipedia.org/wiki/Orbital_propellant_depot#LEO_d... or https://spacexstock.com/orbital-refueling-bottlenecks-what-i... "Even minor heat exposure can cause fuel to boil off, increasing tank pressure and leading to fuel loss. Currently, the technology for keeping cryogenic fuels stable in space is limited to about 14 hours.") You are going to have significant problems trying to keep things at super conducting temperatures for a day, much less a month or a year.

Even assuming that you can make a computer capable of doing AI training using super computers this decade (or even the next) ... zero resistance in the wire is not zero power consumption. That power consumption is again heat.

---

> Theoretically you could manufacture a lot of the electricity conducting medium out of a superconductor.

Theoretically you can do whatever you want and run it on nuclear fusion. Practically, the technologies that you are describing are not things that are viable on earth, much less to try to ship a ton of liquid helium into space (that's even harder than shipping a ton of liquid hydrogen - especially since harvesting it is non-trivial).

---

Computing creates heat. Maxwell's demon taught us that doing 1 & 1 and getting one creates heat. Every bit of computation creates heat - superconductor or no. This is an inescapable fact of classical computation. "Ahh," you say " - but you can do quantum computation"... and yes, it may work... and if you can get a quantum computer with a kilobit of qbits into space, I will be very impressed.

---

One of the things that damages superconductors is radiation. On earth we've got a nice atmosphere blocking the worst of it. Chips in space tend to be radiation hardened. The JWST is using a BAE RAD750. The 750 should be something that rings a bell in the mind of people... its a PPC 750 - the type in a Macintosh G3... running between 110 and 200 Mhz (that is not a typo, it is not Ghz but Mhz).

High temperature super conductors (we're not dealing with the 10 kelvin but rather about 80 kelvin (still colder than -250 °F) are very sensitive to damage to their lattice. As they accumulate damage they become less superconductive and that causes problems when you've got a resistor heating up in the cryogenic computer.

---

Your descriptions of the technology for superconducting computers is in the lab, at best decades from being something resembling science fact (much less a fact that you can lift into space).

sfink 13 hours ago | parent | prev | next [-]

Right. You build your computers out of superconductors, and they don't get hot.

Sadly, they also don't compute.

> Even the cheapest kind will superconduct in space (because it’s so cold).

Is this a drinking game? Take a drink whenever someone claims that heat is not a problem because space is cold? Because I'm going to have alcohol poisoning soon.

Let's see how cold you feel when you leave the Earth's shadow and the sun hits you.

ben_w 13 hours ago | parent | prev | next [-]

If/when we get high-performance superconducting computers, we wouldn't need to put the computers in space in the first place.

haddonist 13 hours ago | parent | prev [-]

You've invented a room-temperature superconducting material? No?

Didn't think so.

Currently available superconductors still need liquid nitrogen cooling, meaning they're not feasible for in-orbit installations.

roman_soldier 15 hours ago | parent | prev [-]

[dead]

pgalvin 15 hours ago | parent | prev | next [-]

Do you mean to suggest that computer hardware does not need to be cooled when it is in space? Or that it is trivial and easier to do this in space compared to on Earth? I don’t understand either claim, if so.

sfink 13 hours ago | parent | next [-]

The computer hardware only needs to run enough AI compute to be smart enough to convince Musk that it's working. It should be fine.

sheepscreek 15 hours ago | parent | prev [-]

Superconductors. Average temperature in space is around 4 K.

cyberax 15 hours ago | parent | next [-]

Even assuming that this la-la-land idea has merit, the equilibrium temperature at the Earth's orbit is 250 Kelvin (around -20C). The space around the Earth is _hot_.

sheepscreek 14 hours ago | parent [-]

There are people literally working on accomplishing this. I don’t understand what’s with the arrogance and skepticism.

Edit: Not trying to single out the above commenter, just the general “air” around this in all the comments.

I honestly believed folks on HN are generally more open minded. There’s a trillion dollar merger happening the sole basis of which is the topic of this article. One of those companies put 6-8,000 satellites to space on its own dime.

It’s not a stretch, had they put 5 GPUs in each of those satellites, they would have had a 40,000 GPU datacenter in space.

cyberax 14 hours ago | parent [-]

> There are people literally working on accomplishing this.

They're reinventing physics? Wow! I guess they'll just use Grok AI to fake the launch videos. Should be good enough for the MVP.

For the superconductivity idea to work, the entire datacenter needs to be shielded both from sunlight and earthlight. This means a GINORMOUS sun shield to provide the required shadow. But wait, the datacenter will orbit the Earth, so it also will need to rotate constantly to keep itself in the shadow! Good luck with station-keeping.

There's a reason the Webb Telescope (which is kept at a balmy 50K) had to be moved to a Sun-Earth Lagrange point. Or why previous infrared telescopes used slowly evaporating liquid helium for cooling.

> I don’t understand what’s with the arrogance and skepticism.

Because it's a fundamentally stupid idea. Stupid ideas should be laughed out.

I'm not talking about "stupid because it's hard to do" but "stupid because of fundamental physical limitations".

emkoemko 14 hours ago | parent | prev [-]

you do know about the Sun? Earth? and the Moon? where would you get this 4 kelvin?

DougN7 15 hours ago | parent | prev | next [-]

Why is there no cooling necessary?

sheepscreek 15 hours ago | parent [-]

Space is cold - 4 K. Superconductors.

grim_io 14 hours ago | parent | next [-]

Repeating the word "superconductor" does not convince anyone of anything.

sheepscreek 14 hours ago | parent | next [-]

I don’t care about convincing anyone. A question was asked and I answered the best I could with the time I had at hand.

Also read by comment above that discusses WHY superconductors could be the key to cooler electronics in space.

roman_soldier 14 hours ago | parent | prev [-]

[dead]

SideburnsOfDoom 2 hours ago | parent | prev [-]

Space is not cold. Space is not hot either. Temperature is a property of matter. Empty space does not have a temperature. It is also a perfect insulator for conduction and convection, and as for radiation: it's a problem because of the sun heating up objects via its radiation.

This is the basics, I'm not an expert. But I don't think that you have anything useful at all to say here.

browningstreet 15 hours ago | parent | prev | next [-]

Do you know the lifespan of those satellites? Do you know how many of those fall out (sorry, de-orbited) of space every year?

Do you know the cost of sending up a payload of them?

Do you know how much $$ you need to extract from those payloads to make the cost of sending them up make sense?

Do you know how much they've lied about Starlink revenue and subscription counts?

tenuousemphasis 15 hours ago | parent | prev [-]

Your exuberance for this topic is only matched by your lack of understanding about it.