Orbital Data Centers connecting directly to Starlink via laser

[Robotbeat]

BTW, part of this thread is the assumption that in-space direct satellite-to-satellite comms is significantly cheaper with lasers than with radio. Otherwise, why would SpaceX bother with lasers? So that's a potential advantage (above terrestrial datacenters also connected via Starlink).

It may or may not be cheaper but the lack of fcc spectrum allocation sure does help.

I would think satellites in MEO could communicate to the 550km fleet by just talking to satellites that are on the rim of the earth from the satellites view point.
1. Allows the laser links on 550km satellites to only look tangential to the earth. IE not up or down. Something they will already do to communicate to their in plane and adjacent planes.
2. Less interference from the earth or to the earth.

Youre not the only one who has said this, so let me clarify:

FCC allocation (and limited radio spectrum, etc) is a cost, so I’m including things like that in my stated assumption that lasers could be cheaper.

[OTV Booster]

We've had discussions on how to do ground stations on big water. With a gyro stabilized buoy to carry an array...

Just thinking.

Why gyrostablize, when you could have a quad antenna pyramid on the buoy with an IMU and steer the beam electronically?

I'm not a phased array or a buoy wallah but I do know there's limits to how far a beam can swing. Even with a quad array it might swing too extreme. The North Atlantic can get purty rough.


If it can be reliable without a gyro, so be it.

[Mark K]

I am still not seeing the use case for this.

Everything about isolated container data centers still makes more sense to me on Earth than in orbit, especially if you are talking high orbit. If we have a "semi-trailer" data center it is a heck of a lot cheaper than 13K per month to dump it next to a warehouse in, say, upper Michigan with a connection to cold Lake Superior water for cooling.

Latency?This would be quicker than MEO for sure. Power? Yes we will pay for power but that is cheap relative to the capital cost of the solar cells and especially the cooling which I feel people are writing off too easily. For big sustained power that is going to be an issue as you only get radiant heat loss so you will need to create shaded structure. If you are in low earth orbit you will need a lot of batteries to power you over the night periods, unless you have some kind of beamed power (more capital cost).

Starlink big connections make leaving the processing on Earth even easier with the good connectivity it allows
to out of the way places.

[Robotbeat]

I am still not seeing the use case for this.

Everything about isolated container data centers still makes more sense to me on Earth than in orbit, especially if you are talking high orbit. If we have a "semi-trailer" data center it is a heck of a lot cheaper than 13K per month to dump it next to a warehouse in, say, upper Michigan with a connection to cold Lake Superior water for cooling.

Latency?This would be quicker than MEO for sure. Power? Yes we will pay for power but that is cheap relative to the capital cost of the solar cells and especially the cooling which I feel people are writing off too easily. For big sustained power that is going to be an issue as you only get radiant heat loss so you will need to create shaded structure. If you are in low earth orbit you will need a lot of batteries to power you over the night periods, unless you have some kind of beamed power (more capital cost).

Starlink big connections make leaving the processing on Earth even easier with the good connectivity it allows
to out of the way places.

Solar cells can be extremely cheap. 6 cents per watt. Whole panels as cheap as 16 cents per watt. How much does a terrestrial 24/7 power station cost if you include fuel? Maybe $10/Watt? Way cheaper power in orbit is possible.

Cooling is already going to liquid for a lot of stuff (for instance, Google’s AI training chips and supercomputers), and you just need to pump that fluid to exterior radiator loops where you can passively radiate the heat to deep space for “free.” Yes, radiators can be heavy, but they don’t have to be expensive at all. And so if you solve launch costs with Starlink, thermal is also taken care of.

Energy intensive computing which isn’t very latency sensitive (AI training, scam mining, big data processing/analysis jobs, rendering, basically all supercomputer simulations) can be far from LEO where heat rejection and power production are both much better, potentially better and cheaper than on Earth.

[Robotbeat]

The data center need not be in vacuum. It’d be easier to put it in a somewhat pressurized nitrogen, air, or helium... or possibly a tank of nonconductive fluid for optimal heat transfer like is done in some supercomputers. The nonconductive liquid would double as radiation shielding. Would enable greater density than typical servers.



Just need to have pumps to do ensure continual flow:

[indaco1]

..

The small problem with that is each laser link receiver is exclusive during use. You would effectively have to use RF from the customer to the relay sat to schedule laser time on a relay receiver, and to service more than one customer at a time, you would need multiple receivers, separated sufficiently to not have beams potentially overlap.
...

The data center satellites just have to be connected to few ordinary Starlink satellites, leveraging existing stuff and frequencies, and they will be online.

Even better they could simply be upgraded and more massive double duty Starlink satellites sharing the same orbits, permissions, frequencies, laser links etc.

I can't really see any advantage for high orbit except for perennial solar power. Maybe EM knows who could help with batteries :-D

[vsatman]

FCC allocation (and limited radio spectrum, etc) is a cost, so I’m including things like that in my stated assumption that lasers could be cheaper.

As much as I know the FCC regulates the spectrum from 9 kHz to 300 GHz and 20+ THz lasers are not subject to FCC regulation

[Robotbeat]

FCC allocation (and limited radio spectrum, etc) is a cost, so I’m including things like that in my stated assumption that lasers could be cheaper.

As much as I know the FCC regulates the spectrum from 9 kHz to 300 GHz and 20+ THz lasers are not subject to FCC regulation

That’s my point.

[DigitalMan]

FCC allocation (and limited radio spectrum, etc) is a cost, so I’m including things like that in my stated assumption that lasers could be cheaper.

As much as I know the FCC regulates the spectrum from 9 kHz to 300 GHz and 20+ THz lasers are not subject to FCC regulation

That’s my point.

I found it interesting that in the video link posted in the SDA LEO thread yesterday, there was a comment regarding SAT -> SAT laser comms and additionally, SAT -> GROUND comms.

Laser comms could wind up being an interesting possibility for ground.

[Lar]

FCC allocation (and limited radio spectrum, etc) is a cost, so I’m including things like that in my stated assumption that lasers could be cheaper.

As much as I know the FCC regulates the spectrum from 9 kHz to 300 GHz and 20+ THz lasers are not subject to FCC regulation

That’s my point.

That AND they're more efficient (in use of 3d space, not necessarily power) since they can be so tight.

[Robotbeat]

FCC allocation (and limited radio spectrum, etc) is a cost, so I’m including things like that in my stated assumption that lasers could be cheaper.

As much as I know the FCC regulates the spectrum from 9 kHz to 300 GHz and 20+ THz lasers are not subject to FCC regulation

That’s my point.

That AND they're more efficient (in use of 3d space, not necessarily power) since they can be so tight.

They're more efficient per bit sent (because you can easily get much higher gain). Depending on the laser source, similar or slightly lower efficiency than ~30GHz radio per watt of photons.

[mlindner]

I'm not sure anyone in this thread actually knows anything about data centers based on some of the comments. A server rack in an average data center pulls 10 kilowatts of power per rack. In a data center like Amazon's or Google's where it's been custom designed they'll pull upwards of 30-40 kilowats of power per rack. Once you're at 4-5 racks you're at solar panels the size of the ISS's panels. And a good sized data center has dozens to hundreds of racks.

In space you can't convect or conduct heat away, which are the two most efficient forms of heat dissipation. You can only radiate heat away which becomes very difficult with so much energy consumption going on. The size of the radiators are going to be massive, likely much larger than the solar panels used to collect the energy in the first place.

Secondly you have radiation issues. Single bit upsets become huge issues and the hardware to handle that isn't cheap. Data corruption would become a massive issue given the density of the high performance compute. (As a percentage of volume, satellites have very little space dedicated to transistors.) The transistors would also be much smaller than is commonly used on spacecraft right now. DRAM would need to be some form of enhanced ECC memory more resiliant than even normal ECC.

Data centers are already really hard to build properly. (For example the recent case of one burning down in Europe.)

If you're looking for exotic places to build data centers, the new fad is to build them under water and underground because the water/earth insulates them from radiation effects and in water it becomes much easier to dissipate all that heat rather than having to pay for the rather extreme cooling systems modern data centers require. It can just use pumps to pull in external water, circulate it and then expel it. Putting them in space is the complete opposite of that both in terms of ease of access to electrical power, ease of cooling, and radiation environment. Data centers are being built next to hydroelectric dams so they can use the water for cooling and the cheap power from the dam. Data centers are also being built in places like iceland with it's low temperatures for air cooling, it's cheap geothermal power.

It's NEVER going to be the case that we'll put data centers in space until we built the data centers there in the first place and there's a massive in-space human presence already.

[Jarnis]

This is very true. I could see some point in building some on the Moon (underground) for the ultimate offsite backup and to support operations there without the ping/lag to Earth based servers, but even then this would be extremely expensive undertaking and makes no sense until there is a serious permanent human presence.

On orbit I don't see anything more fancier than a "router" existing anytime soon. So only whatever "brains" are required for efficient packet routing and even there you want to absolutely minimize the stuff you do because power consumption and heat are big issues. Even for terrestial routers as speeds and packet volumes go up.

[matthewkantar]

I dunno. If Starship can someday put a 150 ton data center in orbit for a couple of million dollars, the cooling and power can be worked out. Free land, free power, virtually unlimited connectivity, and impregnable security may make orbital server farms appealing.

[Keldor]

I dunno. If Starship can someday put a 150 ton data center in orbit for a couple of million dollars, the cooling and power can be worked out. Free land, free power, virtually unlimited connectivity, and impregnable security may make orbital server farms appealing.

For a couple million dollars, I could buy a huge parcel of land in the Sahara and build a nice building to hold my data center.  Plenty of sunlight for the solar panels, so power is "free".  Sure, cooling will be annoying, but the Sahara is a nice cool environment with easy ways to dissipate heat compared to low earth orbit.  Starlink can communicate to my data center in the Sahara just as easily as with a data cener in orbit.  My latency is nice and low for my customers in Europe, and I can build another one in, say, some salt flat in Nevada to serve North America.  At least they don't spend 40% of their time orbiting out over the Pacific far away from anyone like they would in orbit.

 Out in the middle of the Sahara, it's super easy to get technicians and replacement parts too.  Just fly them in from across the world or something.  Much cheaper than trying to get them into orbit!  And they can work in the peace and comfort of an environment with free gravity and virtually zero risk of explosive decompression followed by asphixiation.

Of course, no one is going to build a data center in a remote part of the Sahara for what I should think are obvious reasons.  Every single one of those reasons is true for orbit as well, only many times worse.  I suppose there are worse places, like the bottom of the Marianas Trench, or in orbit around Jupiter, though.

Seriously, though.  Orbit is a terrible place to put anything that doesn't have a very good reason for requiring to be there.

[mlindner]

I dunno. If Starship can someday put a 150 ton data center in orbit for a couple of million dollars, the cooling and power can be worked out. Free land, free power, virtually unlimited connectivity, and impregnable security may make orbital server farms appealing.

Sure but what does that buy you? Land is highly available in the US already. Just most of it is so far away from civilization that people consider it worthless for most purposes. Also power isn't free in space as I just mentioned. You need to build and unfurl those solar panels. Even a Starship isn't big enough to launch them without some sort of autoassembly process, the same for the radiators.

Also there's one more aspect that's key. Data centers require constant maintenance. Hard drives fail regularly because there's so many of them, as do processors. Even a very low failure rate results in a single failure every few weeks/days that then needs to have the sled pulled and have the part replaced.

Regarding security, it's only physical security that's good here, simply because it's difficult to get to, but if Starship exists to launch these data centers, it's suddenly also cheap to launch a satellite to go fly up to the rack and hook into the data lines.

[matthewkantar]

So it will be cheap enough that someone can go and break in, but not cheap enough that someone can go and pull/push a few racks once a month?

Compared to other projects they are working on, orbital servers seem like an easy one. Even if they scope in robotic server swaps.If launch was cheap enough it would be attractive. Travel from Boca Chica to LEO would take an hour or two. How long would it take to get to the Sahara?

Originally I was wondering why SpaceX would want to go into a low margin business like server farms, but Amazon has shown that if done well it can be a money volcano.

[Ludus]

There would be greater efficiency of orbital data centers if the data input (as well as power) was coming from orbit already. That might be true if there is a constellation with laser links to Starlink that’s dedicated to 24/7 observation of the whole surface of the earth generating vast amounts of data.

[rsdavis9]

There would be greater efficiency of orbital data centers if the data input (as well as power) was coming from orbit already. That might be true if there is a constellation with laser links to Starlink that’s dedicated to 24/7 observation of the whole surface of the earth generating vast amounts of data.

Not to mention the 24 channels of 4k video from the reality shows on mars
or all the space telescopes
or ...

[AC in NC]

Post #51 should have placed a knife in the heart of this thread.  Don't believe it's at all feasible after reading that.