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Starship V3

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Re: Starship V3

#481

Post by kamaal »

AntiUSAbah wrote: post #348
svantana wrote: post #324

Earlier quoted context omitted.

The joint solar panel + computer system will be pretty close to an ideal black body, which near earth will have an average temperature of about 10°C. And radiation is an issue, but starlink seems to work so I don't see why this wouldn't.

Of course it works, the question is how this would look like and if its financial feasable. You make a H100, ship it to a space dock, load it onto a rocket (rocket requires fuuel, the rocket, etc.) send it up, deploy it, monitor it live 24/7, have means of adjusting its orbit, if it breaks, its immediade full loss, otherwise it will degenerate faster in space than on earth, now it needs a high speed up/downlink to do…

Everything you wrote is some definition of hard, but all doable. None of this is purely in the territory of 'known' impossible(like FTL travel).

Now different people have different points where they quit when things get hard.

This is true for even everyday things in life. Quitting triggers exist for people at various points in the ladder. The end of ladder and path both exist, its upto you to decide if you wish to continue climbing, or give up and quit.

Your mileage may vary.

Re: Starship V3

#482

Post by db48x »

AntiUSAbah wrote: post #348
svantana wrote: post #324

Earlier quoted context omitted.

The joint solar panel + computer system will be pretty close to an ideal black body, which near earth will have an average temperature of about 10°C. And radiation is an issue, but starlink seems to work so I don't see why this wouldn't.

Of course it works, the question is how this would look like and if its financial feasable. You make a H100, ship it to a space dock, load it onto a rocket (rocket requires fuuel, the rocket, etc.) send it up, deploy it, monitor it live 24/7, have means of adjusting its orbit, if it breaks, its immediade full loss, otherwise it will degenerate faster in space than on earth, now it needs a high speed up/downlink to do…

It’s very easy to overestimate the difficulty of cooling things in space, unless you actually run the numbers. So please follow along as Scott Manley runs the numbers: https://www.youtube.com/watch?v=FlQYU3m1e80>.

Basically a Starlink v3 satellite has an estimated power budget of 20kW. Add in the heat absorbed from the environment (both directly from sunlight and reflected off of the Earth) and you’ll find that it must reject about 22kW of heat. That’s a fair amount, but at 65°C it can radiate it all away just using it’s own surface area! No radiator required at all!

Of course the power density of computer racks has been going up over the years. If you want to reach 100kW per satellite then they will need a modest radiator, but nothing extravagant. It would still be smaller than the solar panels, and far smaller than the ones on the ISS. And don’t forget that because radiated heat goes up as the fourth power of temperature, raising the temperature of the system by even a small amount raises the radiation emitted by a lot. If you design the system to run hotter you can minimize the size of the radiator. Most chips these days are designed to max out at 100°C to 110°C without lasting damage, although running them at that temperature 24/7 may reduce their lifespan. There will be some sweet spot in the middle.

And it turns out that a Starlink v3 already has a volume somewhat larger than a 48U rack. You talk about launching 250k satellites in order to have 250k GPUs in orbit, but that’s ridiculous. A real compute swarm will be hundreds or thousands of satellites each equivalent to a whole rack of GPUs.

But you’re not wrong to be skeptical. The economics might not work out even if the cooling is easy enough. It’s just that rejecting the idea takes a lot more than back–of–the–envelope calculations.

Re: Starship V3

#483

Post by NitpickLawyer »

avmich wrote: post #470
arijun wrote: post #270

Earlier quoted context omitted.

> moved a lot of stuff "inside" the engine The level that they managed to fit everything inside of a simple-looking package was so high that the CEO of ULA (the Boeing/Lockheed Martin rocket company) thought they were lying when they first showed pictures [1]. [1] https://www.benzinga.com/news/24/08/40279896/spacex-presiden...

I still don't see TVC there. I think Shotwell was exaggerating.

Here it is, already mounted on Starship - https://i.redd.it/q5dea3tsf60h1.jpeg

Re: Starship V3

#484

Post by db48x »

philipallstar wrote: post #375
svantana wrote: post #326

Earlier quoted context omitted.

How hot do you think black objects in space get? Something like 10°C. Look up thermal equilibrium of an ideal black body.

But are they doing work internally that generates heat? Genuine question.

If you gather 1kW of power from the sun then you have to reject 1kW of heat once you are done with whatever computation you are doing. There’s a bit more heat absorbed from the environment since some sunlight strikes parts of your satellite that are not solar panels, but it’s not too bad. Starlink satellites, just to pick a relevant example, do not need a radiator at all because they stay mostly edge–on to the sun and they can radiate all the heat through their own surface area. The ISS needs big radiators because they want it to be comfortable for humans, but electronics can run significantly hotter than that.

Re: Starship V3

#485

Post by db48x »

le-mark wrote: post #430
damnitbuilds wrote: post #371

Earlier quoted context omitted.

Elon is smart and employs many smart people. If the thermodynamics didn't work, they would know. I do wonder if shielding the multi-billion transistor GPUs will be a difficult.

Just shield them under the tons of heat radiators they’ll be deploying. One ton of compute will > 1 ton of hardware to radiate the waste heat. Does anyone know the multiplier?

The radiators would be a lot smaller than you’d think: https://www.youtube.com/watch?v=FlQYU3m1e80>.

Re: Starship V3

#486

Post by mekdoonggi »

Fordec wrote: post #123

The thing which is seemingly missing from this is their current largest hurdle emerging from the V2 testing. The heat shields keep failing. I guess the focus is going to be on getting stuff up, rather than back down. Thus the Starlink and data center plays, not human space exploration.

From my understanding, they have been intentionally sabotaging the heat shield to test the limits of the ship. They are putting the shield through the ringer to find the extreme boundaries to design around.

If they needed land a payload, they could stuff a dragon capsule in the starship, but the point is building something new.

Re: Starship V3

#487

Post by db48x »

Fordec wrote: post #123

The thing which is seemingly missing from this is their current largest hurdle emerging from the V2 testing. The heat shields keep failing. I guess the focus is going to be on getting stuff up, rather than back down. Thus the Starlink and data center plays, not human space exploration.

I think you’re overstating the problem. All of the tests flown so far were deliberately crippled just to see how much they could get away with. They installed fewer tiles than were really needed, leaving gaps in large surfaces and even leaving the hinge areas of the flaps unprotected. The resulting damage was spectacular and terrible for reusability, but the ships still functioned. That actually bodes well for human spaceflight! Losing a tile crippled the Space Shuttle, but the Starship looks to be much more robust.

Re: Starship V3

#489

Post by bean469 »

inglor_cz wrote: post #248
ivolimmen wrote: post #164

Saw some photo's and the first thing that stands out: the American flag. What's up with that? If you see a product launch in Europe there will be no flag in the photo's (non that I ever saw).

"Europe" does not have a unified stance on this, don't paint our entire continent as The Borg. If you are Dutch, just take a one-hour flight to Copenhagen to see how a city can be absolutely plastered with national flags. If Poland or France were introducing a new nationally produced rocket, they would certainly show their national flags around it as well. They definitely do so when displaying new weapons . So does U…

Yeah, but this is not a national project, but a private one

Re: Starship V3

#490

Post by AntiUSAbah »

db48x wrote: post #482
AntiUSAbah wrote: post #348

Earlier quoted context omitted.

Of course it works, the question is how this would look like and if its financial feasable. You make a H100, ship it to a space dock, load it onto a rocket (rocket requires fuuel, the rocket, etc.) send it up, deploy it, monitor it live 24/7, have means of adjusting its orbit, if it breaks, its immediade full loss, otherwise it will degenerate faster in space than on earth, now it needs a high speed up/downlink to do…

It’s very easy to overestimate the difficulty of cooling things in space, unless you actually run the numbers. So please follow along as Scott Manley runs the numbers: https://www.youtube.com/watch?v=FlQYU3m1e80 >. Basically a Starlink v3 satellite has an estimated power budget of 20kW. Add in the heat absorbed from the environment (both directly from sunlight and reflected off of the Earth) and you’ll find that it m…

I'm not rejecting the basic idea in itself. There is nothing in this idea which we as humans can't do today. No issues here. Its just so much more expensive than just doing it in a dessert and putting fibre and solar panels and batteries there.

The Starlink v3 doesn't exist yet in space, it also needs Starship apparently and Musk said it will have the size of a Boeing 737 fully deployed. So it will not be small and its not proofen yet.

A rack with 48u will either have 12 or 24 GPUs which equals to 9kW or 17kW. Than its not 250k satellites for a 'small' 300MW DC but only 25k. Still a very crazy number.

I would love to see all of this scifi stuff happening. Spaceship in space, travel gates, dyson sphere but there is just no current breakthrough in our society which would indicate that this makes sense.

In my opinion, we as a society will have to get rid of capitalism first before we will do the next step and just because Musk needs a story to sell to keep his construct alive, doesn't mean its the right time.

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