And whether you can radiate all that heat in the vacuum of space

If orbital compute fails, it won't be due to heat issues. Current radiators are around 8kg per square meter, and each square meter can radiate close to 1kW. So a 1 megawatt satellite would need less than 40 square meters of radiators weighing around 300kg. And that assumes there won't be any improvements in radiator efficiency.

The outcome is almost entirely determined by launch costs.

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UltraSane 4 hours ago | parent [-]

You need both enormous solar panels and radiator panels. 1MW needs about 7000 square meters of solar panels. This would require 1,500 square meters of radiator panels along with a lot of coolant pipes that have to be kept edge on to the sun at all times. And all of this will require thousands of kilograms of structural support.

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ggreer 4 hours ago | parent [-]

What sort of solar panel gets only 140 watts per square meter in space? Even with efficiency as low as 20%, you'd get 1 megawatt from 3,700 square meters. And you'd design the satellite to minimize heat transfer between the panels and main body, because panels can run at higher temperatures than the computers. Since heat radiation goes up with the 4th power of temperature, the panels would not need large radiators. In most satellites today, a coating on the back of the panel is all that is required.

Edit: Oh wait, you're the guy who makes bold claims and then refuses to bet on them because you know you'll lose money. 10 months ago you said, "no Tesla has EVER driven without a driver with Tesla assuming liability for crashes. And I don't think they ever will."[1] When I tried to get you to bet money on your prediction (which is now false), you ignored me. A few months later, you said, "Tesla doesn't even have the permits to operate Robotaxis in California and probably never will because they are actually stricter vs Texas."[2] and again I tried to bet you that Tesla would have Robotaxis in California before the end of 2028, and again you refused.

I really wish HN had a way to mark or mute users, because if I knew who I was replying to, I'd collapse the thread and not waste my time engaging with you.

1. https://news.ycombinator.com/item?id=45661368

2. https://news.ycombinator.com/item?id=47816921

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UltraSane 3 hours ago | parent [-]

That includes overprovisioning for times the satellite is behind the earth.

And the Tesla robotaxi is still a embarrassing failure.

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ggreer 3 hours ago | parent [-]

I'm sorry, but you do not know what you are talking about. If you'd read the Starcloud white paper I linked to, you'd see that the plan is to put satellites in a dawn-dusk sun-synchronous orbit, meaning they would be in constant sunlight and the backs of the solar panels would radiate to deep space. No orbital compute project is planning to put satellites in an orbit where Earth blocks the sun, as that would require large battery banks to power the computers while in shadow.

	▲	piloto_ciego 2 hours ago \| parent [-]
		This is the correct take here. SSO is where they'll park these things.