Technology

Self landing rockets were practically impossible not that long ago

Technically, they still are.

Self driving cars were practically impossible not that long ago.

There have been implementations of a sell-driving vehicle since the 1980s, and we're still far away from "true" full self diving.

Both of these examples demonstrate the adage of "the first 90% of the work takes 10% of the effort, and the last 10% work takes 90% of the effort".

The main factor against it is the $/kg of payload into space.

Oh my lord no. Although, technically yes but not for the reason you think.

The number one issue is heat dissipation. To radiate the heat from one DC satellite (at the power levels needed to run AI workloads) would need a football sized dissipation array. Even if Space X can invent some magical new physics and cut that down to a quarter of that size (hint: they can't), we're still talking about an order of magnitude increase in payload per satellite.

Next on the list is volume. We're currently at around 14k man-made objects in low earth orbit. As it is, satellites (including the ISS) have to perform collision avoidance maneuvers every so often. The calculated limit of satellites we can put up to low earth orbit before orbital collision maneuvers start to become unmanageable is 100k. Basically after that amount we enter into a state where several corrections for each satellite are made regularly, and a single collision at the 100k limit would result in a cascading series of collisions that will render low earth orbit impossible to use. Basically after that anything you put up will get shredded by the insane amounts of debris.

Space X wants to put up a MILLION massive satellites that will require extremely large structures to dissipate the heat from the very power hungry AI chips.

They fully know the impossibility, and when challenged about the over crowding issue during an interview, an engineer brushed it off as "it's not a problem". People who speak that way about science and engineering issues are not serious people.

That’s one of the many issues SpaceX is working to solve, and there’s nothing to suggest they won’t get there.

There are countless engineering and physics reasons why they won't. Stop sniffing Elon's farts. They're not good for your brain.

Edit: all of this is to say: space datacentres are the dumbest idea yet to come out of that idiots face hole. And he's said a lot of really really dumb things.