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> but there’s no real way to coordinate that in society from the top down without being authoritarian.

PR comes to mind. They managed to convince millions of people that smoking is 'cool', we just need another Bernays to do the same for having kids.


Are you a LLM?

No, just a 9front user with a web browser, Netsurf. I shouldn't need JS to read an article you know.

You often have a radio clock source like DCF77 that all those radio controlled clocks use

Quake and Doom sure come to mind

C is not a subset of C++, there are some subtle things you can do in C that are not valid C++

It is when compared with C89, also the ISO C++ requires inclusion of ISO C standard library.

The differences are the usual that occur with guest languages, in this case the origin being UNIX and C at Bell Labs, eventually each platform goes its own merry way and compatibility slowly falls apart with newer versions.

In regards to C89 the main differences are struct and unions naming rules, () means void instead of anything goes, ?: precedent rules, implicit casts scenarios are reduced like from void pointers.


Some subtle and some not so subtle.

Same that happens with Starlink satellites that are obsolete or exhausted their fuel - they burn up in the atmosphere.

> You could argue that it doesn't really count though because it was only turing complete in theory

Then you have to also count the Z3 which predates the Colossus by 2 years.

[1] https://en.wikipedia.org/wiki/Z3_(computer)


But there are no clouds in space and with the right orbit they are always facing the sun

You know how people sometimes dismiss PV by saying "what happens at night or in cloudy weather?"?

Well, what happens over the course of a year of night and clouds is that 1 TW-peak becomes an average of about 110 to 160 GW.

We're making ~1 TW-peak per year of PV right now.


but then you have answered the earlier question: solar panels in space pay themselves back ~7-8 times faster

That wasn't the original question. The head of this thread was quoting Musk's claim, which I repeat here:

> it is possible to put 500 to 1000 TW/year of AI satellites into deep space

This is 500-1000 times as much as current global production.

Musk is talking about building on the Moon 500-1000 times as much factory capacity as currently exists in aggregate across all of Earth, and launching the products electromagnetically.

Given how long PV modules last, that much per year is enough to keep all of Earth's land area paved with contiguous PV. PV doesn't last as long in space, but likewise the Moon would be totally tiled in PV (and much darker as a consequence) at this production rate.

In fact, given it does tile the moon, I suspect Musk may have started from "tile moon with PV" and estimated the maximum productive output of that power supply being used to make more PV.

I mean, don't get me wrong, in the *long term* I buy that. It's just that by "long term" I mean Musk's likely to have buried (given him, in a cryogenic tube) for decades by the time that happens.

Even being optimistic, given the lack of literally any experience building a factory up there and how our lunar mining experience is little more than a dozen people and a handful of rovers picking up interesting looking rocks, versus given how much experience we need down here to get things right, even Musk's organisation skills and ability to enthuse people and raise capital has limits. But these are timescales where those skills don't last (even if he resolves his political toxicity that currently means the next Democrat administration will hate his guts and do what they can to remove most of his power), because he will have died of old age.


I wasn't referencing Elon's claim, but your reply to

> In fairness, solar cells can be about 5x more efficient in space (irradiance, uptime).

Clearly this person was referencing a financial efficiency predominantly through uptime.

Your other points: I agree :)


> Clearly this person was referencing a financial efficiency predominantly through uptime.

I read the person you are quoting differently, as them misunderstanding and thinking that the current 1 TW-peak/year manufacturing was 1 TW-after-capacity-factor-losses/year.


The 1TW is the rated peak power output. It's essentially the same in space. The thing that changes is the average fraction of this sustained over time (due to day/night/seasons/atmosphere, or the lack of all of the above).

It's still the same 1TW theoretical peak in space, it's just that you can actually use close to that full capacity all the time, whereas on earth you'd need to over-provision substantially and add storage, so 1TW of panels can only drive perhaps a few hundred GW of average load.


> the whole capacity

Wouldn’t something like half of the panels be in shadow at any time?


Depends where you put them. The current vogue option is a sun-synchronous orbit: https://en.wikipedia.org/wiki/Sun-synchronous_orbit

polar orbit

That's the price before Starship which would be the prerequisite for this whole project.

Yes, and as we know Starship will be doing regular commercial launches starting in 2020, maybe 2021.

We're getting close to having the time for Starship's delays to be the same as the actual time for the Saturn 5 to go from plans to manned launches (Jan 1962-Dec 1968).


Are you trying to say it'll be delayed or that it'll never work?

One is obviously true, and the other is very likely false.


It’s hard to estimate what Starship’s actual costs will be when it isn’t fully operational. I am finding estimates of $100 to $200 per kilogram and even as low as $10 per kilogram.

Let’s say the costs in 5 years do get as low as $15 per kilogram or about 2 orders of magnitude improvement in launch prices. That means a 200-ton payload Starship would cost $3,000 to launch.

Do you honestly believe that? The world’s largest rocket cost a total of $3,000 to launch?


> Let’s say the costs in 5 years do get as low as $15 per kilogram or about 2 orders of magnitude improvement in launch prices. That means a 200-ton payload Starship would cost $3,000 to launch. Do you honestly believe that? The world’s largest rocket cost a total of $3,000 to launch?

You have missed three zeroes in this calculation ;)

15 per kg for a 200-ton payload is about 3 million$. That seems achievable, given that propellant costs are about 1-1.5 million.


Ah yeah. 200 tons is 200,000 kilograms. Definitely way off there. That is an incredulous number.

"it'll never work" is quite black and white while "failure" is a lot more of a grey area. Will it actually launch? Sure, we've seen it. Will it actually hit the reliability as sold? Will it have as fast of turnaround time to reach launch timing goals? Can it actually launch as much payload as promised? Will the economics actually shake out as intended?

Did the Cybertruck "never work"? Obviously not, they're on the streets. Was it a <$40k truck with >250mi range? No.

Did FSD "never work"? Obviously not, tons of people drive many, many miles without touching the wheel. Does Tesla feel confident in it enough to not require safety operators to follow it on robotaxi trips? No. Does Tesla trust it enough to operate in the Las Vegas Loop? No. Has Tesla managed to get any state to allow it to operate truly autonomously? No.

Look, I hope Starship does work as advertised. Its cool stuff. But I don't see it as a given that it will. And given by the track record of the guy who promised it, it gives even less confidence. I'm sad there's less competition in this space. We have so many billionaires out there and yet so few out there actually willing push envelopes.


One reliable method of pushing envelopes, attracting investment and hiring smart people is to get excited about unrealistic timelines.

The best case is you meed the unrealistic timeline, the average case outcome is you solve the problem but it is delayed several years. And the worst case is it fails and investors lose some money.

If you try to hire people but your message is: we want to reduce the cost of access to space by 20% in thirty years, you are going to get approximately zero competent engineers, and a whole lot of coasters.

And no investors, so you'll be dependent on the government anyway. Depending on the government is great until people you do not agree with or are generally anti science, are in power. I assume this part should not need an example nowadays?


> One reliable method of pushing envelopes, attracting investment and hiring smart people is to get excited about unrealistic timelines.

Its also a good way to shred morale and investor confidence when you're a decade past your timelines or continue to fail on actually delivering on past promises.


You'd think so, but if you bet on this guy not being able to get investors you'll end up being wrong.

It doesn't make sense (neither does Tesla's valuation, for example), but it is what it is.

Both Spacex and Xai have investors lining up.


Latency isn't an issue with Starlink - the data centers are in low earth orbit, not in GEO

given the max bandwidth of a starlink sat is in the 100Gb on a good day range why would you want to limit a DC to less bandwidth than a single cheap fibre?

Also in LEO you're going to have reentry become more of an issue (starlink burning up in the atmosphere isn't some free garbage removal it will have a measurable impact on the chemical make up (assuming it even burns up and doesn't just squash more farm buildings), Power supply more of an issue and still have huge problems with heat and radiation.


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