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Comment I agree (Score 4, Insightful) 78

Yes AI may be generating a lot of code now. But you need someone to find where what was generated was weak, or inefficient.

Over time the quality of generated stuff will improve, but since so many companies are generating a lot of code today that is a LOT of technical debt that is building up rapidly.

I especially agree that now is the time to round out your skills - as stated, study design, study platforms you connect to but do not develop on. Study AI tools, find out when they work for things you work on and know well - and when they do not.

Good luck out there everyone!

Comment Re:Time to resurrect the old meme... (Score 4, Insightful) 213

Just to add some insight:

Trump, in a Truth Social post, said: “We require a commitment from these Countries that they will neither create a new BRICS Currency, nor back any other Currency to replace the mighty U.S. Dollar or, they will face 100% Tariffs, and should expect to say goodbye to selling into the wonderful U.S. Economy.”

https://apnews.com/article/tru...

So clueless.

The fact is that the trade imbalance is the largest single factor that makes the US dollar the world currency -- and also helps to keep the federal debt cheap. All of those countries that have a trade surplus with us send us lots of goods and in exchange they get lots of dollars. What do they do with them? They buy US-denominated securities, including treasury bonds. So many people and organizations around the world holding large reserves of US-denominated securities is what makes the dollar the world's default currency.

To the extent that he succeeds at "correcting" the trade imbalance, he'll undermine the dollar's status. And trying to bully countries into sticking with the dollar by threatening action that will make the dollar worth less to them is just... clueless. And that's assuming his actions to explode the debt while escalating financing costs doesn't result in enormous devaluation of the dollar, which would make it worthless rather than just worth less.

On balance I think I'm mostly glad that Trump is a moron, because if he weren't he would be really dangerous. On the other hand, if he had either a brain or the humility to listen to people who do, he might understand that he's trying to destroy what he's trying to control, and that winning that sort of game is losing. Probably not, though. He's amoral enough to be okay with ruling over a relative wasteland, because he and his will be better off.

Comment Re: Talking about the weather (Score 1) 149

Sure, itâ(TM)s quite possible for two people to exchange offhand remarks about the local weather apropos of nothing, with no broader point in mind. It happens all the time, even, I suppose, right in the middle of a discussion of the impact of climate change on the very parameters they were discussing.

Comment Re:Erm... (Score 1) 163

t takes between 150 kWh and 800 kWh to separate and liquify a ton of oxygen, so if you're paying $0.10 per kWh, LOX costs $15-80 per ton

It occurs to me that this is a good use of massive solar plants. It wouldn't cost much to idle your oxygen-separation equipment when the sun isn't shining, so you wouldn't need much in the way of battery storage. Grid scale solar without battery backup in a sunny area (like south Texas) can cost as little as $0.03/kWh, which would give you a separation cost of $4.5 to $24 per ton of LOX. Obviously, if you were producing LOX at a scale needed to fuel a fleet of Starships, you'd work to get that towards the bottom of the scale -- so the LOX loadout for a ship could cost on the order of 3500 * 4.5 = $15,750. To launch 150 tons to orbit. Of course you still need methane.

Could you make "green" methane (i.e. without using fossil fuels) with a big solar farm, and what would that cost? You'd do it with the Sabatier reaction to combine CO2 and H2 to get CH4. To make a ton of CH4 you need 2.75 tons of CO2 and 0.5 tons of H2 (stochiometry, dawg). To get a ton of CO2 with direct air capture takes about 2000 kWh of electricity, so 5500 kWh for the CO2. At $0.03/kWh that's $165 for the CO2. However, producing the half-ton of H2 with electrolysis would take 25,000 kWh, so $750. This puts the raw materials cost of green CH4 at around $915. The Sabatier reaction would add a little more, call it $930 in all.

So... Starship could be entirely solar-powered at a cost of around 3500 * 4.5 + 1000 * 930 = ~$946k, assuming $.03/kWh, ignoring equipment and storage overhead. It turns out that the cost is utterly dominated by the cost of methane production; LOX is all but free. But the cost of solar will likely continue to go down so... fuel costs could indeed get really, really low, even with a zero-carbon strategy. Perhaps as low as $2/kg to LEO.

Comment Re:I live (Score 4, Interesting) 149

The thing to understand is we're talking about sixth tenths of a degree warming since 1990, when averaged over *the entire globe* for the *entire year*. If the change were actually distributed that way -- evenly everywhere over the whole year -- nobody would notice any change whatsoever; there would be no natural system disruption. The temperature rise would be nearly impossible to detect against the natural background variation.

That's the thinking of people who point out that the weather outside their doors is unusually cool despite global warming. And if that was what climate change models actually predicted, they'd be right. But that's not what the models predict. They predict a patchwork of some places experiencing unusual heat while others experience unusual coolness, a patchwork that is constantly shifting over time. Only when you do the massive statistical work of averaging *everywhere, all the time* out over the course of the year does it manifest unambiguously as "warming".

In the short term -- over the course of the coming decade for example, -- it's less misleading to think of the troposphere becoming more *energetic*. When you consider six tenths of a degree increase across the roughly 10^18 kg of the troposphere, that is as vast, almost unthinkable amount of energy increase. Note that this also accompanied by a *cooling* of the stratosphere. Together these produce a a series of extreme weather events, both extreme heat *and* extreme cold, that aggregated into an average increase that's meaningless as a predictor of what any location experiences at any point in time.

Comment Re:Erm... (Score 2) 163

It will never cost that little. A Falcon 9 has about 400 tons of propellant. If it were all commercial diesel, it would cost $400,000, or $17 per kg of weight launched to LEO. But of course it's not commercial diesel. Liquid oxygen and RP1 are both much more expensive.

Starship burns methane, not RP1.

Between SuperHeavy and Starship, a fully-loaded stack needs 3500 tons of LOX and 1000 tons of CH4. So what do those cost?

Well, oxygen is easy to get from the atmosphere, so the cost of LOX is really just some equipment (which isn't terribly expensive to buy and maintain) plus electricity, and the cost ends up being dominated by the cost of electricity. It takes between 150 kWh and 800 kWh to separate and liquify a ton of oxygen, so if you're paying $0.10 per kWh, LOX costs $15-80 per ton. There are some other costs to handle and store it, so let's say $100/ton.

CH4 can be created many ways. The cheapest is probably to purify natural gas, which costs about $190 per ton (that site shows ~$5 per 1000 ft^3, and a ton is 38k ft^3). Add some costs for purification and cooling, so call it $250/ton.

3500 tons LOX * $100/ton + 1000 tons CH4 * 250/ton = $600k. Musk usually calls it $1M, which seems pretty reasonable, since they're probably not separating/purifiying it themselves and there transportation costs. 150 tons of payload to LEO with $1M worth of fuel means the fuel-only cost is $6.67/kg.

Comment Re:Erm... (Score 1) 163

we have enough accumulated knowledge that just getting to orbit shouldn't be accompanied by a string of failures like Starship has been having

Nonsense. Our only experience with reusable orbital rockets is the space shuttle, which was an unsustainably-expensive and complex beast that was more refurbishable than reusable and had a payload one fifth of what Starship is designed for. It's all of the differences that aim to make Starship both reusable and cheap that make it hard. It's possible that it's just too ambitious, that we don't yet have the technology to make a cheap, fully-reusable (not refurbishable, reusable) orbital rocket with massive capacity. No one else has done it... no one else is even trying, that's how hard it is.

Failure is expected. If they managed to launch and land both Starship and SuperHeavy in less than a dozen test flights, that would be the surprise.

Comment Re:Raise your hand if you're surprised (Score 1) 209

Between all the permafrost melting across Russia to methane to massive fossil fuel use, how can anybody be surprised? I have long viewed the worst possibilities as the most likely. The most likely predictions always seemed pretty damn optimistic. We fucked.

I'm surprised, and you should be too, if your view is evidence-based, because this is a new effect that was not predicted by any of the previous models, which already consider the melting permafrost, methane emissions and fossil fuel use.

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