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Comment Re:I live (Score 2) 130

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 Not all jobs are like that. (Score 1) 52

Office jobs are not the only jobs, but they're the easiest to outsource.

Consider doing something whole nations worth of other humans aren't competing to do. I've never lacked job offers even in retirement because I don't seek to compete with everyone else. I avoid them instead, doing things which require me onsite to personally interact with the systems (aircraft, industrial equipment maintenance etc). Experience matters when ones interactions are more demanding than just a keyboard and mouse.

I get that physically effortless office work is desirable but the point of work is reasonably secure income including resistance to outsourcing. If you're not getting hired at what you wish you were great at, consider a job with less desperate competition.

Comment Re:Erm... (Score 2) 141

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) 141

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.

Submission + - How robotic hives and AI are lowering the risk of bee colony collapse (phys.org)

alternative_right writes: The unit—dubbed a BeeHome—is an industrial upgrade from the standard wooden beehives, all clad in white metal and solar panels. Inside sits a high-tech scanner and robotic arm powered by artificial intelligence. Roughly 300,000 of these units are in use across the U.S., scattered across fields of almond, canola, pistachios and other crops that require pollination to grow.

AI and robotics are able to replace "90% of what a beekeeper would do in the field," said Beewise Chief Executive Officer and co-founder Saar Safra. The question is whether beekeepers are willing to switch out what's been tried and true equipment.

Submission + - Study finds online searches reduce diversity of group brainstorming ideas (phys.org)

alternative_right writes: While the study found no statistically relevant difference between the creativity of individuals with access to internet search and those without, as those individuals were clumped into groups, internet search appeared to stymie their production of ideas.

"This appears to be due to the fact that Google users came up with the same common answers, often in the same order, as they relied on Google, while non-Google users came up with more distinct answers," wrote lead author Danny Oppenheimer, a professor in CMU's Department of Social and Decision Sciences.

Submission + - NASA teams with Netflix to stream rocket launches and spacewalks this summer (nerds.xyz)

BrianFagioli writes: NASA is coming to Netflix. No, not a drama or sci-fi reboot. The space agency is actually bringing real rocket launches, astronaut spacewalks, and even views of Earth from space directly to your favorite streaming service.

Starting this summer, NASA+ will be available on Netflix, giving the space-curious a front-row seat to live mission coverage and other programming. The space agency is hoping this move helps it connect with a much bigger audience, and considering Netflix reaches over 700 million people, that’s not a stretch.

This partnership is about accessibility. NASA already offers NASA+ for free, without ads, through its app and website. But now it’s going where the eyeballs are. If people won’t come to the space agency, the space agency will come to them.

Comment Re:Raise your hand if you're surprised (Score 1) 195

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.

Submission + - Space is hard (spacenews.com)

RUs1729 writes: For-profit companies are pushing the narrative that they can do space inexpensively. Their track record reveals otherwise: cutting corners won't do it for the foreseeable future.

Submission + - DoJ deal gives HPE the go-ahead for its $14 billion Juniper purchase (telecoms.com)

AmiMoJo writes: HPE has settled its antitrust case with the US Department of Justice (DoJ), paving the way for its acquisition of rival kit maker Juniper Networks. Under the agreement, HPE has agreed to divest its Instant On unit, which sells a range of enterprise-grade Wi-Fi networking equipment for campus and branch deployments. It has also agreed to license Juniper's Mist AIOps source code – a software suite that enables AI-based network automation and management. HPE can live with that, since its primary motivation for buying Juniper is to improve its prospects in an IT networking market dominated by Cisco, where others like Arista and increasingly Nokia and Nvidia are also trying to make inroads.

Comment: Pour one out for Juniper.

Submission + - Defense Department to stop sharing satellite weather data. (npr.org)

Dustin Destree writes: Maybe it's conspiracy theory, maybe it's connected, but I remember something about AccuWeather wanting this to happen so only they could get the data, and then sell it to others. No more hurricane data, and it'll be so much easier to deny climate change when you can no longer see the sea ice retreating, or can't afford (if they sell it) access to the data proving so!

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