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Comment Re:Catastrophic man-made global warming (Score 2) 274

Perhaps, perhaps not. Venus is still very poorly understood. In its high temperature environment its conditions are largely self-sustaining (preventing the sequestration of CO2 in rock), although it's also unstable, prone to broad temperature and pressure swings. It also appears to have undergone a global resurfacing event about 300-500mya, if that gives a clue as to how unstable the planet as a whole is. ;) We don't know what caused it, or really anything about it. Part of the planet's properties are now a result of it having lost its water rather than being a cause, such as its hard crust. Obviously its lack of a magnetic field is responsible for its loss of water, but we don't know exactly when or why it disappeared (there are of course theories... I had always just assumed it was the slow rotation rate, but the last research I read suggested that not enough to account for it). Other issues as to how Venus ended up as it did may be related to size - although it's only a bit smaller than Earth, that may be the initial factor that set its fate in motion - for example, its lithosphere in general appears to be thicker and higher viscosity on Earth, which could have hindered or prevented plate tectonics, and thus subduction of carbonates.

Either way, it's a mess now at the surface (though rather comfy ~55km up ;) ). And I'm not so sure I buy into some of the proposed ways to fix it (terraforming). For example, some have suggest mass drivers ejecting the atmosphere. Let's just say you can pull it off, and then you start building oxygen in the atmosphere - what happens next? The crust is something like 7-9% FEO; it's going to rust away whatever oxygen you make in short order.

Interestingly, I'd argue that this is possibly the salvation to Sagan's airborne-microbe concept for terraforming Venus. The main criticism is that if you engineered some sort of carbon-sequestering microbe on Venus (or artificial equivalent), you'd end up with a deep surface layer of graphite surrounded by some hugely hot, dense oxygen layer, and the atmosphere would explode. But that would never happen; at Venus surface temperatures and pressures, the surface rocks would rust away the oxygen as fast as it was created, even in tiny quantities, with the wind blowing the dust around to collect at low/eddy areas. So you're laying down bands of carbon and iron oxide as you burn through the planet's iron buffer. Where have we seen this before? Right, Earth, ~2,3 billion years ago, banded iron formations. Just like on Earth, you'd eventually burn through the iron and start to accumulate oxygen. But by then the graphite is already underground, buried in iron dust.

It's not a fast process. But it has precedent. Microbes already rusted at least one planet, and that planet's surface conditions weren't nearly as favorable for rusting as Venus's.

Comment Re:Catastrophic man-made global warming (Score 1, Troll) 274

I don't know how China managed to melt so much arctic ice, leading to the absurd situation that just a couple days before the winter solstice this year I went on a hike through the snowless mountains in Iceland among chirping songbirds digging for worms. All I have to say to China about this is: Best. Conspiracy. Ever. Well played, China. Well played.

Businesses

Tesla Is Investing $350 Million In Its Gigafactory, Hiring Hundreds of Workers (cnbc.com) 124

Just weeks after the massive Gigafactory started producing batteries, Tesla has announced plans to hire more workers and use the facility to make the motor and gearbox for its upcoming Model 3 electric sedan. CNBC reports: Tesla will invest $350 million for the project, and hire an additional 550 people, according to the governor's comments. That will be over and above the company's existing commitment to hiring 6,500 people at the Gigafactory, according to comments made by Steve Hill, the director of the governor's Office of Economic Development, to Nevada newspaper the Nevada Appeal. Tesla CEO Elon Musk has made manufacturing efficiency a high priority for the company, but Tesla will require a lot of factory floor to meet its goal of to pumping out 500,000 cars by the end of 2018, and then making one million cars by 2020. Meanwhile, the city of Fremont recently approved Tesla's application for an additional 4.6 million square feet of space there.

Comment Re:News from other countries... (Score 2) 45

Well, when it comes to space budgets....

NASA: $19,3B
ESA: $5,8B
Roscosmos: ~$2B/yr
JAXA: $2,0B
CNSA: $0,5B official / $1,3B est.
ISRO: $1,2B

It's not just US bias that leads to most stories coming from NASA. NASA really does spend the most on space research and exploration, by large margins.

Still, the public perception is that NASA's budget is far more than it actually is.

Submission + - Law for Autonomous Vehicles: Supporting an Aftermarket for Driving Computers (perens.com)

Bruce Perens writes: How will we buy self-driving cars, and how will we keep them running as self-driving software and hardware becomes obsolete much more rapidly than the vehicle itself? Boalt Hall legal professor Lothar Determann and Open Source Evangelist Bruce Perens are publishing an article in the prestigious Berkeley Technology Law Journal on how the law and markets might support an aftermarket for self-driving computers, rather than having the manufacturer lock them down or sell driving as a service rather than selling cars. The preprint is available to read now, and discusses how an Open Car, based on Open Standards and an Open Market, but not necessarily Open Source, can drive prices down and quality up over non-competitive manufacturer lock-in.

Comment Re:IT is amazing (Score 5, Insightful) 99

Most folks drink stale coffee. Try roasting your own (I use Sweet Maria's for supplies) or going somewhere with a roaster on site who is honest enough to tell you the roast date. It should be from 2 to 10 days ago. Flavor development in coffee is a rancidification process. Like cheese, you want to catch it when it is a little, but not too, rancid.

Comment Re:...Or Just Take Aspirin. (Score 2) 99

Let's not forget the effect of helicobacter pylori bacteria on ulcers, they are in general held to be the main cause these days.

I have another theory about the beneficial effect of aspirin, caffine, etc. We evolved with them. Our diet was rich in salycilates and chemicals similar to theobromine or caffine. They came from the plants we ate, some of which were mildly toxic and which we evolved to process to the point that we became dependent on some of their effects. There are a lot of things in the primitive diet that modern people don't eat much at all, like acorns which had to be soaked to remove alkalai and tannin.

If this is the case, taking aspirin and drinking coffee or tea replace substances found in a more primitive diet.

Comment Re: Note that what's large... (Score 4, Informative) 84

Venus has multiple "tropopauses" and "stratospheres", depending on how you define them. The atmosphere is like a layer cake with multiple convection zones (like Earth's troposphere) separated by areas of dynamic stability (like Earth's stratosphere). And again, ~50-70km is an awfullly long way from the surface, and surface winds are weak. But, there's a lot about Venus that we don't understand.

Comment Note that what's large... (Score 3, Informative) 84

.... is the size, not the intensity. The air moves only slightly faster or slower than the surrounding atmosphere as one passes through the wave.

They weren't expected on Venus, though. Venus's surface is dozens of kilometers down, thick and "soupy" there, transitioning to thinner layers above. It was surprising to see that surface features that far away, in a fluid that can compress, would still make clear phenomena like gravity waves in the high atmosphere.

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