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Comment Re:Misguided priorities for sure (Score 1) 209

Radios are everywhere

One could probably find a radio, but then you have to keep yourself in proximity to said radio. That is, if your most readily-accessible radio is in your car, it's bloody inconvenient to sit in the car just to listen to the radio (assuming you're not actively driving somewhere - sheltering in place). Restaurants, offices, ..., sure, they may have a radio, but you take it with you to go somewhere else? One person probably could, assuming it could be run on batteries, but that one person is probably not you.

The beauty of unlocking the capability of your smartphone is that you are likely to have it on your person a lot of the time, and it is trivial to take with you.

Comment Talent well utilized (Score 1) 102

and to think, these engineers could have been spending their time doing something so mundane and pointless, like saving the world or improving everyday peoples' lives. Instead, the beneficent forward thinkers at McDonalds have showered upon them the blessing of using their extraordinary abilities and scarce resources to design a straw!

Comment Re: Well, once the panels are installed (Score 4, Informative) 415

$5K of coal is in the timezone of 725MW-hr

Since you haven't provided any links to back your data, I have to ask: is that energy value just a conversion of the raw BTUs, or into electricity delivered to end users. It's a really important difference, since most coal plants are only 25-35% efficient in creating electricity from raw heat. If you are quoting the raw energy content as heat, then I'd argue you need to discount it by a factor of 3-4x, since most coal is burned to make electricity, and PV creates electricity directly.

Here's another approach: the wholesale price for electricity is, depending on the region, something like $25-50/MWh [source]. Unfortunately, the breakdown doesn't tell us the cost for each source (coal, nuke, gas, etc.), but let's argue that it's on the low end: $25/MWh. That captures the cost not only of the fuel, but also the operating costs of the plant, profit, paying off the loans to build the plant, etc. On the other hand, a large pile of coal is pretty useless for generating electricity without all the rest of those costs, so I'd say it's fair to include them.

At $25/MWh, a $5k purchase would get you 200 MWh of electricity, which makes PV look much more favorable.

Submission + - Actor John Hurt dies at age 77

necro81 writes: A fantastic chameleon of the stage and screen has died. Sir John Hurt passed away at age 77 today. Slashdot readers should recognize him as the first person to have a xenomorph burst from his chest in the original Alien (a scene he later parodied in Spaceballs . Others may recall he played the downtrodden protagonist Winston Smith in the film adaption of 1984 , then later played the tyrannical High Chancellor in V for Vendetta . Also: the titular character in The Elephant Man, Caligula in I, Claudius, Ollivander in the Harry Potter films and, more recently, Gilliam in Snowpiercer. But his career spanned decades and genres, and our world is a bit meeker and colorless without him.

Comment Shockingly close, actually (Score 4, Insightful) 139

The thing that blows my mind is not that one measurement is higher and another lower, it's just how closely they agree: to less than 10%. This despite the fact that they were arrived at from different instruments and lines of inquiry. The earlier measurement from Planck satellite measurements is derived from measurements of cosmic background radiation. The newer measurement comes from images of gravitational lensing of distant quasars, from the Hubble and Spitzer telescopes. For such a tricky measurements, and such an abstruse topic, I wouldn't have been surprised if they differed by an order of magnitude.* And yet, the agree pretty closely.

Science is really freaking awesome. Sure, assuming that the expansion is universal and constant (i.e., there is only one value for the Hubble Constant, which is hardly a sure thing), you ought to be able to measure the same answer by any experiment designed to measure it, within the experimental error. I ought to arrive at the same value for the gravitational constant, too, whether I experiment using a precision pendulum, or dropping a cannonball from the tower of Pisa (accounting for air friction, of course), or analyze the tides, or by successfully putting a man on the Moon. It doesn't matter who I am, or where I live, or under which government, or what language(s) I speak - it all still works.

* Hubble's own initial estimate was about 10x the current values. For those that are interested, here's a graph of the value of H0, with error bars, through history. [source]

Comment Re: Contrast this with the incoming administration (Score 1) 333

At this point his tax returns are as irrelevant as Obama's birth certificate, or college records were after he had been elected

But we did get those records, didn't we? Whereas we're still waiting for, and probably never will receive short of a subpoena, Trump's tax records. And there is a significant difference in relevance between the tax returns and Obama's records: Trump's records can tell us some very important things about the present that we don't already know, whereas Obama's records only show interesting tidbits about the past, and didn't tell us anything that we didn't already know.

Comment Re:Guess I just never paid attention (Score 1) 201

Anyone with a basic understanding of circuitry can make a series-parallel array of cells for whatever current draw and voltage requirements you can imagine. Keeping it cool is simple, airflow and aluminum battery casings are the answer.

If your only goal is to pump out power, then yes, most anyone with some basic knowledge can do it.

If, however, you want to make a reliable and safe product that can last for years with predictable behavior, replicate it 100,000 times at reasonably cost, then stuff it into an automobile to let any joe-shmo use it, it's a whole hell of a lot harder. That takes uncommon knowledge, skill, and experience, a whole hell of a lot of money, and a tremendous comfort with risk.

For anyone who is interested, here is a 2014 teardown of a Model S battery pack. It's pretty awesome stuff, and clearly a lot of careful thought and design went into it. Incidentally, the pack is not thermoregulated* using airflow - it has tubing with circulated coolant.

* For Li-Ion chemistry, it's not merely a matter of keeping the cells cool; keeping them at a uniform temperature across the pack is far more important for avoiding accelerated aging and catastrophic failure

Comment Re:And NEOCam is on Life Support (Score 2) 86

I was under the impression that setting off a nuke on an impactor only works in movies. In reality there is no atmosphere, therefore almost no shockwave, and the object continues approaching on the same vector and with the same mass.

The people who developed Project Orion would beg to differ. A nuclear blast in proximity to a solid object can definitely provide impulse.

Comment Re:"Low-cost planetary missions" (Score 0) 86

Who actually thinks NASA will thrive under Donald fucking Trump? LOL.

I could see Trump being an enthusiastic supporter of manned spaceflight. Because, ya know, back during the mythic time that America was great, we landed on the fucking moon. "It was a beautiful moon; a 'uuuuge moment for our country. America will never be Great Again (tm) so long as we're doing laps in a tin can. And can you believe this - the space station was made in Taiwan. We need to go back to the Moon, bigly."

But the arguably more important (and higher-ROI) science and basic research that NASA works on? Shit, man, Trump has no use for knowledge, he's already smarter than everyone else. If anything I learned from the campaign, the President-elect hasn't a shred of intellectual curiosity in him, nor the humility to acknowledge that he doesn't actually know everything. He's finally in a position to stick it to the eggheads that made him look bad back in school.

Comment No formal chain of command here (Score 1) 488

"We're all good friends here. Equals among peers. You guys are awesome, and I have tremendous respect for what you guys are doing. Except that Jack Dorsey, what an asshole! Sad!"

This is all very congenial and friendly. But how much you want to bet that, if there is ever a public disagreement between these companies and Trump, he'll suddenly decide that the non-existent chain of command is going to suddenly turn into a twitter barrage along the lines of "do it my way, you big meanies!"

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Things are not as simple as they seems at first. - Edward Thorp