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Comment: Re:I'll believe it when I see it... (Score 1) 116

by Rei (#49767671) Attached to: India Ends Russian Space Partnership and Will Land On the Moon Alone

Its not that simple. You can't just recover it from nuclear reactor waste because it's mixed in with other isotopes of plutonium, and isn't in that great of quantities to begin with. So first off you have to reprocess nuclear waste to extract the neptunium - which again, itself isn't in very great quantities, it takes a lot of waste, and most places don't want to do waste reprocessing to begin with due to cost and liability issues. You then have to make neptunium targets and expose them to a neutron flux - that is, using neutronicity that could otherwise be used for power generation or other valuable purposes (it takes a lot of neutrons to make a tiny bit of Pu238). Pu238 should be more thought of as a manufactured product than as a byproduct of particular types of nuclear reactors.

There are a few other candidates for use as space power sources that actually are waste products, but they're all significantly worse performers. There are two other alternatives. One is to make a Sterling RTG, which was in development, but funding has been cut off (it's also kind of tricky because you have to ensure that something with moving parts will operate for decades in the harsh environment of space). The other is to make an actual nuclear reactor. This means almost limitless power, but it comes at the expense of not only massive development costs and public opposition, but a large minimum size and massive radiator requirements, as well as the same reliability challenges of sterling generators.

There's no easy solutions. Except, of course, to stop bloody wasting plutonium once we have it.

Comment: Re:I'll believe it when I see it... (Score 4, Interesting) 116

by Rei (#49764673) Attached to: India Ends Russian Space Partnership and Will Land On the Moon Alone

"Love" is the nice way to put it. "Largess at the expense of all other solar system exploration" would be more accurate. Here's a graph. And it's always the same stupid justifications - how many times can we pretend to be excited about "revelations" that Mars was once in its past a wet place? Or that we're going to stumble into life any time soon in its perchlorate-rich, destroys-organics-on-contact regolith?

And it's not just huge amounts of money that they're wasting - they're also throwing away most of the remainder of our plutonium supply. At least there's money to start making it again, but it'll take time. Plutonium is precious, and it's needed for outer planet missions.

Comment: Re:Twenty five years of science destruction... (Score 2, Insightful) 116

by Rei (#49764639) Attached to: India Ends Russian Space Partnership and Will Land On the Moon Alone

I hate to be the one to tell you but academia generally pays poorly outside of the US. More so in a country like Russia that is still clawing its way back up from the economic collapse that occurred during the transition from communism to capitalism.

Perhaps if most of the country's wealth wasn't concentrated in the hands of a handful of corrupt oligarchs who live like a modern version of Roman emperors they'd be able to pay researchers a living wage.

Comment: Re:Ducted fans? (Score 1) 74

by Rei (#49763377) Attached to: The Hoverboard Flies Closer To Reality

You don't need "antigravity" (which in all likelihood is impossible). Diamagnetic hoverboards would be possible... if we could make ridiculously powerful, compact halbach arrays in the board. Also you'd need a clever mechanism to detect and deal with flying over ferromagnetic material, or otherwise it's going to smack into your board really hard.

Comment: Re: Meh... (Score 4, Insightful) 244

by Rei (#49757847) Attached to: California Votes To Ban Microbeads

The problem is, sewage treatment systems have a lot of trouble (at present, let's just simply say "can't") filtering them out. They go into the sewage, they will go into the sea.

Setting up filters for particles as small as 1 micron for all sewage going out into the ocean is obviously going to be a massive expensive. Who wants to pay for that so that people can keep sticking bits of plastic in cosmetics?

Seriously, whose bright idea was it to make bits of plastic, bite-size for plankton, looking like fish eggs, whose very design intent is to wash out into the ocean? And no, while they're not harmful to us, they absolutely will be to plankton - if not immediately (how healthy do you think you'd be if you wolfed down an entire meal-sized chunk of plastic?), then with time. Plastics act as chelators for heavy metals and a number of organic poisons, to such a degree that they might even be economical to mine. There's simply no way that this isn't going to have an impact.

And it's so stupid when one can just use soluble crystals (salts, sugars, etc) instead of plastic.

Comment: Re:Do people really take this risk seriously? (Score 5, Insightful) 230

by Rei (#49752865) Attached to: Asteroid Risk Greatly Overestimated By Almost Everyone

The article is also based on some terrible reasoning, like:

That means there will be no asteroids left in the Solar System, because they all will have struck Earth, in another few hundred million years. Think someone’s overestimated something there? Yeah, me too. Let’s take a look with the flaws in our fear-based reasoning.

Yeah, in a universe where our solar system is some sort of perfect steady state. Which, of course, it is not. Asteroids collide or - more commonly, come close to other bodies and gravitationally interact - and throw each other into different orbits. When that happens, non-Earth-crossing asteroids can become Earth-crossing ones. For example, one of the candidates for the K-Pg extinction event is a Batisma-family asteroid. This family came from an asteroid breakup 80 million years ago.

A person well versed in the field would be aware of the fact that asteroids are not in some sort of unchanging steady state. Which is why they're the ones paid to do the research on the subject.

And more to the point, we really don't have a good handle on what's out there. We have trouble making out dwarf planets in the outer solar system. We really have no bloody clue what could be on its way into the inner solar system, apart from studying how often major events happen.

And on that note, another flaw in his logic, given that until recently, the vast majority of Tunguska-style events would never even have been detected, having occurred over the oceans, remote deserts, the poles, etc. So by all means it's perfectly fair to say that the fact that an asteroid hitting earth is more likely to hit a remote uninhabited area is perfectly fair. But saying that while mentioning the rarity of inhabited areas having been hit in the past is double-counting. The historical record is evidence of how often they hit populated areas, not how often they hit Earth.

Lastly, his claim that only one person has ever been "hit by an asteroid" is ridiculous. 1500 people were injured by the Chelyabinsk one in 2013 badly enough to seek medical attention. Yes, they weren't "hit by rocks", but that's not what large asteroid impacts do; they mostly or completely vaporize by exploding in the atmosphere and/or on impact. And there's lots of reports throughout history of people getting struck by asteroids; just because they weren't documented by modern medical science doesn't mean it never happened. Seriously, what's the bloody odds that the only person to ever in historical times be hit by an asteroid would be in the 1950s in the middle of a first-world nation? Now what's the odds that someone being hit in the 1950s in the middle of a first-world nation would be well documented, publicized, and believed?

Just a lot of really bad arguments.

Comment: Re:Camer was owned by the school (Score 5, Informative) 375

The school owned the camera he used. Therefore all work from that camera belongs to the school.

No. It does not work like that. If you borrow my guitar and write a hit song, it's your song, the copyright is yours. If you borrow my camera and take a Pulitzer-winning photo, it's your photo, the copyright is yours. Copyright goes to the creator of a work, not to the owner of any tools incidental to the creation.

Comment: Re:Seems obvious now (Score 4, Interesting) 214

by Rei (#49742243) Attached to: Secret Files Reveal UK Police Feared That Trekkies Could Turn On Society

Can you imagine the dystopian dictatorship where trekkies come to power? All of the halls of power full of people walking around in spandex and fake ears and brow ridges, the fed directed to work toward the absolution of currency, the military directed to accelerate development of phasers and for all recruits to undergo "Kobayashi Maru" training.... NASA would finally get their proposed $18,5 billion dollar annual budget passed - except that the bill would have the word "annual" crossed out and the word "monthly" written in its place. National anti-bullying legislation would be passed, probably with a name like Spock's Law. And of course they'd insist on referring to the UN as the United Federation of Planets.

Comment: Re:Happens all the time in California... (Score 2) 124

by Mr. Slippery (#49722173) Attached to: Prenda's Old Copyright Trolls Are Suing People Again

and some other tiny details, such as not having a handicapped shower open to the public

What kind of business is required to have showers?

...then got stung again a year later because even though he had plenty of handicapped parking... and he only had one handicapped spot...

You have an odd definition of "plenty".

He closed up shop, and now has an antique shop in rural Texas, and making far better cash there.

If his problem in CA was with the federal ADA, that law doesn't change in TX. (The various fringe theories of some Texans notwithstanding.)

Comment: Re:All about tha Benjamins (Score 5, Insightful) 143

General skills, aka the ability to succeed in society without reverting to drug abuse, are considered when a company is hiring.

Chemcial tests can't tell whether a person is absuing drugs, only if they are using them. (It is a prohibitionist fiction that the use of certain drugs is inherently abuse.)

If the only way you can tell whether someone is using drugs is through chemical tests, ipso facto it is not affecting their performance on the job.

Comment: Re:Satellites (Score 1) 403

by Rei (#49681273) Attached to: Ask Slashdot: After We're Gone, the Last Electrical Device Still Working?

LEDs have lifespans of what, 50-100k hours? So maybe a couple decades. And some will significantly outlive their design life, as is always the case with failure curves. The solar cells should be good for decades, until the contacts corrode.

One *could* design devices to last for thousands of years. But that's not usually a design constraint ;)

Comment: Re:Indian Point == Ticking Timb Bomb (Score 1) 213

by Rei (#49657421) Attached to: Transformer Explosion Closes Nuclear Plant Unit North of NYC

There's no guarantee that ECCS are independent and can operate in the vent of station blackout. The HPCI used in Fukishima, for example, is a steam turbine-driven pump but not a generator, and it has electrical components that require operation. Which is why it didn't prevent meltdown.

The primary turbines are not designed to operate on the amount of power generated from decay heat alone.

Dead? No excuse for laying off work.

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