Catch up on stories from the past week (and beyond) at the Slashdot story archive

 



Forgot your password?
typodupeerror

Comment: Re:I'll believe it when I see it... (Score 1) 110

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) 110

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) 110

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) 243

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) 229

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:FAQ (Score 1) 134

by squiggleslash (#49750009) Attached to: Pre-Orders Start For Neo900 Open Source Phone

From what people are writing here, there are multiple definitions of "perfectly well". Someone in an above thread complains that capacitive screens require only the lightest touch, ensuring that they make mistakes when trying to use their fingernail to accurately press a specific pixel.

That, to me, says that the N900 and Neo900 do not have "touch" sensitive displays, they require pressure. I'm finding it improbable (and I'm willing to be proven wrong, but I'm increasingly sceptical as this videophilesque discussion continues) that the usual range of gestures we've come to know and, yes, love, are going to work nearly as well on that type of screen.

If I'm wrong and a light tap will always work, and a swipe will never be broken up into multiple gestures or ignored altogether, and so on, then I'd be delighted, albeit surprised the technology isn't being used anywhere else.

Comment: Re:FAQ (Score 1) 134

by squiggleslash (#49748049) Attached to: Pre-Orders Start For Neo900 Open Source Phone

I'm going to be honest, the more I read this discussion, the move I'm thrown back to old "debates" between advocates of rear projection and plasma TVs, and LCDs, all bemoaning the rise of the latter against such superior technologies as a TV that can only be viewed from one angle (and then not all at the same time), or a TV that requires all 4:3 content be shown in stretch-o-vision to avoid temporary burn-in issues. "But LCDs have a tiny bit of light visible when they're supposed to be black!" screams the videophiles, apparently oblivious to the fact that normal people rarely watch TV in rooms with no ambient light.

The resistive screen they're describing is clearly inferior to capacitive when applied to real world applications. Nobody in their right mind uses their cellphone to "paint" pictures. But everyone uses it to dial numbers, browse websites, and other activities that require a finger, or two, rather than a stylus.

But, hey, for the 0.01% of users who do actually use their cellphones more as an easel than a phone, I guess it might be useful.

Comment: Re:Taxes? (Score 1) 220

I think that is the content industry view, however rotten it might be. The idea is that if you damaged or lost a book (or some other physical item that's hard to copy), you wouldn't expect to have any choice but to buy a new copy, so why should you have a choice other than paying for replacement with music or videos?

Comment: Re:FAQ (Score 3, Informative) 134

by squiggleslash (#49744075) Attached to: Pre-Orders Start For Neo900 Open Source Phone

It has a resistive touchscreen. What's more they're saying they're going for resistive because it's "more accurate" than capacitive and capacitive would be a "step back."

I had a Nokia N800 so am familiar with the history of this platform, but it always felt like a prototype to me, and it seems like the Neo900 is still a prototype of something that would have been released ten years ago. What a shame.

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: Why content owners don't like Netflix (Score 2) 220

The problems content owners have with Netflix could be what I heard from one of them (in Europe):

- They pay very little

- They give absolutely no information about how many viewers watched the content.

For content owners, Netflix is pretty useless. For smaller movies, it may be more expensive to find and package the content to deliver than what Netflix will pay. (It is in fact time consuming to hunt down the movie files at the right framerate in the right encoding, audio matching the framerate in the wanted languages and mix versions (5.1? LtRt?, both?), subtitles in the right format and with times adjusted for variable logos etc.)

Does someone know if Netflix in the US is also so strangely secretive and also pays so little? After all, they do know exactly how many viewers watched what and when, how many interrupted without watching to the end, etc. They just don't share it per movie with the movie's owner (or rather distributor).

The world is not octal despite DEC.

Working...