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Comment Re:If the singularity doesn't happen... (Score 1) 111

Stop feeding the troll ;) If a person can't handle an argument without name calling, they're not worth your time.

For what anyone not trolling :) There is nothing magical about existing on Earth that allows a nuclear reactor to run. Earth does provide a few conveniences, mind you - your mass budgets are unlimited, and cooling is easier. But nothing about either bulk nor mass prevents nuclear reactors from operating in space, by any stretch, and the two main things limiting their use have been a lack of need and NIMBY (the former being little applicable in the former USSR, they used them quite a bit, although they still lacked a need for high powers and so generally kept them fairly small; in the US, NIMBY limited the US to just one launch, although the US developed a number of other systems, some to flight-ready status, on the ground).

The typical mass balance for a in-solar system fission fragment rocket (measured simply by MWt, not MWe, since thrust is direct) is about 20% payload, 20% structural, 35% reactor, and most of the rest toward various aspects of cooling. The nuclear fuel makes up only about 2% of the total mass (figures from the Callisto baseline). For an interstellar mission, however, the fuel would make up the a large minority or the majority of the mass, trading significantly reduced acceleration for significantly longer acceleration times. On an in-solar-system version, power density is about 6kWt per kilogram of reactor mass (that 35% figure above). This is actually quite low by large-space-reactor standards; many modern multi-megawatt reactor research projects for NEP and defense purposes (example) often deal with density figures of 50-100 kWe per kilogram, including cooling. But a fission fragment reactor has a sparse core and has to rely extensively on moderation / reflection to keep up a sufficient neutron flux; higher core density is prohibited because then the fragments would thermalize.

One thing that's neat about a fission fragment reactor is that, like systems like VASIMR, it can operate in various output modes, trading ISP for thrust as needed. In pure fission fragment mode it's ISP is is ridiculously high, nearly 1m sec; your thrust is purely the relativistic fission fragments from each reaction, carrying the majority of the reaction's energy away. However, you can inject gas into the stream as reaction mass, limited only by the density to which your magnetic nozzle can keep the stream confined. So where higher thrust maneuvers are needed, you can use the same engine (up to the aforementioned extent, of course; you're not going to take off from a planet with a FFRE!)

Comment Re:The Change (Score 1) 110

It depends where you draw the line for "humanity". The first shaped stone tools are concentrated in Africa.

Later stone-tool-making hominids did spread out, and it is possible an isolated group became "humanized" at a faster pace and then spread back into Africa and elsewhere.

(I mention stone tools because chimps are known to sharpen wooden sticks with their teeth.)

Comment Re:Taxonomy and location (Score 1) 111

So it's up to the planetary scientists to do something about it if they think it makes little sense

Do what? They make up less than 20% of the membership of the IAU. It's a bunch of astronomers. What do you want them to do, file a lawsuit?

They're doing the main thing that they can, which is complain about the "definition" foisted upon them, as Stern was doing above. Something you apparently find fault with.

All I hear is a bunch of bitching about it but no serious counter proposals.

That's your fault if you don't pay attention to the debate, because there have been tons of alternate proposals.

If the IAU decision wasn't scientifically useful then it will be ignored anyway.

And hence a giant stink that lowered the discourse for nothing.

How do you see this as even remotely similar? If you take a shrew from Ohio and you place it in Nepal, does it cease being a shrew and become a dwarf shrew that no longer counts as a shrew?

Actually biologists do stuff like that all the time.

No, they don't.

There are species that are considered different based almost entirely based on location

No, there aren't.

but it does happen and it's not irrational.

No, it doesn't, and yes, it is.

Seriously, you're going to cast doubt on the guy who came up with the Stern-Levison parameter that's used to make that distinction?

When he says something igorant, yes I am.

Right. Got it. The guy who co-invented the Stern-Levison parameter doesn't know how to calculate a Stern-Levison parameter. But you do. Thank you! I take it your name is Harold Levison?

Pluto is absolutely not "much like" "big rocks", and the fact that you'd make this claim is a profound expression of ignorance on the topic.

You are seriously arguing that Pluto is nothing like other "dwarf planets" or other large rocky/icy objects in our solar system?

Pluto is more like Mars than it is Ceres, at the very least. As for other dwarf planets... we have no idea, we've never even been there. Going by things that would be counted as dwarf planets if they were free orbiting, there's a massive range of properties. What's the universal property (apart from size / hydrostatic equilibrium / general terrestrial nature) between Pluto, Luna, Ceres, Ganymede, Callisto, Europa, Io, Titan and Triton? Answer: not a damn thing. They're all radically different environments. Some are more similar to each other than others, but they're anything but a logical "group" distinct from the terrestrial planets.

Versus "big rocks", however, the comparison is even more ridiculous. There is literally nothing beyond "they're both made of solid matter" in common between Pluto and a typical large asteroid. Including, for starters, Pluto isn't made of rock. It has some unknown percentage of rock in its interior, but it's overall made of ices, with a thin gas atmosphere (not all that different, structurally, from the ice giants Neptune and Uranus, although the latter two are obviously on a much larger scale and reach much higher pressures in the gaseous state before transitioning to the ice states).

Comment Re:If the singularity doesn't happen... (Score 1) 111

I'm sorry, I must be a nutter. I was under the mistaken view that we live in a world where there are many dozens of different designs for fission reactors that have been developed, with new designs being developed and prototyped every year, and full scale reactors being produced on scales orders of magnitude larger than is required for spacecraft propulsion. Little did I know! Thank you for correcting me for my sinful error.

Comment Re:Publishers unwilling to grant a license (Score 1) 80

Because it would be much more expensive to use hardware that is capable of emulating a NES through software than it would be to use a NES on a chip or FPGA.

Nintendo can probably buy a common ARM SoC including the HDMI driver for cheaper than it'd take to engineer and manufacture an accurate NOAC with all the relevant mappers included. Existing NOACs tend to have problems, such as inverted duty cycles, audio distortion, and no digital output.

They have a choice. Make $1/$2 per copy or make $0 per copy. It's not hard to see which of those makes more sense.

Consider the NES games Bart vs. the World and Lethal Weapon. If the upstream licensor of the movie or TV series on which a game was based wants $3 per copy, then for every $1/$2 copy the game publisher sells, it has to pay $3 to the movie or TV studio, resulting in a loss of $2/$1 per copy. In this case, earning $0 by not licensing at all would at least stop loss.

Notice how the controller bundled with the NES classic isn't the controller bundled with the Wii?

The controller bundled with the Wii was the Wii Remote and Nunchuk. All NES Virtual Console games work with the Wii Remote held sideways.

Comment Re:What the hell is the big deal with "planet"? (Score 1) 111

The most ridiculous thing about the "cleared its orbit" standard is... MOST planets didn't clear their orbit. Jupiter, and to a lesser extent Saturn, did. Particularly in the case of Mars. Mars does not dominate it's neighborhood, a fact clearly reflected by how low of a percentage of asteroids are in a Mars resonance vs. Jupiter. Mars has a significantly lower Stern-Levison parameter than Neptune, and yet Neptune has freaking Pluto in its neighborhood. And even if one wants to argue that Pluto is too small versus Neptune to count as "not cleared", it certainly isn't too small compared to Mars to count. The reason Mars does not have things even bigger than Pluto in its neighborhood comes down to one word: Jupiter.

And I know some people will say, "but the Stern-Levison parameter says Mars would have". It says no such thing. The Stern-Levison parameter is about a body's ability to relatively clear its orbit of asteroids, not protoplanets. It's based around the size and orbital distribution of our current asteroid belt.

But of course, this was not a scientific reality seeking a definition. They had a definition they wanted (that Pluto wouldn't be a planet) and were trying to come up with some sort of scientific reasoning, any reasoning, as to why. This is quite clear from their statements on the topic, they already had the result they wanted and were playing around with different reasonings to get it. And this mangled, self-contradictory definition is what they came up with and passed at the last minute (when most people had left thinking that there either wasn't going to be a new definition or that it would be based around hydrostatic equilibrium, based on what had been discussed previously, and were fine with either outcome). And so now we have a situation where a "dwarf X" isn't an "X" from a body that otherwise declares dwarf things to be smaller versions of the same thing, where exoplanets aren't planets, based on a lie that all planets have "cleared their own neighborhoods", without any sort of clear definition as to what a "neighborhood" or "clear" is.

Heck, if I wanted to be pedantic I could point out that not even Jupiter would meet their definition because - again, to be pedantic - it does not orbit the sun. The point that Jupiter orbits (the Sun-Jupiter barycentre) is almost always outside the sun.

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