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Comment Re:the market (Score 1) 172

Having owned both the kindle with the keyboard, and the paperwhite, the keyboard had lots of issues. The keyboard wasted a ton of space despite being virtually never used, and the lighting solutions, while functional, could have looked better, and were not that battery efficient.

I think my ideal kindle would be the Paperwhite, but with physical page turn buttons.

Comment Re:free electricity! (Score 1) 201

I think your mass figures are off, that's above the maximum takeoff weight of a 747 (442mt), let alone the weight of the empty aircraft itself. Of course, somehow this 747 got into orbit, so the maximum takeoff weight is kind of meaningless.

An empty 747 weighs 178mt, and a submarine reactor weighs about 110mt. It's true that there are micro reactors that can produce about the same output at a fraction of the weight, but let's just say that we also need some radiators for cooling (since there's no active cooling in space) and call it as using up that extra weight. Some weight for the thrusters themselves, and perhaps 300 tons is a feasible weight for an unmanned spacefaring 747. Which is a totally insane phrase to say, I'll admit.

Comment Re:free electricity! (Score 5, Informative) 201

Luckily, there are existing electric propulsion technologies. They don't provide much thrust, but they're extraordinarily efficient (they require so little "fuel" as to effectively not be using any, with VASIMR producing roughly 10x-20x the fuel efficiency of chemical rockets, and the current VASIMR engine is very inefficient in terms of heat loss and such). The problem is that we've never had any large source of power in space, so while electric propulsion is great for getting your probe around the solar system with a minimum of fuel consumption, or perhaps automated cargo runs to some future colony that isn't time sensitive, they're not going to get you anywhere.

However, if you fit a nuclear reactor inside a 747, strap a bunch of if VASIMR thrusters to it, then that'd actually work. You wouldn't get much thrust, though... the 200 kW VASIMR engine produces only 5N of thrust. If you put a nuclear reactor on the thing similar to what you'd find in a submarine, you'd get 300N of thrust. Compare that to the "Draco" rockets used by a SpaceX dragon as manoeuvring thrusters... they have 400N of thrust.

Comment Re:NOT Samsung Exynos (Score 1) 47

Realize what now? The description said an Exynos for $30, and it isn't.

The Pi is too slow to do things at which it would otherwise be well suited, like for digital signage applications. A cheap little machine that can be stuck on the back of a TV doing nothing but running a fullscreen web browser would be handy.

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It's a naive, domestic operating system without any breeding, but I think you'll be amused by its presumption.

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