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We've improved Slashdot's video section; now you can view our video interviews, product close-ups and site visits with all the usual Slashdot options to comment, share, etc. No more walled garden! It's a work in progress -- we hope you'll check it out (Learn more about the recent updates).

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Comment: Re:Makers or Service providers? (Score 1) 275

Yeah, keep in mind Apple recently bought "Beats by Dre" which is a music streaming service (in addition to the headphones by the same name). Apple Radio (Apple's music streaming service) has been in the iPhone for a while. There's a very good reason Apple doesn't want their users to be able to listen to free radio on their iPhone.

Comment: I wonder... (Score 1) 68

by SharpFang (#49504043) Attached to: Rocket Lab Unveils "Electric" Rocket Engine

This *might* be an avenue alternative to ion engines for flights that don't stray too far from the Sun. LEO-Moon, Lagrangian Points, inner planets. And it could be combined with ion and rocket propulsion.

You can't store all the propellant at extreme pressures simply because the tank needed to contain these pressures would be extremely heavy. There's a fine balance between weight of the tank and savings on storing pressurized fuel (both energy stored as pressure and more fuel fitting in). We're at "state of art" here and can't push that much farther.

But we can afford a *tiny* extreme-pressure tank, and we have weightless unlimited solar energy at cost of fixed-size, fixed-weight solar panels.

Run the pump with solar power, gradually pressurizing the fuel to quite extreme pressures in the dedicated, tiny, very durable tank. Release it through a narrow nozzle at extreme speeds. Speed it up even more through combustion or electric field of ion propulsion. You're converting solar energy to extra delta-v with no extra fuel usage. You have just the fixed cost of the pump+buffer tank infrastructure and they can be kept really tiny, since we don't try to get a high throughput of the fuel (and have limited energy input anyway), just to increase the propellant stored energy by transforming electricity into pressure.

Comment: Re:30 day suspension of pilot's license for prev. (Score 1) 267

by ScentCone (#49496901) Attached to: Gyrocopter Pilot Appears In Court; Judge Bans Him From D.C.
I don't believe you actually need a pilot's license to fly anything characterized as an "ultralight" aircraft, as these tape-and-balsawood gyrocopters appear to be. Doesn't mean the FAA can't fine your ass, of course, when you do dumb crap like flying a possibly deadly set of large rotors right past crowds of tourists at low altitudes in an urban area like DC.

"Pascal is Pascal is Pascal is dog meat." -- M. Devine and P. Larson, Computer Science 340

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