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Comment Re:plagiarism differs in science vs. English Lit. (Score 1) 111

"Pick up any math paper on number theory, and you're bound to find the sentence 'Let p be an odd prime number.' without citation, but that would hardly qualify as plagiarism."

I wonder how often you see specifically an odd prime number... since two is the only even prime, its really the oddest of the bunch.

Comment Re:Still skeptical about all-electric cars (Score 1) 359

Here is an interesting study on electric powertrains... it comes to some remarkable conclusions about the wheel to well efficiencies of different technologies, and the long term cost projections... Their analysis seems to point to Battery Electric Vehicles as the least likely long term solution to the transportation section, instead favoring HEVs, PHEVs, and FCVs. Very interesting read!

Comment Re:I'll wave when I drive past you ... (Score 1) 359

Hydrogen will always lose out, because it's simply an energy store and not an energy source. Anyplace we can get hydrogen from? No. We have to convert natural gas to hydrogen (might as well run vehicles on natural gas) or crack H20 into hydrogen with electricity (which is horribly inefficient). Electricity is the end game.

If electric cars were the best solution (or energy efficiency was the only concern), we would be exclusively burn oil in more efficient power plants, and using that to charge batteries in cars... rather than converting crude to gasoline to fill up.

Comment Re:Algorithms? (Score 1) 116

well I certainly am not a trajectory analyst or anything, but the guy next to me uses STK to do his analysis (the astrogator plugin). You could be right that they are using Titan to do a swingby, but I've seen some pretty crazy trajectories as a result of unstable orbits around Lagrange points. That is the basis of the space highway.

Comment Re:Algorithms? (Score 1) 116

They probably are using a tool like this to analyze possible trajectories... these tools do use numerical optimization libraries to pick paths between targets and destinations. Just guessing based on what was said in the summary, they are using the Saturn-Titan Lagrange points to alter their trajectories without using much fuel. You can do some pretty crazy maneuvers around these points.

Comment Re:Playing to the votors (Score 1) 319

NASA's budget is less than 0.5% of the federal budget, so arguing cost cutting is a red herring. Entitlement spending expansion without end as the baby boomers retire is the real structural deficit that needs to be addressed. Here is a slightly dated article that explains this a little better. And, as I understand it, they are actually expanding funding for NASA, just taking the plans for an american moon mission off the table, and redirecting that to R&D.

Comment Re:Push them further away (Score 2, Informative) 242

I think they normally push them into an orbit that will degrade so that they'll burn up on reentry. That takes less energy than putting them on a trajectory that leaves Earth's orbit.

For those lofty orbits in prime real estate (think Geosynchronous), they do push satellites out further into a graveyard orbit. It would take about 1500 m/s deltav to deorbit from way up there, and only a fraction of that to just push it a little further out of the way.

Comment Re:Yeah, orbit! (Score 1) 279

They're never going to get us into mars, because there's simply no profit in it.

Oh really? Because to me, Phobos and Deimos (Mars' moons) are little more than a few trillion tons of metal, ceramics, volatiles and a few million tons of precious metals sitting in a nice stable orbit over Mars.

Yeah but shipping charges from Mars are a bitch

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