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Comment: Re:13,000mph? (Score 1) 201 201

Orbiting at Mach 25 is a fancy (non-scientific) way of saying fast. people go "oooh ahhh" when they hear something like that. And you are right, Mach is a local measure, and the sound speed decreases with altitude (not increasing as suggested by Artifakt). As density drops with altitude, so does the sound speed. That is why the shuttle achieves Mach 25 at the exosphere (re-entry only). Its going pretty fast and there are only a handful of molecules for every cubic meter.

Comment: Re:13,000mph? (Score 1) 201 201

Sound cannot travel in a vacuum. Sound needs molecules to transport sound waves. To determine the speed of sound, you need to know gas properties and temperature. By definition, a vacuum is space with no pressure (i.e. no molecules > molecules each contribute their own pressure, Dalton's Law), therefore no gas.

Comment: Re:13,000mph? (Score 3, Insightful) 201 201

Well, if you need to shoot down a satellite, I suppose launching a missile from something that's already going at 13000mph is easier than launching it from the ground.

Why not just put a rocket on top of the something that's travelling 13,000 mph? Keeps the costs down.

but this would be more of a concept testing for the engine, with "making it practical to use" left as work for other people.

This is probably what it is for. Someone probably already has a practical use for it, but doesn't want to reveal what that practical use would be. They just need the engine. DARPA likes to do this, where they say, "Hey design some random crazy piece of equipment that you couldn't ever fathom using. The piece of equipment must be fully functional, and we don't plan on telling you what it is for in the end. Thanks."

Comment: Re:When ideology surpasses basic mathematics (Score 1) 1040 1040

The validity of the public debt of the United States, authorized by law, including debts incurred for payment of pensions and bounties for services in suppressing insurrection or rebellion, shall not be questioned. insurrection is in the first sentence... and it isn't clear. it doesn't indicate what to do with debt owed to foreign governments. you could make the argument that obama was cleared as stated by the constitution to ignore foreign credit in favor of domestic credit... thus we would default on some loans but not others.

Comment: Re:When ideology surpasses basic mathematics (Score 1) 1040 1040

The major credit agencies should have cut when major factions of the Republican party started openly advocating a default. In violation of the 14th amendment, Section 4.

"Section 4. The validity of the public debt of the United States, authorized by law, including debts incurred for payment of pensions and bounties for services in suppressing insurrection or rebellion, shall not be questioned. But neither the United States nor any State shall assume or pay any debt or obligation incurred in aid of insurrection or rebellion against the United States, or any claim for the loss or emancipation of any slave; but all such debts, obligations and claims shall be held illegal and void."

Everyone keeps saying this applies, but Section 4 of the 14th Amendment gives a bunch of language about insurrectoin and rebellion which makes it difficult to interpret. Jury is still out on whether or not this applies to our current situation, since our debt has largely been incurred due to domestic stupidity, rather than rebellion.

Comment: Re:Main concept missing from summary (Score 1) 173 173

Where would the Sun get egg whites? If you mean glare, you'd be wrong.

Oops! Haha.

This asteroid, because of its orbit, will rise precisely four hours before the sun. So you've got over 2.5 hours of dark in which it would be visible.

This depends entirely on where you are in the world. And I restress that the asteroid is only 300 meters wide. It would still be difficult to see.

Comment: Re:Main concept missing from summary (Score 2) 173 173

If there are only 5 then why did it take so long to find this rock? Is it becaue the sun is between us an it? If so then there could be some real intersting stuff at that lagrange point.

because the rock is 300 meters wide... space is a lot larger than that. Also the sun makes it difficult to see from the ground

Comment: Re:Main concept missing from summary (Score 1) 173 173

The asteroid orbits one of the two Lagrangian points of stability of the Earth-Sun system

There are 5 Lagrange points. One on the other side of the sun, one on the other side of us, 1 ahead of earth in orbit, one behind earth in orbit, and one in between us and the sun.

UNIX enhancements aren't.

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