We wouldn't be able to build enough drilling plants on top of it to make any reasonable dent in the energy contained there. I agree that we would get plenty of usable energy from it, but we would not be able to stop the expansion.

How do you think they get the robot to Mars?

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.

good luck with that in the upper reaches of the atmosphere...

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.

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

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."

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.

"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.

if you are looking at "trends", then you aren't actually predicting anything. Predicting requires physical models, not data.

Weather predictions have been historically inaccurate. Why would anyone think that global warming or this new paper are any more accurate? We won't know that global warming is coming until it hits us, much like we won't know an ice age is coming until it hits us.

Oops! Haha.

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.

yes but the sun would also give a glair on any ground-based telescopes...

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

I am surprised they haven't found this before. They are planning on installing satellites at L4 and L5, you would think they would figure out if there was anything there waiting on us.

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.