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The Kármán line isn't just an arbitrary altitude, either. It's the point at which the atmosphere relatively abruptly starts transitioning from "well mixed, with a composition like at the surface" to "increasingly dominated by light and ionized species"

Of course, Kármán defined it as the rough point at which lift ceases being relevant for an aircraft moving at orbital velocities (which is also a meaningful definition).

The doors are designed differentl. Here, a picture: http://wordpress.mrreid.org/20...

All the more reason why the comparison between the two is silly.

Also this design was a continuation of the previous issues with doors opening. Car doors aren't explicitly designed not to open under water. But since the incidents with the 727s Airplane doors specifically are designed not to open in flight. The principles of air differential are not universal across planes. They are universal across cars. And there are many airplanes which open doors as part of normal operation. There's nothing special about them either.

Now a better comparison would be to say:
Car doors don't open under water for the same reason airplane doors that aren't specifically designed to remain closed are really really easy to open during flight and really difficult to close again.

The doors are designed differentl. Here, a picture: http://wordpress.mrreid.org/20...

Not this again.

I'm assuming you're just trying to be funny, but the usual formulas for gravity as a strictly attractive force apply only in an inertial frame. But it's possible, using calculus, to change the co-ordinate system to derive comparable laws of physics for a system which follows the Earth. In this frame of reference, gravity is much more interesting. So it's entirely possible, that from the point of view of an observer on the Earth, Earth's gravity is pushing this asteroid away.

And for what it's worth, as far as I remember we've never made enough 0 net charge antimatter to directly measure the force of gravity between antimatter and matter, but the assumption is that antimatter and matter attract. Otherwise funky stuff like time travel and warp drive would be possible.

According to Alcoa, the world's largest producer of aluminium, the best smelters use about 13 kilowatt hours (46.8 megajoules) of electrical energy to produce one kilogram of aluminium; the worldwide average is closer to 15 kWh/kg (54 MJ/kg). Each kilogram of aluminum in the battery produces about 8 KWH of energy, so the efficiency from plant to engine is around 60%, maybe a bit lower than charging a battery from house-delivered electricity (10% transmission loss, 80% charging efficiency, 0.9*0.8 = 0.72).

The cost of that electricity though will be the wholesale grid cost, about 3.5 cents/KWH. What do you pay for your electricity (probably three times that and up)?

Aluminum is a good way to export electricity. Iceland does this with its hydropower.

And not only is it wholesale pricing but they could even focus production on off-peak hours, at least while there aren't huge quantities in demand.

According to Alcoa, the world's largest producer of aluminium, the best smelters use about 13 kilowatt hours (46.8 megajoules) of electrical energy to produce one kilogram of aluminium; the worldwide average is closer to 15 kWh/kg (54 MJ/kg). Each kilogram of aluminum in the battery produces about 8 KWH of energy, so the efficiency from plant to engine is around 60%, maybe a bit lower than charging a battery from house-delivered electricity (10% transmission loss, 80% charging efficiency, 0.9*0.8 = 0.72).

The cost of that electricity though will be the wholesale grid cost, about 3.5 cents/KWH. What do you pay for your electricity (probably three times that and up)?

Aluminum is a good way to export electricity. Iceland does this with its hydropower.