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Comment Re:Mission Creep (Score 1) 32

Most of the energy is spent getting to orbital speed, not getting the necessary altitude.

Changing the inclination of the orbit is expensive in energy.

Orbital speed and altitude are functional, if you want to increase altitude, you just accelerate to a higher speed, changing speed takes work in orbit. On the moon you can orbit just inches above the highest obstacle in your path.

The velocity of an object is the rate of change of its position with respect to a frame of reference, and is a function of time. Velocity

In orbit you frame of reference is the center of gravity of the Earth
to change inclination, Newton's First law applies

When viewed in an inertial reference frame, an object either remains at rest or continues to move at a constant velocity, unless acted upon by an external force Newton's laws of motion

you just give the satellite a quick burn at a vector giving it a lateral motion and it begins to move and doesn't stop until you do a breaking burn, I.E Newton's first Law, how much energy it takes depends on how quick you want to get there; the geographical location of abstract surface details like the equator or the rotational pole are meaningless to the satellite.

Think about it, what is easier walking 130 feet across a parking lot or walking up 13 floors worth of stairs? If you roll a bowling ball across the parking lot it keeps going until friction consumes it's kinetic energy, try rolling it up a handicap-ramp and see how quick gravity eats up the kinetic energy!

Comment Re:Mission Creep (Score 1) 32

I don't think so, most of your energy budget is spent just getting to any orbit. Changing inclination is trivial because it's a zero-work manoeuvre as momentum is conserved, one burn starts you changing inclination and it continues until you do a breaking burn. Changing altitude is expensive because you have to accelerate out of the gravity well.

    ISS is orbiting at 409 km - 416 km with an orbital inclination of 51.65 degrees and orbital period of 92.69 minutes, a Molniya orbit is inclined 63.4 degrees and orbital period of 720 minutes, tungra orbits are inclined 63.4 degrees and orbital period of 1,436 minutes and Clarke orbits have 0 inclination and an orbital period of 1,436 minutes

Comment Re:News reports: Volkswagen used special hardware. (Score 2) 416

When I read the article linked, it was clear that VW used hardware as part of the "cheat device", just that hardware would have to be changed to meet emissions testing on the first and second generation TDLs. Perhaps I'm being generous but if VW emission engineers didn't know about the "cheat device" then it's likely that the hardware was never tested without the cheat.
My point was the VW demonstrated the ability to change emissions profile to increase performance and fuel mileage (basically trading less CO2 for more NOx) based external conditions, then they can do it on purpose base on external conditions like location via GPS, whether an ozone action day has been called.

Comment Re:Maybe (Score 3, Informative) 416

All manufacturers designed their engine/transmission management systems to pass the test, what happened outside the test conditions were in the "your actual mileage may vary" zone; It's just like "common core" where they teach the kids to specifically pass the test. If you want cars to perform under realistic driving conditions the same as they do under emissions test, you have to make the test conditions as close to realistic as possible. The big three used to test their suspensions by driving down a particular bumpy section of Woodward avenue in Detroit, when they announced that that section of road was going to be repaired and repaved, the manufacturer surveyed the road and duplicated it at their test tracks to maintain continuity, and keep the test as close to realistic as possible.

Volkswagon's mistake was they actually change the operating parameters based whether the vehicle was being tested for emissions or for mileage or under normal conditions, the next step is for the bureaucrats to realise that they can have vehicle emit differing levels of emissions based on location and weather; your car may suck donkey balls in San Francisco, but run like a champ in Montana.

Comment Re:One sentence stands out as most interesting (Score 1) 141

Triggering crystallisation of a planet's core is left as an exercise for the reader, and would be incredibly difficult, but it's a lot more plausible than trying to supply enough heat to start convection by any other means.

interesting questions might be

  1. How much nuclear waste would have to be dumped down a borehole on Mars to remelt the planetary core; ( I know it's an insane amount, but how insane)?
  2. How long would it take to melt?
  3. How deep would the borehole have to be, at some point the waste would melt and go into "China Syndrome mode" and melt it's way down?
  4. Should we crash some icy asteroids into the planet to get some potential oxygen from water before or after we restart the core?
  5. How many rocky/metallic asteroids should we crash into Mars to get the gravity up?
  6. Would it just be easier to build a ring-world?
  7. Could we harvest gasses for atmosphere from Jupiter?

Comment Re:This is basic planetary physics.. (Score 4, Interesting) 141

The way I understand it the lost of the magnetosphere allows the solar wind to push the ozone back to the nightside and some off into space, this thins ozone lets the UV disassociate more water vapor (that's lighter than air) into hydrogen and oxygen, the hydrogen is lost to space because it's so light and the oxygen that doesn't get blown off into space oxidises any methane or carbon monoxide in the atmosphere on the way back down to the surface. This causes the atmospheric pressure to decrease, which cause the water to boil at a lower temperature, putting more water vapor into the air to be dissociated and lost, in an accelerating death spiral.

Comment Re:sigh (Score 1) 132

"decimated nearly half the population in the Mediterranean"

So unless it really killed 1/10 of half the population of the Med basin, you don't know what 'decimated' means?

It's ok, it's not like this stuff is edited.

So it didn't decimate but semimated the Europeans, not to be confused with inseminated.

Comment Re:Decentralized power (Score 1) 419

That's good for a few hundred watts, but something for a more normal household that needs KW's and a tower higher than the tree tops for clean wind. These towers look more like a commercial radio tower and the average bloke isn't going to climb one to grease the bearings or change the diodes in the alternator, the pads on the speed-break or the brushes in the the commutator. The guy that's seriously living off the grid is likely to be able to handle it, the guy that's doing it to be "green" or to "stick it to the man" isn't likely to be able to handle it.

Comment Re:Time to drop the prices? (Score 1) 419

So my electricity bill's going to go down now? No, I didn't think so either.

No, because part of the reason wind/solar is more competitive is because the more wind/solar you have, the more expensive fossil fuel power becomes. It is explained in TFA.

No TFA said

t’s a self-reinforcing cycle. As more renewables are installed, coal and natural gas plants are used less. As coal and gas are used less, the cost of using them to generate electricity goes up. As the cost of coal and gas power rises, more renewables will be installed.

What the article did say is the marginal costs of Renewables are zero, where legacy systems have their marginal cost tied to fuel expenses, the article didn't address fixed costs i.e. how much it costs to make no electricity and that is considerable cost in both cases. A lot of expenses have been subsidised for renewables,
1. they didn't have to pay for offline backup power sources,
2. they didn't have to pay for transmission infrastructure
3. people pretended they had no negative environmental impacts
4. construction costs were subsidized
5. there were no decommissioning funds
When all of that gets added back into the cost of renewables, plus the cost of the green subsidies, people are going to talk fondly of the "Good 'Ol Days" when you didn't have to plan your day around whether the sun was shining or the wind was blowing.

Comment Re:Show us the data (Score 1) 419

The hard evidence, the data is in the stocks of the big four (EnBW, E.ON, RWE, Vattenfall) being in free fall for years now, while them desperately searching buyers for their outdated, in deficit fossil plants. Recently they even tried moving them into bad-bank-style shell corps.

That's actually the trend everywhere, companies are spinning off their "Carbon Intense" assets into separate operating units or even whole new companies. The old "Carbon Intense" assets can't compete with the renewables when the conditions are favorable, and renewables can't compete when conditions are unfavorable. This way the utilities get to externalize the cost of base load and peaking to their legacy systems which drives up their expenses and the regulators have to allow rate increases to return them to their allowed 15% profitability, the legacy systems can not be allowed to fail or we lose backup. The renewables will never have their rates cut no matter how much they are making because it "saves the planet" and all of that!

Science is what happens when preconception meets verification.