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What made Earth a giant snowball 700M years ago? Scientists have an answer

sydney.edu.au

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Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#71

Post by DiogenesKynikos »

nullhole wrote: post #19
itronitron wrote: post #3

Seems like a low risk approach for taking over a planet would be to just park a large shade between the planet and it's star then let it enter a deep freeze. Then you could just remove the shade and let the planet warm back up before settling down.

That'd make for a good story setup: aliens park a shadeship (c) at L1 and wait. They block out most but not all of the sun. After some time (months? years?), conditions on Earth become unbearable, so earthlings have to mount an attack. Kind of like the movie Sunshine, but with more believable physics. Edit: as a bonus, it could take place in ~50-100 years, when global warming has gotten worse. The aliens could disgui…

An embargo on light.

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#73

Post by tempestn »

Archelaos wrote: post #41
itronitron wrote: post #3

Seems like a low risk approach for taking over a planet would be to just park a large shade between the planet and it's star then let it enter a deep freeze. Then you could just remove the shade and let the planet warm back up before settling down.

"Just parking" between would not be possible without putting really a lot of energy into maintining the position of the shade. Due to orbital speed differences depending on the distance to the sun[1] and the pressure of the light[2] and solar wind[3] on the shade and Earth's gravitational interference. And the shade must be very much larger in diameter than the planet in order to cover it. How large depends on the di…

You would want to place it slightly on the sun side of the L1 point, where gravitational and solar wind forces cancel out.

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#74

Post by whartung »

nullhole wrote: post #19
itronitron wrote: post #3

Seems like a low risk approach for taking over a planet would be to just park a large shade between the planet and it's star then let it enter a deep freeze. Then you could just remove the shade and let the planet warm back up before settling down.

That'd make for a good story setup: aliens park a shadeship (c) at L1 and wait. They block out most but not all of the sun. After some time (months? years?), conditions on Earth become unbearable, so earthlings have to mount an attack. Kind of like the movie Sunshine, but with more believable physics. Edit: as a bonus, it could take place in ~50-100 years, when global warming has gotten worse. The aliens could disgui…

Who would like to do the math on how big the shade would need to be and how long it would take to reach a tipping point?

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#75

Post by sidewndr46 »

ljf wrote: post #29
nullhole wrote: post #19

Earlier quoted context omitted.

That'd make for a good story setup: aliens park a shadeship (c) at L1 and wait. They block out most but not all of the sun. After some time (months? years?), conditions on Earth become unbearable, so earthlings have to mount an attack. Kind of like the movie Sunshine, but with more believable physics. Edit: as a bonus, it could take place in ~50-100 years, when global warming has gotten worse. The aliens could disgui…

Love this idea for a story. As an alternative - it could be the oil producing countries, not aliens - seeking shade earth to disrupt solar and wind energy, and return to oil dominance.

This sounds more like something out of a Mad Max type universe rather than sci-fi. A world living off fossil fuels because daylight has been reduced to 10% of the normal duration or something like that.

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#76

Post by tommywg7 »

nullhole wrote: post #19
itronitron wrote: post #3

Seems like a low risk approach for taking over a planet would be to just park a large shade between the planet and it's star then let it enter a deep freeze. Then you could just remove the shade and let the planet warm back up before settling down.

That'd make for a good story setup: aliens park a shadeship (c) at L1 and wait. They block out most but not all of the sun. After some time (months? years?), conditions on Earth become unbearable, so earthlings have to mount an attack. Kind of like the movie Sunshine, but with more believable physics. Edit: as a bonus, it could take place in ~50-100 years, when global warming has gotten worse. The aliens could disgui…

Alternative, more physically feasible attack—-aliens take over the moon and begin pushing it closer, messing up tides/weather etc. Humans are forced to fight to take back the moon

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#77

Post by cwillu »

tommywg7 wrote: post #76
nullhole wrote: post #19

Earlier quoted context omitted.

That'd make for a good story setup: aliens park a shadeship (c) at L1 and wait. They block out most but not all of the sun. After some time (months? years?), conditions on Earth become unbearable, so earthlings have to mount an attack. Kind of like the movie Sunshine, but with more believable physics. Edit: as a bonus, it could take place in ~50-100 years, when global warming has gotten worse. The aliens could disgui…

Alternative, more physically feasible attack—-aliens take over the moon and begin pushing it closer, messing up tides/weather etc. Humans are forced to fight to take back the moon

Shifting the orbit of the moon is more believable? Than placing a mega structure at L1 (which despite being mega, would be orders of magnitude less mass than the moon)?

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#78

Post by Tangurena2 »

tommywg7 wrote: post #76
nullhole wrote: post #19

Earlier quoted context omitted.

That'd make for a good story setup: aliens park a shadeship (c) at L1 and wait. They block out most but not all of the sun. After some time (months? years?), conditions on Earth become unbearable, so earthlings have to mount an attack. Kind of like the movie Sunshine, but with more believable physics. Edit: as a bonus, it could take place in ~50-100 years, when global warming has gotten worse. The aliens could disgui…

Alternative, more physically feasible attack—-aliens take over the moon and begin pushing it closer, messing up tides/weather etc. Humans are forced to fight to take back the moon

So. That sounds like an idea for a sequel to Iron Sky. But with Space Aryans™! and not space aliens.

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#79

Post by Tangurena2 »

sidewndr46 wrote: post #75
ljf wrote: post #29

Earlier quoted context omitted.

Love this idea for a story. As an alternative - it could be the oil producing countries, not aliens - seeking shade earth to disrupt solar and wind energy, and return to oil dominance.

This sounds more like something out of a Mad Max type universe rather than sci-fi. A world living off fossil fuels because daylight has been reduced to 10% of the normal duration or something like that.

Or the "water company" from Tank Girl - blocking the sun to drive up revenues for the oil/coal companies.

Re: What made Earth a giant snowball 700M years ago? Scientists have an answer

#80

Post by Timon3 »

exoverito wrote: post #57
DelaneyM wrote: post #50

Earlier quoted context omitted.

I mean, a trillion dollars to solve global warming sounds like a pretty good deal to me?

It's not solving if they can turn it back on, it's a subscription. The elite want renters, 'you will own nothing and be happy'. It should give people pause that with all the push for more renewables in California and Germany, they now have among the most expensive electricity on Earth.

You're conveniently leaving out that, at least for Germany, this was already the case before.
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