171–180 of 358 posts
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I often like to quip that the [21%] corrosive gas is pretty nice today, and I think I'll go consume a big container of industrial solvent to help counteract the radiation from the uncontrolled nuclear [fusion] explosion in the sky.
Industrial solvent? Does this mean "inside air"?
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It's very unlikely the aliens would not have something very similar going on in their own biosphere. Life needs energy to operate, after all.
It might be a lot more sedate, imagine crystalline creatures from deep below the surface of an ice-ball that rely on indirect chemical gradients or geothermal. "Your planet is how close to that star!? H20 would be liquid ! How do you protect yourselves from the polar solvent leaking down into the rock?"
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If i remember right, according to one of Asimov's Foundation sequels, the Earth was unique due to its high level natural radioactivity, which allowed it to develop an ecosystem more vibrant than any other planet in the galaxy.
Was just rereading - it was the radioactivity and the large natural satellite that was unique in his universe. Tides are interesting because once you have life in the oceans, it's a kind of forcing function to adapt to land conditions
> For a time, the mantle would get hotter, since the shell around it would trap heat generated by radioactively decaying compounds inside it. As heat accumulates in the interior, the Earth in Kane’s simulations would experience an uptick in volcanism lasting for about 15 million years. That totally surprised to me. I had no idea radioactive decay played such a role for earth. It turns out I must have fallen sleep in…
The only context in which I heard it mentioned is the idea of trying to date the earth by its temperature. Assume it was a hot molten mess in the past and has been cooling down ever since. Factor in the rate at which it would radiate heat and all of the energy coming from the sun and... you conclude that the planet is very young. Because you didn't account for radioactive material within the planet, keeping it warm.
Rutherford's discovery of the atomic nucleus, and subsequent discoveries of radioactive decay (providing both mechanism and clock for Earth's heat and age) and fusion and helium (the Sun's thermodynamic equation and age) provided a refutation of Thompson's estimates, empirical basis for the current age estimates of the Earth and Sun (about 4.5 billion years), and ultimately of a lifespan for the Sun (about 10--12 billion years) as well as how long habitable conditions on Earth may persist (as little as another 800 million years for some conditions, another 2--3 billion on the outside).
https://www.teachastronomy.com/textbook/Our-Sun-The-Nearest-...>
https://en.wikipedia.org/wiki/Lord_Kelvin#Age_of_Earth> citing Burchfield, Joe D. (1990). Lord Kelvin and the Age of the Earth. University of Chicago Press. p. 43. ISBN 978-0-226-08043-7. https://en.wikipedia.org/wiki/Special:BookSources/978-0-226-...>
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> I think Newton’s third law may cause trouble No more than for a floating platform on the ocean. (Or frankly any sea or airborne firing platform.) If your launch mass is a significant fraction of station mass, and you can't counterweight, you could float it off to the side and then have the baloon detach when its engines fire. But none of this is in even the top thousand problems that come with colonising Venus.
You fly the rocket on the bottom of a plane, then fire it out. Assuming these cloud cities have landing strips, right? Managing ballast might be a challenge…
This requires engineering the rocket to withstand structural loads in two directions as well as a ~90-degree rotation under thrust. Not trivial. (It's been a major handicap for airlaunch on Earth.)
Landing on and taking off from floating platforms is like the one part of Venusian colonisation we've actually solved.
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I think that we should consider "the future". Yes, it's intangible but consider this; go back 2 centuries and ask someone if they could setup a business concern which produced millions of widgets a year. They'd think you daffy. Now beyond that, ask them to produce any manner of modern device with the precision and high consistency we have. Again, they'd think you mad, and think that such was impossible. Yet here we a…
> Yes, it's intangible but consider this; go back 2 centuries and ask someone if they could setup a business concern which produced millions of widgets a year. To go off on a tangent: two centuries ago was the height of the first industrial revolution (at least in Britain). The first time in history when this actually became realistic. The Industrial Revolution was the first time we had sustained, broad based product…
I wonder though, if not it would have been possible to build stationary steam engines with Roman tech using oversized bronze castings for cylinders. Perhaps set in bedrock to give extra strength.
Weirdly though, electric generators in watermills would have been much more attainable - except nobody had any understanding of electricity.
The funny thing is that an oxygen-rich environment is a hell-hole! Oxygen is insanely reactive and will corrode anything. Even early life on earth found oxygen toxic. It was released as a waste product by early life and they were so successful that all that oxygen accumulated resulting in the Great Oxidation Event ( https://en.wikipedia.org/wiki/Great_Oxidation_Event ). That likely resulted in many species going exti…
Yes, first everything rusted, and then the excess oxygen collected in the atmosphere. Many of our iron ore deposits we still mine today are from that rusting. (That iron used to be mostly dissolved in the oceans.)
Our present technology based on iron and steel owes itself to early life on Earth, from 1.6 to as much as 4 billion years ago. As with petroleum and coal-bed formation, a process unlikely to repeat in Earth's future. Iron ores are abundant, but still a finite resource.
https://en.wikipedia.org/wiki/Banded_iron_formation>
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Its not even about deserving it. How are going to maintain a terraforming project or build habitable orbital platforms if we can't manage keeping our natural habitat habitable?
Maybe projects like this would distract us from stupid tribalism ?
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If you make your centrifuge big enough, it's fine. But yeah, sticking rats in a centrifuge is probably a better first step than starting with humans.
> If you make your centrifuge big enough, it's fine We don't know this! We don't know how (or even if) an embryo develops under the Coriolis force, or with a gravity gradient.
The funny thing is that an oxygen-rich environment is a hell-hole! Oxygen is insanely reactive and will corrode anything. Even early life on earth found oxygen toxic. It was released as a waste product by early life and they were so successful that all that oxygen accumulated resulting in the Great Oxidation Event ( https://en.wikipedia.org/wiki/Great_Oxidation_Event ). That likely resulted in many species going exti…
Far more an Eden, then.