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by GolfPopper 971 days ago
My understanding is that the biggest challenge with terraforming Venus is the atmosphere. It's roughly 93 times the mass of Earth's, and mostly CO2. What do you do with it? Cycling it into the crust would take geologic spans of time. If you just cool it, you get deep oceans or thick glaciers of CO2 covering the planet. If you've got the energy budget to actually remove it from Venus completely (or sequester it rapidly), you've probably got the energy budget to do something easier like relocate a moon or dwarf planet.

Sure, 50-60km up in the atmosphere it's fairly hospitable, but colonizing that isn't terraforming.
2 comments
holoduke 971 days ago
You would split it to o2 and carbon. The real issue is the rotation speed of venus. Almost a year to rotate arround its axis.
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cgriswald 971 days ago
What do you do with a 95% oxygen atmosphere with now only ~60 times the mass of Earth's atmopshere? You could make a small ocean out of it, but that's a huge amount of H to source.
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kbelder 970 days ago
We need to somehow get it to Mars.
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cgriswald 970 days ago
That would be useful for about 1-2% of it; but it would be better to bring it to Mars as CO2 in the first place and crazy expensive. I like the idea, though. Maybe space habitats around Venus instead.
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bloopernova 970 days ago
I've often wondered if it would be possible to spin Venus faster to shorten its day. Possibly by firing millions of large asteroids past Venus at just the right angle.

Added bonus is that you can mash all those asteroids together to give Venus an Earthlike moon.

Plus I wonder how such large scale gravitational engineering would affect the rest of the solar system.

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mrep 970 days ago
About 323 million times the energy humanity produces in a year to spin up Venus [0] so probably not anytime soon.

[0]: https://nathanielmrouth.wordpress.com/2021/04/30/what-would-...

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bloopernova 970 days ago
Thank you for a super interesting link!

It briefly mentioned the equatorial bulge that other, faster spinning, planets possess. Would it greatly damage the planet to spin it up?

I also didn't know that Venus' rotational energy is so low that we "could" actually spin it the correct way without spending much more energy.

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