It could actually be done, by sending a million or so Oort cloud comets to fly close by Venus, a few thousand kms above the surface, At least - that is enough to move Earth out to Mars orbit, rather similar task.
There's also a clever way to do it with a large solar sail balanced between Venus and the sun. Both methods described here, but as methods for moving the Earth.
Moving the Earth: a planetary survival guide
Another method for the Earth involves repeated flybys of the Earth and of Jupiter.
Assuming loads of time and patience and high technology, it could be done.
As for making Venus like Earth - it is actually surprisingly similar except for the loss of water.
If you could somehow deliver entire oceans worth of water to Venus - then the CO2 would react over long periods of time, to form limestone + organics, under action of life. And the extra water would lubricate the crust and may switch it to a "continental drift" type pattern like the Earth. Instead of its current global upheaval every few hundred million years approach.
Combine all that with moving it further away from the sun, and it might just work.
After all Venus they think was a near twin of Earth originally. So - add lots of water and maybe you can turn back the clock - make it like early Earth - and then gradually move it forward in time again to somewhat resemble Earth.
Again needs lots of patience, and thousands and millions of years of time to do it. But for a long lived patient and high technology civilization, it could be done I think.
You would have to be careful about the stability of the solar system. Especially - what happens to the very light Mercury - if its orbit goes unstable and it starts careering through the solar system it might be a problem.
There's also a clever way to do it with a large solar sail balanced between Venus and the sun. Both methods described here, but as methods for moving the Earth.
Moving the Earth: a planetary survival guide
Another method for the Earth involves repeated flybys of the Earth and of Jupiter.
Assuming loads of time and patience and high technology, it could be done.
As for making Venus like Earth - it is actually surprisingly similar except for the loss of water.
If you could somehow deliver entire oceans worth of water to Venus - then the CO2 would react over long periods of time, to form limestone + organics, under action of life. And the extra water would lubricate the crust and may switch it to a "continental drift" type pattern like the Earth. Instead of its current global upheaval every few hundred million years approach.
Combine all that with moving it further away from the sun, and it might just work.
After all Venus they think was a near twin of Earth originally. So - add lots of water and maybe you can turn back the clock - make it like early Earth - and then gradually move it forward in time again to somewhat resemble Earth.
Again needs lots of patience, and thousands and millions of years of time to do it. But for a long lived patient and high technology civilization, it could be done I think.
You would have to be careful about the stability of the solar system. Especially - what happens to the very light Mercury - if its orbit goes unstable and it starts careering through the solar system it might be a problem.
About the Author
Robert Walker
Writer of articles on Mars and Space issues - Software Developer of Tune Smithy, Bounce Metronome etc.Studied at Wolfson College, Oxford
Lives in Isle of Mull
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