Physically Terraforming a Hot Planet like Venus

How to physically Terraform a Hot Planet. From the writer of The Terraformers’ Toolkit.
(The Terraformers’ Toolkit: Everything you have ever wanted to know about terraforming and our future in space. The where, why, when, how and what of terraforming.) www.amazon.co.uk/dp/B09X6739P...
Venus’ surface has a temperature of nearly 500 Celsius (932 F) and a surface pressure 92 times that of Earth. Venus’ extreme temperatures are due to its thick carbon dioxide greenhouse atmosphere, which prevents infrared radiation from escaping into space.
Venus will be an enormous challenge for terraformers due to its extreme temperatures and its massive atmosphere.
Cooling
Cooling Venus’ atmosphere could be done with giant space sunshades, thousands of reflecting satellites or clouds of dust which would block much of the sunlight reaching the planet. Alternatively adding particles, balloons, chaff or thin films of highly reflective material into the upper atmosphere might also cool Venus.
Many of the plans for reducing Venus’ temperatures operate on lengthy time scales of thousands or even millions of years. However, some writers view Venus’ atmosphere as a valuable resource. If we take this approach, rather than seeing it as issue that requires a solution, humans will have an excellent source of carbon, oxygen and nitrogen for thousands of years to come. If they eventually deplete this resource, perhaps then they can consider terraforming Venus.
Extraction
Venus’ atmosphere might be a useful resource for terraforming Mars. However, Venus’ atmosphere has three times more nitrogen than Earth’s, and many times more carbon, oxygen and nitrogen than would be required to terraform Mars.
Venus could be cooled by ejecting its atmosphere into space either during massive asteroid impacts or by exploding nuclear devices. However, these gases could then pollute the inner solar system. On Earth we already have over 400 parts of carbon dioxide in our atmosphere. Increasing this substantially could sterilise our planet.
Several writers have suggested that Venus’ atmosphere could be solidified,
but it may be easier to extract gas from the top of Venus’ atmosphere than hoisting solids through the planet’s gravity well. Various writers have suggested placing ‘scoop-ships’ into elliptical orbits around Venus, dipping into the atmosphere at their closest approach. Some have suggested that tube skyhooks, space-elevators or rotating tethers could be deployed to collect supplies of carbon dioxide for use elsewhere in the Solar System.
If it were possible to accelerate the gas to a high velocity, it might be possible to direct it at specific targets such as Mars, and to keep the carbon dioxide stream thin by using a method such as ionisation or charging some of the gas.
Only once the majority of Venus’ atmosphere has been extracted would the possibility of terraforming the planet become a reality.
Day length
Each day on Venus is equivalent to 117 Earth days, which could be a problem for living organisms on a terraformed Venus as nights would be very long, cold and dark without a moon and the days exactly the opposite.
For life to exist on a slow rotation planet like Venus, more frequent light and dark periods would need to be in place. It may be possible to install a system of orbiting mirrors to reflect the Sun’s light on a 24-hour day-night basis.
Increasing Venus’ spin by transferring angular momentum from Jupiter or the Sun using an asteroid is another option. However, it might take thousands or even millions of years to change Venus’ day from 116.75 Earth days to 24 Earth hours.
Another approach would be to increase Venus’ spin using asteroid impacts. However, there may not be enough asteroids in the solar system to do this and the most useful massive metal rich asteroids may be needed for mining and our technology.
A very different approach would be to achieve a 24-hour day using a paraterraformed roof or atmosphere-retaining envelope called a ‘Worldhouse’ which would be erected over the whole of a planet’s surface. The underside of this artificial sky could be used as a screen to project the image of the Sun, moon, stars to simulate daylight and night-time on an enormous high energy output flat-screen TV. The outer surface of this roof layer could capture the energy needed to make this mega TV function.
Trying to guess which technologies our descendants will have in a thousand years is like people in the year 1000 trying to forecast computers, air travel and nuclear power. This means that the things our descendants will be able to achieve will be well beyond our expectations. Today we can only base our best guesses on the laws of physics and our own imaginations.

[@YellowTroutLily]

I purchased your book on this topic and it arrived today. I am enjoying and pondering this future history

[@charlesjoynson7758]

Thank you.

[@randydicotti3975]

Since the slow but steady expansion of our Star will work against such massive efforts, perhaps it would be wiser to work with the outer moons and planets which would have the benefit of becoming more habitable as our Star expands and also give us more time.
that said, if it absolutely had to be done you give some very thoughtful paths towards terraforming a hot planet. Perhaps technological breakthroughs and or the advancement of artificial intelligence and robotics will expedite such endeavors in the future.

[@charlesjoynson7758]

Thanks for your reply Randy. Terraforming Venus is likely to take place in the coming 10,000 years. That gives us plenty of time to use the planet's atmospheric resources. The expansion of our star will happen, but in hundreds of millions of years. By then our descendants will probably all over our galaxy.