I made a mistake in my previous calculation: https://x.com/satofishi/status/2002924266879111386 It actually takes only ~100 years to cool Venus down to an Earth-like temperature if we block all solar radiation from reaching its surface and use the intercepted solar energy to power an economically feasible AI data center in Venus orbit. That means planetary-scale climate engineering may not be as far beyond our technological horizon as it sounds. The biggest constraints may not be the laws of physics, but the scale of humanity’s economy, along with the amount of energy, infrastructure, and industrial capacity we are able to deploy. At the current pace of growth in energy demand, we may be able to achieve planet-scale electricity generation within a few thousand years, if not sooner. If we first blocked most or all of the sunlight reaching Venus, the planet could gradually cool. As the temperature falls, the CO₂ atmosphere would eventually cross into a very different phase regime. Venus currently has an atmosphere dominated by CO₂ at a surface pressure of roughly 90 bar, so once the planet becomes sufficiently cold, a large fraction of its CO₂ could potentially condense into liquid or solid reservoirs rather than remaining in the atmosphere. At that point, the problem changes fundamentally. We would no longer be dealing with an atmosphere containing an enormous amount of gaseous CO₂. We would have a planet covered with concentrated carbon-dioxide reservoirs that could, in principle, be processed, transported, or stored much more efficiently. In other words, the first stage could be thought of as planetary cooling, while the second stage becomes planetary carbon management. Yesterday, Europe officially opened its largest industrial carbon capture and storage facility at Yara’s Sluiskil plant in the Netherlands. The project captures and liquefies up to 800,000 tonnes of CO₂ per year from ammonia production, after which the CO₂ is shipped to Norway and permanently stored 2.6 km beneath the seabed. Some may argue that this facility produces little value. It may be true on Earth. But it could serve as a real-world testbed for technologies that, in a not-too-distant future, might be adapted for terraforming Venus. The basic industrial logic is similar: capture carbon, concentrate it, transport it, and permanently remove it from the atmosphere.(Chun)