> Why couldn't you vacuum insulate the electronics and place some kind of radiative cooling on top of them? Radiative cooling only works if you have a hot sour

> Why couldn't you vacuum insulate the electronics and place some kind of radiative cooling on top of them? Radiative cooling only works if you have a hot source and a relatively cooler sink - on Earth, usually the atmosphere. On Venus the atmosphere is ~462 °C at the surface, so it's going to be much hotter than your electronics - so your sink will be hotter than your source, so the "raditaive cooling" will run in reverse. Also, the atmospheric pressure on Venus is very high - 92 atmospheres at the surface - the equivalent of being 1km underwater on Earth. Maintaining a vacuum chamber with this much outside pressure (not to mention temperature) would be an incredible feat of materials engineering - and would probably by extremely heavy. You would also still need sensors and communications outside your vacuum chamber, otherwise your expensive probe can't actually do anything useful.