An aerobot with ISRU capabilities could explore Venus' atmosphere for years

In Dante's "Divine Comedy," Hell is described as an "inferno" with nine concentric circles, the entrance of which has a sign that reads "Abandon all hope, ye who enter here." For the planets of the solar system, Venus is about as close to this description as one can get. On the surface, temperatures are hot enough to melt lead (464°C; 872°F), while the atmosphere is dense enough to crush a human skull (more than 90 times Earth's atmospheric density). However, above the cloud deck, roughly 47–70 km (29–43 mi) above the surface, temperatures are stable, and the atmospheric pressure is roughly equivalent to Earth's.