"[In 1958] some astronomers thought that Venus might have a rotation period near the 24-hour mark, as Earth and Mars do. In that case, the microwave emission might be quite copious even from the dark side, since that would have been exposed to the Sun a few hours before. In that case, microwave emission might indicate a roughly Earthlike temperature, since the fact that Venus is closer to the Sun might be balanced by the fact that its cloud layer reflects most of the sunlight it receives. Well, [[w:Cornell Mayer|[Cornell] Mayer]] did detect the microwave radiation from Venus and he did not get either expected alternative. He did not get a very low temperature of a dark side that never sees the Sun, nor did he get an Earthlike temperature, nor, for that matter, anything between. Instead, he got a flood of microwave radiation that indicated a temperature of at least 300° C, some two hundred degrees above the boiling point of water. It was a thunderbolt. No one had expected such a hot Venus."