by whom?
UNANSWERABLE
the atmospheric pressure on the surface of venus is 93 bar (9.3 MPa) when was this planet discovered? 1761
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Atmosphere of Venus [SEP] History
Mikhail Lomonosov was the first person to hypothesize the existence of an atmosphere on Venus, based on his observation of the transit of Venus of 1761 in a small observatory near his house in Saint Petersburg, Russia.