On June 12, 1967, Venera 4 was launched into space on a mission to Venus, thus becoming the first spacecraft to transmit data from another planet's atmosphere.
This was a Russian probe designed to study the atmosphere of Venus down to the surface.
At first, scientists believed that the probe had transmitted until contact with the surface of Venus. But transmissions had ended at an altitude of 16 miles (or 27 kilometers), when the extreme temperatures and high atmospheric pressure crushed the probe.
But from the data collected by Venera 4, we learned that Venus' surface temperatures were 500 degrees Celsius and the pressure was 75 times more than Earth's. It also found that Venus' atmosphere was composed of 90 to 95 percent carbon dioxide with no nitrogen.
The 10 Weirdest Facts About Venus
Venera 13 and the Mission to Reach Venus
Venera 7, 1st to Send Data from Venus Surface, Launched 45 Years Ago
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Email Hanneke Weitering at hweitering@space.com or follow her @hannekescience. Follow us @Spacedotcom and on Facebook.
