When talking about Soviet successes in space I believe the Venere missions deserve some recognition.
Just think about landing a spacecraft on a planet where the surface temperature is 450 degrees celsius (no idea what that makes in farenheit but its enought to melt lead) and the atmospheric pressure is 95 bars. Its nothing short of a hell. But the Soviets managed to relay color images from the surface.
If you ask me this i a far more impressing feat than the american mars missions.
Just look at the images
http://nssdc.gsfc.nasa.gov/imgcat/html/ ... 1_262.html
They certainly do. Soviet scientists had been very keen on landing a probe on Venus for a long time from what I understand. There was a lot of wonder about what was under those clouds (this was before there was any atmosphere penetrating radar of course). It took them more than one attempt to land a probe, but the effort they went to in this project was extraordinary. The Soviets built the worlds largest pressure cooker to simulate the Venusian environment.
Really I didnt know about the pressure cooker. Wonder how they knew about the pressure conditions before the landings? I guess you might be able to calculate it from the distance of the outer layers of the atmosphere from the surface and the planets gravity??
But offcourse the landing phase of the mission should be simplier than on Mars. On Mars you need both heatshield, parachute and landing thrusters as I understand it. On Venus you should only need to use heatshield and parachute. But still its an amazing feat.
When the they first tried to land a probe, the mission controllers saw the pressure rising very quickly until it got crushed. Knowing that this happened when the probe was still well above the surface, the scientists working on the project were able to estimate how strong a second probe would have to be in order to survive for any useful period.
I don't have a source for this online unfortunately. This is only what I remember from a documentary I saw (including the pressure cooker).
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