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On this day in 1990 – August 10th – NASA's Magellan spacecraft entered orbit around Venus to begin radar mapping of the surface.
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Did they get a lot of good photos?
Well, Angie, yes and no. They didn't get any actual photographs of the surface, because visible light can't penetrate Venus's thick clouds. But the planet was mapped using radar which has a longer wavelength than visible light and is able to penetrate the clouds. What we can see in the radar images is the contours of surface features.

Here is a surface map of Venus made from Magellan imaging plus some data from the Areceibo Observatory. The color coding shows elevation using data from Magellan, the Soviet Venera spacecraft and NASA's Pioneer Venus mission.

[NASA/JPL/USGS]