Astronomy 105G Lecture Notes, 05 Mar. 2004

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Collection of Lunar Rocks - Apollo 15


Image from http://www.nasm.si.edu/collections/imagery/apollo/FIGURES/LandingSitesMaps.jpg





Geology of Venus

Relatively little was known about the surface geology of Venus before the space age, since the planet is surrounded by a thick layer of clouds:







Spacecraft exploration of Venus began in 1962, followed by a number of Soviet missions (including landers) in the 1970's and 1980's. The first surface photographs of Venus were returned in 1975; this is what they saw:







Here is a web page with more images from the surface of Venus.





The first radar maps of the Venusian surface were made by Pioneer Venus in the late 1970's. These maps revealed continent-sized elevated regions among lower elevation volcanic plains:







However, most of what we know about the surface geology of Venus results from the Magellan mission to Venus in 1991-1993, which used imaging radar to study the surface of Venus.







Magellan revealed a world below the clouds that resembles Earth if we had no erosion here. There are impact craters, extinct volcanoes, and evidence for early plate tectonics. There is no evidence for plate tectonics still occurring today on Venus.



Some surface features on Venus include:

Here are some cool computer-generated movies of flying over the surface of Venus.