A classic image of Mars from the Viking lander.
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The Viking Missions

The Viking I and Viking 2 missions were designed to both orbit Mars and land and make exploratory observations on the planet's surface. At this stage in the history of the exploration of Mars, scientists had no idea what to expect nor what they might discover upon landing on the surface.

The landers confirmed the Mariner missions' bleak findings about the "lunar-esc" Martian landscape, and performed soil studies similar to those performed by Mars Pathfinder (MPF). The soils examined by the Viking missions were found to be similar, but unlike those explored by MPF!

Immediately prior to Viking 2 orbit insertion, Mars was completely enveloped in a global dust storm, rendering the surface invisible to cameras for several months. It was the first time that scientists realized the extent and potential intensity of Martain dust storms. Eventually, pictures *were* returned by the Viking orbiters and these pictures contained valuable information about Martian channels and other surface features. Among other things, measurements from the Viking orbiters helped establish the enormous size of Olympus Mons, which was first imaged by Mariner 9. Viking made more complete measurements of the shape of Mars, measurements which help scientists understand the interior of the planet and the existence of the bulge called Tharsis Ridge.

Some of the data returned from these two spacecraft are shown in the image archive below. With this data, scientists began to make the first educated guesses about what the interior, surface history, and evolution of Mars must be.

The next American spacecraft to scheduled visit Mars was the Mars Observer mission.

Last modified January 11, 2002 by Jennifer Bergman.

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