Soils form through a complex interaction of the molecules of soil with particles and molecules of the atmosphere. Measurements of the soil contribute to an understanding of a planet's climate, weather, surface processes, and atmospheric composition because of the way in which soils form.
The first analysis of Mars' soil from Viking landers found no evidence of life, instead showing that organic molecules are even more scarce than on the Earth's moon. The Viking missions did confirm the presence of water in the soils and atmosphere, in both solid and vapor form. The soils found near the rocks explored by Mars Pathfinder's Rover were similar to those found by Viking I (check the large topographic map of Mars for the distances between these two landing sites), even though the rocks were not. At the Viking landing site the rocks were commonly coated with a bright red dust, while at Ares Vallis, these rocks were rare. Instead the rocks seemed to be mostly dark gray in color. This suggests that soils of Mars may be uniform around the globe, perhaps carried all over Mars by global dust storms.
Scientists did not find evidence of hematite or maghemite - iron bearing minerals, near the Pathfinder landing site. Mars is expected to have more than the ususal amount of iron in the top soil (hematite and maghemite are magnetic materials), since the core is small, and the magnetic field, generated in the interior, is weak. Scientists are busy trying to understand this puzzling result.
One of the objectives of the Mars Pathfinder mission was the examination of the composition of the soil and how it was laid down. As the Rover traversed the surface exploring the rocks of Mars, it also...more
An important new result from the Mars Global Surveyor (MGS) mission is the definite confirmation of the presence of a magnetosphere around Mars. Previous missions did not make really good measurements...more
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...more
The Phoenix Mars Lander was a robot spacecraft that was sent to Mars. Phoenix landed near the North Pole on Mars. This page tells about the mission of Phoenix. It also describes the instruments on the...more
The Mars Odyssey was launched April 7, 2001, from Florida. After a six-month, 285 million-mile journey, the Odyssey arrived at Mars on October 24, 2001. The Odyssey is in its aerobraking phase right now....more
The Mars Global Surveyor reached Mars in September of 1997. But it didn't make it into its final mapping orbit until February 1999. What took so long? Surveyor needed to reach a near-circular, low-altitude...more
