NASA’s Mars Pathfinder mission is designed to demonstrate the technology required to deliver a lander and a robotic vehicle to the planet’s surface. It launched on December 4, 1996, and landed on Mars Ares Vallis seven months later on July 4, 1997. The Pathfinder mission not only fulfilled its goal of being a technical demonstration, but also returned a lot of data.
The Mars Pathfinder mission entered the Martian atmosphere using an innovative method in which the spacecraft used a parachute to slow its descent and a massive system of airbags to cushion the impact on the surface. The mission carried the Carl Sagan Memorial Station (the probe) and the Sojourner rover, both of which lived longer than their design lives.
Both carry scientific instruments for analyzing the Martian atmosphere, climate, geology, and rock and soil composition. From the time of landing until the final dispatch date, Mars Pathfinder has returned more than 16,500 images from the probe and 550 images from the probe. They also returned chemical analyzes of the rocks and soils, along with extensive data on wind and other weather factors. Scientists who study Mars still use these images and data.
The results from this data are what helped scientists conclude that Mars was warm and humid, with liquid water lying beneath its thin atmosphere. For example, pebbles and rounded boulders at the landing site indicated that they were formed by running water in the distant past of Mars. The mission was also able to observe icy water clouds in the planet’s lower atmosphere. Moreover, the radio tracking provided an accurate measurement of the probe’s location, Mars’ rotation pole, and information about its metallic core.
The Mars Pathfinder mission made its final transmission on September 27, 1997, after which both the Pathfinder probe and Sojourner were left on the surface of the Red Planet. But the mission’s legacy continues to contribute to and shape human space exploration and science 25 years after its successful landing on Mars.