20 years ago today, the Mars Pathfinder rover, Sojourner, landed on the Red Planet.
Named for abolitionist and women’s rights activist Sojourner Truth, NASA’s Sojourner rover landed on Mars on July 4, 1997. Unlike previous landing systems that used conventional rockets to decelerate, the Sojourner rover used a parachute and a system of airbags to slow down before the rover dropped roughly 100 feet to the planet’s surface. This system comprised of the Pathfinder lander, which was renamed the Carl Sagan Memorial Station after successfully delivering the rover. Sagan, a major proponent of the exploration of Mars, passed away shortly after the Mars Pathfinder mission launched on its way to the Red Planet.
Sojourner then set about its mission to analyze nearby rocks on the surface. Compositional analysis revealed that silica was found in higher concentrations in rocks than the surrounding area. Being found in igneous rocks, such a presence of silica was a hint that Mars may have had a more interesting geological history than was previously thought. Sojourner also sent pictures of the Martian surface back to NASA, while Pathfinder took photographs of the Martian sky. Among the photos from Sojourner were images showing rounded pebbles and conglomerate rocks indicating that different types of soil had been mixed in the past—evidence of a formerly water-rich planet.
Originally scheduled to operate for 7 sols (1 sol is about 40 minutes longer than a day on Earth), Sojourner had the possibility of extending its mission to 30 sols. In total, Sojourner operated for 83 sols before communications were lost on September 27, 1997. In that time, it covered just over 100 meters of the Martian surface.
Learn more about Sojourner here: https://www.nasa.gov/feature/jpl/why-no-one-under-20-has-experienced-a-day-without-nasa-at-mars
Here’s to another 20 years exploring the surface of Mars!
