NASA remembers July 4 Mars milestone that made its rovers possible

NASA is remembering one of its most notable July 4th events: the arrival of its Sojourner on Mars in 1997. Depending on your age, you may not be familiar with Sojourner, having instead learned about Curiosity, the now-defunct Opportunity, and perhaps even the Spirit rover, which was active on the Red Planet from 2004 to 2010. Lesser known is the space agency's Sojourner, a rover that paved the way for NASA's latest and greatest Mars missions.

With yet another Independence Day upon us, NASA is remembering its Sojourner mission and its successes. The rover arrived on Mars back on July 4, 1997, via the space agency's Mars Pathfinder mission. According to NASA, this mission 'served as the foundation' for the Mars rovers still operating on the planet today, as well as the upcoming Perseverance (Mars 2020) rover.

Using what was, at the time, an innovative pedal system alongside its airbag landing system, NASA's Pathfinder successfully landed Sojourner on the Martian surface, where the rover spent 83 days — not very long compared to modern missions, but substantially longer than the seven days NASA had anticipated for its little rover.

In addition to taking measurements on the Red Planet, Sojourner also captured 550 photos while the Pathfinder lander captured another approximately 16,500 images. The mission provided researchers on Earth with 'extensive data' on Martian weather, including the planet's winds, according to the space agency.

An image captured by Pathfinder of Sojourner (above) shows the advances NASA has made in its space photography in only a handful of decades. The space agency is gearing up to launch yet another rover to the Red Planet — Perseverance — which will carry its own milestone innovation: a helicopter, the first of its kind that will be deployed on another planet.