It was 25 years ago on Independence Day when a small rover named after a Civil War abolitionist parachuted and crashed to the surface of the red planet with airbags.
NASA’s first-ever Mars rover, named Sojourner, landed on its Pathfinder lander at Chryse Planitia on July 4, 1997. The pair of spacecraft ushered in a revolution in Mars exploration technology that NASA’s Curiosity and Perseverance rovers are continuing to this day, a quarter century later.
The Pathfinder Rover name has been chosen (opens in new tab) from a nationwide competition won by Valerie Ambroise, 12, whose winning essay discussed the importance of Sojourner Truth, aka Isabella Van Wagener. (Now the essay winner appears to be a real estate agent in Connecticut.)
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The Sojourner rover’s namesake spent nearly four months – 12 times its projected lifespan – on Mars, snuggling up against rocks, analyzing their chemistry and relaying its observations back to Earth.
The results, broadcast in real-time on early internet networks, revealed a red planet potentially habitable for life: “Resulting scientific evidence suggests that Mars has historically been warm and wet, with water residing in its liquid condition and thicker was atmosphere,” said NASA’s Jet Propulsion Laboratory (JPL) in California, which managed the rover (opens in new tab) the mission.
Today, Sojourner serves as a key solar-powered ancestor for NASA’s much larger, nuclear-powered rovers of today: Curiosity (just before its 10th Earth Anniversary on Mars) and Perseverance (which landed on February 18, 2021 accompanied by the first-ever Martian helicopter, Ingenuity .)
These rovers are part of a generational network of landers, orbiters and other vehicles exploring the red planet to understand its complex history. Why the Martian atmosphere thinned, how much water spilled onto the surface, and whether habitable conditions existed are questions that still plague scientists today.
25 years ago today, a real pioneer landed. Sojourner proved we can drive on Mars; Since then, each rover has made true overland surveys. I’m the fifth in this line, collecting specimens that could one day return to Earth and rewrite history. Continue. pic.twitter.com/ikLdrPOc7cJuly 4, 2022
The Mission also served as a guiding light in public engagement. Today’s rover teams use tweets, TikTok, and live streams to announce new discoveries about Mars.
In the much earlier 1997 internet, images were frequently uploaded to the Pathfinder website, which still retains its pre-millennial design today. At first, NASA thought it would get 25 million downloads after landing; That estimate was quickly updated by three times, the agency recalled (opens in new tab) in 2017. The traffic load forced other agency servers to step in to avoid website crashes at NASA’s Jet Propulsion Laboratory, but it all worked.
Pathfinder proved so popular in the public mind that it was a pivotal turning point in 2015’s The Martian, a Hollywood film (sponsored by NASA and based on a novel by Andy Weir) about an astronaut , who after his death embarks alone on the red planet stranded.
The mission made its last transmission on September 27, 1997, leaving both Pathfinder and Sojourner silent on the surface, but their data will remain essentially forever. NASA still has 16,500 images from Pathfinder and 550 images from Sojourner that modern scientists can analyze to gain new insights into the history of the red planet.