Mars Pathfinder and Sojourner Rover Land

On July 4, 1997, NASA's Mars Pathfinder bounced to a landing on Mars using innovative airbags, then deployed Sojourner — a 23-pound, microwave-oven-sized rover that became the first wheeled vehicle to operate on another planet. Built under NASA's "faster, better, cheaper" philosophy, the mission cost just $265 million — a fraction of Viking's budget. Sojourner analyzed Martian rocks with its Alpha Proton X-ray Spectrometer and roamed the landing site for 83 days, far exceeding its 7-day design life. The mission's website received over 500 million hits — a record at the time — demonstrating massive public interest in Mars exploration. Pathfinder proved that Mars could be explored affordably and set the template for the Spirit, Opportunity, and Curiosity rovers.