On January 4, 2004, the Spirit rover embarked on its Martian odyssey to search for signs of past life. An average pace of one centimetre per second may not sound like much, but Spirit was designed for careful observation, not speed. Its mission, initially set for just 90 days, remarkably extended over six years, two months and 19 days (or 3.3 Martian years).

During its tenure, this rover made literal groundbreaking discoveries, like the eruption of an ancient volcano caused by powerful steam from heated underground water. On Earth, these extreme conditions can support microbial life. Thanks to Spirit, astronomers back home learned that Mars was once much wetter than it is today, and gained a much deeper understanding of the Martian wind.