NASA utilized the Mars Global Surveyor (MGS), a robotic spacecraft that had been orbiting Mars since 1997, to capture detailed images of the Martian landscape. On December 6, 2006, the agency announced that the images obtained from MGS revealed intriguing dark streaks appearing on the slopes of craters and canyons in the southern hemisphere. Scientists, including those involved with the MGS mission, suggested that these streaks could be indicators of salty liquid water flowing on the surface during warm seasons on Mars, thereby revolutionizing the understanding of Martian hydrology.

Previous missions to Mars had hinted at the presence of water, but the MGS images provided compelling evidence that hinted at a more dynamic landscape than previously thought. The images captured by MGS allowed researchers to study geological features and analyze the surface composition of Mars in unprecedented detail. This finding was part of a long-standing quest to ascertain whether life ever existed on the red planet, given that liquid water is crucial for life as we know it.

The investigations into Mars's surface conditions also opened a floodgate of questions surrounding the planet's climate history and evolution. The MGS data became foundational for subsequent missions, such as the Phoenix and Curiosity rovers, which continued to seek more clues about water and potential habitats for life on Mars.