Opportunity was a NASA Mars rover, part of the Mars Exploration Rover mission, that landed in Meridiani Planum on January 25, 2004. Originally designed for a 90‑sol mission, it operated for nearly 15 years—more than 5,000 sols—traversing over 45 km and providing strong evidence that Mars once held liquid water. It ceased communications after a global dust storm in June 2018 and was declared complete in February 2019.
Source: science.nasa.gov
15/08/2003

High-resolution imaging of an area in the Schiaparelli Basin of Mars on June 3 by the MGS Mars Orbiter camera produced this stunning example of layered formations within an old impact crater. On planet Earth, such structures would be seen in sedimentary rock -- material deposited at the bottom of ancient lakes or oceans and then subsequently weathered away to reveal the layers. With the Sun shining from the left, the central layer appears to stand above the others within the 2.3 kilometer wide crater. The crater could well have been filled with water in Mars' distant past, perhaps resting at the bottom of a lake filling the Schiaparelli impact basin. Still, such layers might also have been formed by material settling out of the windy martian atmosphere. As satellites continue to examine the martian surface from orbit, NASA's Spirit and Opportunity spacecraft will attempt to land on on Mars early next year to further explore the tantalizing history of water on the Red Planet.