After extending the mission of the venerable Mars Rover Opportunity another time, NASA announced that it will drive down a gully dug by a fluid a long time ago, maybe by water. The goal is to understand whether this is the remains of an ancient Martian river. It’s the beginning of yet another mission for Opportunity, which suffers wear and might be at risk because of a storm that will hit Mars.
The new adventure of the Mars Rover Opportunity begins in the area called “Bitterroot Valley” of the western side of Endeavour Crater, a basin with a diameter of 22 kilometers (14 miles) which is actually an impact crater generated a few billion years ago. Opportunity reached this crater’s rim in 2011 after exploring for years other smaller craters in which it found traces of acidic water in the underground layers and occasionally even on the surface.
According to plans, the Mars Rover Opportunity will descend along the gully until it reaches the bottom of the Endeavour crater. Another goal of this new mission extension is comparing samples of this crater’s rocks with those examined in the previously explored plains. Sulfate-rich rocks are expected to be found and it will be interesting to see if they are of the same type found outside the crater.
Scientists believe that they were formed by a process related to the presence of water so identifying their nature with precision will help reconstruct the area’s geological history. This is also the point of the mission extension’s third goal, which is to find rocks from a geological layer earlier to the impact that created Endeavour Crater. At the moment it’s not possible to know if Opportunity will be able to find such ancient rocks.
In recent days, the Mars Rover Opportunity has been studying rocks close to “Spirit Mound”, near Bitterroot Valley’s eastern border. It arrived there coming from the area called “Marathon Valley”, where it spent the previous mission extension. Among the places of the valley there’s “Wharton Ridge”, named in memory of the astrobiologist Robert A. Wharton, who passed away in 2012.
There’s excitement for this new mission extension but also concern for the Mars Rover Opportunity’s wear and for the conditions it could face. In the coming months on Mars a global dust storm could set off that could create problems to Opportunity. While the other active rover on the Red Planet, Curiosity, uses a radioisotope generator to get energy, the old Opportunity uses solar panels so a sandstorm is a risk.
In these cases, the Mars Rover Opportunity limits its activity to save energy and in extreme cases uses the little it receives only to avoid cooling down to temperatures that would deactivate it off forever. If it survives this storm, it can pass 13 Earth years of activity.