Since 2004, original interviews, original reporting, and the only regularly published news feature documenting NASA’s first overland expedition of the Red Planet through the adventures and discoveries of Opportunity, Spirit, and the MER team, by A.J.S. Rayl. If you're new to the mission or want a list of all our resources, check out our MER mission page.
Perched on the southern wall of Marathon Valley at Endeavour Crater, Opportunity braved temperatures descending well below -100° F in December to work the winter science campaign and home in on the remnants of ancient clays.
Opportunity faced the challenges of winter as well as technological issues in November, but pressed on, hiking up hill and into a geological treasure trove that may well present the scientists with the evidence they need to solve the clay mineral mystery of Marathon Valley.
Opportunity continued her walkabout around Marathon Valley in September and sent home more evidence of significant water alteration and, perhaps, an ancient environment inviting enough for the emergence of life.
Opportunity drove farther into Marathon Valley in August, dug into what appears to be a water-altered rock, and took a lot of picture postcards in what is turning out to be a distinctively different site from any that the mission has found since the robot field geologist landed in 2004.
After three weeks of being in a communications blackout on the other side of the Sun during the Earth-Mars solar conjunction, Opportunity phoned home, reporting that she is healthy and ready to continue her mission.
Opportunity spent a mostly merry month of May on Mars touring Spirit of St. Louis Crater, stopping at science targets named in honor of Charles Lindbergh and the incredible flight he took 88 years ago.
After investigating some flat, light and dark toned rocks around Spirit of St. Louis Crater in April, Opportunity chalked up another milestone achievement – the 4000th sol or Martian day of surface operations.
MER mission ops team members joined other engineers and scientists, some who previously worked on the MER mission, to take on the challenge of a relay marathon to celebrate Opportunity's milestone achievement.
Our Mars Exploration Rovers (MER) update has recorded the journeys of the twin rovers Spirit and Opportunity on the surface of Mars since their arrival in January of 2004. It is a treasure trove of information, insight, and high-quality reporting detailing every step of this unprecedented voyage of discovery.