Mars Exploration Rover

Artist's conception of MER rovers on Mars
MER imaged from different angles

NASA's Mars Exploration Rover (MER) mission was a robotic space mission involving two Mars rovers, Spirit and Opportunity, exploring the planet Mars. It began in 2003 with the launch of the two rovers to explore the Martian surface and geology; both landed on Mars at separate locations in January 2004. Both rovers far outlived their planned missions of 90 Martian solar days: MER-A Spirit was active until March 22, 2010,[1] while MER-B Opportunity was active until June 10, 2018.[2]

  1. ^ mars.nasa.gov. "Rover Update: 2010: All". mars.nasa.gov. Retrieved February 14, 2019.
  2. ^ Strickland, Ashley (February 13, 2019). "After 15 years, the Mars Opportunity rover's mission has ended". CNN. Retrieved February 14, 2019.