NASA about to pull plug on Mars rover Opportunity, which has been silent for 8 months

Workers put final touches to Spirit and Opportunity Mars exploration rovers at NASA Jet Propulsion Laboratory (JPL) in 2003. Spirit and Opportunity are identical rovers. (Photo by David McNew/Getty Images)

CAPE CANAVERAL, Fla. (AP) -- NASA is trying one last time to contact its record-setting Mars rover Opportunity, before calling it quits.

The rover has been silent for eight months, victim of an intense dust storm. Thick dust darkened the sky last summer and, for months, blocked sunlight from the spacecraft's solar panels.

NASA said Tuesday it will issue a final series of recovery commands. If there's no response by Wednesday -- which NASA suspects will be the case -- Opportunity will be declared dead, 15 years after arriving at Mars. The rover is the longest-lasting lander on the red planet.

Team members are already looking back at Opportunity's achievements, including confirmation that water once flowed on Mars. Besides endurance, the six-wheeled rover set a roaming record of 28 miles (45 km).