NASA's Mars Exploration Rover Opportunity used its panoramic camera to capture this view of a dark rock that may be an iron meteorite. Part of the rim of Endurance Crater is on the horizon.

The rock, about 45 centimeters (18 inches) wide from this angle, was about 31 meters (102 feet) away from Opportunity when the rover took this picture immediately after an 81-meter (266-foot) drive during the 2,363rd Martian day, or sol, of the rover's mission on Mars.

The rover science team has decided to approach the rock for a closer look, to determine whether it is an iron meteorite as suggested by the dark color, rounded texture and the way it is perched on the surface.

The rock has been given the informal name "Oileán Ruaidh" (pronounced ay-lan ruah), which is the Gaelic name for an island off the coast of northwestern Ireland.

The rim of Endeavor crater, still several kilometers or miles away, has been a long-term destination for Opportunity for about two years. Opportunity landed on Mars in January 2004 for what was planned as a three-month mission.