PASADENA, Calif. — Two more attempts to regain contact with NASA's Mars Global Surveyor spacecraft failed this week.

The 10-year-old probe last had radio communication with Earth on Nov. 2, and NASA said earlier this week that the spacecraft's mission to map the surface of the Red Planet was likely at an end.

But efforts to find out if the orbiting spacecraft was still working continued, including transmitting commands for Mars Global Surveyor to send signals to the NASA rover Opportunity operating on the surface of Mars.

The rover did not detect any signals from MGS during attempts Tuesday and Wednesday, according the Web site for NASA's Jet Propulsion Laboratory, which manages the mission.

MGS has been the longest and most productive mission to Mars, sending more than 240,000 images back to Earth, according to the space agency.

The spacecraft was launched Nov. 7, 1996, for what was planned as a two-year mapping mission.