Earlier this year NASA's Mars Global Surveyor found dark markings on the red planet's south polar cap. Scientists suspect that these markings are formed by violent geysers that erupt during the Martian spring, when frozen carbon dioxide rapidly transforms into gas, as seen in this artist's conception.
NASA researchers are working franticly to reestablish contact with the spacecraft, which disappeared on November 2, but many scientists suspect that the ten-year-old probe has reached the end of its useful life.
"It is an extraordinary machine that has done things the designers never envisioned," Tom Thorpe, project manager for the Mars Global Surveyor at NASA's Jet Propulsion laboratory in Pasadena, California, said in a statement. "The builders and operating staff can be proud of their legacy of scientific discoveries and key support for subsequent missions."