White material, possibly ice, is located only at the upper portion of the trench, indicating that it is not continuous throughout the excavated site

The U.S. Space Agency NASA says it believes its Phoenix Mars lander may have uncovered bits of ice on the planet.

NASAsays the lander's robotic arm dug a trench in the Martian arctic June15, exposing bits of a bright material that were photographed.

Thedice-size crumbs completely disappeared over the course of a few days,leading investigators to believe that the material was frozen waterthat vaporized after it was exposed.

The mission's leadinvestigator, Peter Smith, said the material's disappearance "is perfect evidence that it's ice."

The agency initiallybelieved the bright material may have been salt, but Smith said saltwould not have evaporated as the material did.

The Phoenix probe landed on Mars on May 25.

Itwas designed to use its onboard laboratories to test Martian soil tolearn the history of water on the planet and to look for the presenceof organic compounds.