TUCSON, June 7 (UPI) -- NASA's Phoenix Mars Lander is having trouble placing Martian soil samples into research instruments, project officials in Arizona say.
Ray Arvidson, the top scientist of the University of Arizona-based team, said while the robotic device has gathered some soil, the team has been unable to confirm it has been deposited inside the lander's laboratory instruments, a NASA news release said Saturday.
The project official said the problem may be due to the makeup of the soil, which could be too large to fit through the instruments' screens.
"I think it's the cloddiness of the soil and not having enough fine granular material," said Arvidson said.
"In the future, we may prepare the soil by pushing down on the surface with the arm before scooping up the material to break it up, then sprinkle a smaller amount over the door," he added.
Arvidson said future soil-gathering efforts will likely be focused at the site of one of the Lander's earlier digs.
"We are hoping to learn more about the soil's physical properties at this site," he said. "It may be more cohesive than what we have seen at earlier Mars landing sites."