Phoenix Lander Digs and Analyzes Soil as Darkness Gathers

(PhysOrg.com) -- As fall approaches Mars' northern plains, NASA's Phoenix Lander is busy digging into the Red Planet's soil and scooping it into its onboard science laboratories for analysis.

Over the past two weeks, Phoenix's nearly 2.4-meter-long (8 feet) arm moved a rock, nicknamed "Headless," about 0.4 meters (16 inches), and snapped an image of the rock with its camera. Then, the robotic arm scraped the soil underneath the rock and delivered a few teaspoonfuls of soil onto the lander's optical and atomic-force microscopes. These microscopes are part of Phoenix's Microscopy, Electrochemistry and Conductivity Analyzer (MECA).

Scientists are conducting preliminary analysis of this soil, nicknamed "Galloping Hessian." The soil piqued their interest because it may contain a high concentration of salts, said Diana Blaney, a scientist on the Phoenix mission with NASA's Jet Propulsion Laboratory, Pasadena, Calif.

As water evaporates in arctic and arid environments on Earth, it leaves behind salt, which can be found under or around rocks, Blaney said. "That's why we wanted to look under 'Headless,' to see if there's a higher concentration of salts there."

More digging is underway. Phoenix scientists want to analyze a hard, icy layer beneath the Martian soil surface, and excavating to that icy layer underneath a rock might give scientists clues about processes affecting the ice.

So the robotic arm has dug into a trench called "La Mancha," in part to see how deep the Martian ice table is. The Phoenix team also plans to dig a trench laterally across some of the existing trenches in hopes of revealing a cross section, or profile, of the soil's icy layer.

"We'd like to see how the ice table varies around the workspace with the different topography and varying surface characteristics such as different rocks and soils," said Phoenix co-investigator Mike Mellon of the University of Colorado, Boulder. "We hope to learn more about how the ice depth is controlled by physical processes, and by looking at how the ice depth varies, we can pin down how it got there."

Over the weekend, on the 128th Martian day, or sol, Phoenix engineers successfully directed the robotic arm to dig in a trench called "Snow White" in the eastern portion of the lander's digging area. The robotic arm then delivered the material to an oven screen on Phoenix's Thermal and Evolved-Gas Analyzer.

The Phoenix team will try to shake the oven screen so the soil can break into smaller lumps and fall through for analysis.

The Phoenix lander, originally planned for a three-month mission on Mars, is now in its fifth month. As fall approaches, the lander's weather instruments detect diffuse clouds above northern Mars, and temperatures are getting colder as the daylight hours wane.

Consequently, Phoenix faces an increasing drop in solar energy as the sun falls below the Martian horizon. Mission engineers and scientists expect this power decline to curtail activities in the coming weeks. As darkness deepens, Phoenix will primarily become a weather station and will likely cease all activity by the end of the year.

Provided by NASA

Related stories:

Phoenix Mars Lander Enters Safe Mode
(PhysOrg.com) -- NASA'S Phoenix Mars Lander entered safe mode late yesterday in response to a low-power fault brought on by deteriorating weather conditions. While engineers anticipated that a fault could occur due to the diminishing power supply, the lander also unexpectedly switched to the "B" side of its redundant electronics and shut down one of its two batteries.
Phoenix Mars Mission Faces Survival Challenges
(PhysOrg.com) -- In a race against time and the elements, engineers with NASA's Phoenix Mars Lander mission hope to extend the lander's survival by gradually shutting down some of its instruments and heaters, starting today.
Phoenix Lander Finishes Soil Delivery to Onboard Labs
(PhysOrg.com) -- NASA's Phoenix Mars Lander has finished scooping soil samples to deliver to its onboard laboratories, and is now preparing to analyze samples already obtained. Scientists are anxious to analyze the samples as the power Phoenix generates continues to drop. The amount of sunlight is waning on Mars' northern plains as late-summer turns to fall.
Phoenix Gets Bonus Soil Sample
(PhysOrg.com) -- The Mars Phoenix Lander's robotic arm successfully delivered soil into oven six of the lander's thermal and evolved-gas analyzer (TEGA) on Monday, Oct. 13, or Martian day (sol) 137 of the mission.
Phoenix Weathers Dust Storm
(PhysOrg.com) -- The Phoenix Lander over the weekend successfully weathered a regional dust storm that temporarily lowered its solar power, and the team is back investigating the Red Planet's northern plains.
Mars Lander Sees Falling Snow, Soil Data Suggest Liquid Past
(PhysOrg.com) -- NASA's Phoenix Mars Lander has detected snow falling from Martian clouds. Spacecraft soil tests experiments also have provided evidence of past interaction between minerals and liquid water, processes that occur on Earth.
Looking for water on Mars
NASA's Phoenix Scout Lander reached Mars on May 25,, opened a soils lab, and started looking for water. Phoenix uses a robotic scoop arm to deliver regolith samples to the suite of instruments aboard the Lander--with one exception. The thermal and electrical conductivity probe designed by a team of research scientists at Decagon Devices Inc. is actually mounted on the robotic arm and makes direct contact with the regolith. It measures thermal conductivity, thermal diffusivity, electrical conductivity, and dielectric permittivity of the regolith, as well as vapor pressure of the air.
Phoenix Lander Might Peek Under a Rock
(PhysOrg.com) -- If the robotic arm on NASA's Phoenix Mars Lander can nudge a rock aside today, scientists on the Phoenix team would like to see what's underneath.

News discussion:

Space & Earth science news