Phoenix Mars Lander Digs Deeper as Third Month Nears End

August 26, 2008
Digging by NASA's Phoenix Mars Lander on Aug. 23, 2008, during the 88th sol (Martian day) since landing, reached a depth about three times greater than in any trench Phoenix has excavated. Image credit: NASA/JPL-Caltech/University of Arizona/Texas A&M University

(PhysOrg.com) -- The next sample of Martian soil being grabbed for analysis is coming from a trench about three times deeper than any other trench NASA's Phoenix Mars Lander has dug.

On Tuesday, Aug. 26, the spacecraft will finish the 90 Martian days (or "sols") originally planned as its primary mission and will continue into a mission extension through September, as announced by NASA in July. Phoenix landed on May 25.

"As we near what we originally expected to be the full length of the mission, we are all thrilled with how well the mission is going," said Phoenix Project Manger Barry Goldstein of NASA's Jet Propulsion Laboratory, Pasadena, Calif.

Phoenix's main task for Sol 90 is to scoop up a sample of soil from the bottom of a trench called "Stone Soup," which is about 18 centimeters, or 7 inches deep. On a later sol, the lander's robotic arm will sprinkle soil from the sample into the third cell of the wet chemistry laboratory. This deck-mounted laboratory, part of Phoenix's Microscopy, Electrochemistry and Conductivity Analyzer (MECA), has previously used two of its four soil-testing cells.

"In the first two cells we analyzed samples from the surface and the ice interface, and the results look similar. Our objective for Cell 3 is to use it as an exploratory cell to look at something that might be different," said JPL's Michael Hecht, lead scientist for MECA. "The appeal of Stone Soup is that this deep area may collect and concentrate different kinds of materials."

Stone Soup lies on the borderline, or natural trough, between two of the low, polygon-shaped hummocks that characterize the arctic plain where Phoenix landed. The trench is toward the left, or west, end of the robotic arm's work area on the north side of the lander.

When digging near a polygon center, Phoenix has hit a layer of icy soil, as hard as concrete, about 5 centimeters, or 2 inches, beneath the ground surface. In the Stone Soup trench at a polygon margin, the digging has not yet hit an icy layer like that.

"The trough between polygons is sort of a trap where things can accumulate," Hecht said. "Over a long timescale, there may even be circulation of material sinking at the margins and rising at the center."

The science team had considered two finalist sites as sources for the next sample to be delivered to the wet chemistry lab. This past weekend, Stone Soup won out. "We had a shootout between Stone Soup and white stuff in a trench called 'Upper Cupboard,'" Hecht said. "If we had been able to confirm that the white material was a salt-rich deposit, we would have analyzed that, but we were unable to confirm that with various methods."

Both candidates for the sampling location offered a chance to gain more information about salt distribution in the Phoenix work area, which could be an indicator of whether or not liquid water has been present. Salt would concentrate in places that may have been wet.

While proceeding toward delivery of a sample from Stone Soup into the wet chemistry laboratory, Phoenix is also using its Thermal and Evolved-Gas Analyzer to examine a soil sample collected last week from another trench, at a depth intermediate between the surface and the hard, icy layer.

Provided by NASA

Explore further: Phoenix Mars Lander Explores Site by Trenching

Related Stories

Phoenix Mars Lander Explores Site by Trenching

August 21, 2008

NASA's Phoenix Mars Lander scientists and engineers are continuing to dig into the area around the lander with the spacecraft's robotic arm, looking for new materials to analyze and examining the soil and ice subsurface structure.

Phoenix Mission Conducting Extended Activities on Mars

September 1, 2008

NASA's Phoenix Mars Lander, having completed its 90-day primary mission, is continuing its science collection activities. Science and engineering teams are looking forward to at least another month of Martian exploration.

Phoenix Lander Finishes Soil Delivery to Onboard Labs

October 22, 2008

(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 ...

Analysis Begins on Deepest Martian Soil Sample

September 2, 2008

(PhysOrg.com) -- Scientists have begun to analyze a sample of soil delivered to NASA's Phoenix Mars Lander's wet chemistry experiment from the deepest trench dug so far in the Martian arctic plains. Phoenix has also been ...

Recommended for you

Bright areas on Ceres suggest geologic activity

December 13, 2017

If you could fly aboard NASA's Dawn spacecraft, the surface of dwarf planet Ceres would generally look quite dark, but with notable exceptions. These exceptions are the hundreds of bright areas that stand out in images Dawn ...

Major space mystery solved using data from student satellite

December 13, 2017

A 60-year-old mystery regarding the source of some energetic and potentially damaging particles in Earth's radiation belts is now solved using data from a shoebox-sized satellite built and operated by University of Colorado ...

Spanning disciplines in the search for life beyond Earth

December 13, 2017

The search for life beyond Earth is riding a surge of creativity and innovation. Following a gold rush of exoplanet discovery over the past two decades, it is time to tackle the next step: determining which of the known exoplanets ...

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

trippingsock
1 / 5 (2) Aug 26, 2008
They've just wasted their money...

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.