Phoenix Scrapes 'Almost Perfect' Icy Soil for Analysis

Samples hold clues to history of Martian water, climate and possible habitability.
July 1, 2008
This image was acquired by NASA's Phoenix Mars Lander's Robotic Arm Camera on the 35th Martian day of the mission, or Sol 34 (June 29, 2008). This image shows the trench informally called "Snow White 5." The trench is 4-to-5 centimeters (about 1.5-to-1.9 inches) deep, 24 centimeters (about 9 inches) wide and 33 centimeters (13 inches) long.

Snow White 5 is Phoenix's current active digging area after additional trenching, grooming, and scraping by Phoenix's Robotic Arm in the last few sols to trenches informally called Snow White 1, 2, 3, and 4. Near the top center of the image is the Robotic Arm's Thermal and Electrical Conductivity Probe.

Snow White 5 is located in a patch of Martian soil near the center of a polygonal surface feature, nicknamed "Cheshire Cat." The digging site has been named "Wonderland."

This image has been enhanced to brighten shaded areas.
This image was acquired by NASA's Phoenix Mars Lander's Robotic Arm Camera on the 35th Martian day of the mission, or Sol 34 (June 29, 2008). This image shows the trench informally called "Snow White 5." The trench is 4-to-5 centimeters (about 1.5-to-1.9 inches) deep, 24 centimeters (about 9 inches) wide and 33 centimeters (13 inches) long. Snow White 5 is Phoenix's current active digging area after additional trenching, grooming, and scraping by Phoenix's Robotic Arm in the last few sols to trenches informally called Snow White 1, 2, 3, and 4. Near the top center of the image is the Robotic Arm's Thermal and Electrical Conductivity Probe. Snow White 5 is located in a patch of Martian soil near the center of a polygonal surface feature, nicknamed "Cheshire Cat." The digging site has been named "Wonderland." This image has been enhanced to brighten shaded areas.

NASA's Phoenix Mars Lander enlarged the "Snow White" trench and scraped up little piles of icy soil on Saturday, June 28, the 33rd Martian day, or sol, of the mission. Scientists say that the scrapings are ideal for the lander's analytical instruments.

The robotic arm on Phoenix used the blade on its scoop to make 50 scrapes in the icy layer buried under subsurface soil. The robotic arm then heaped the scrapings into a few 10- to 20-cubic centimeter piles, or piles each containing between two and four teaspoonfuls. Scraping created a grid about two millimeters deep.

The scientists saw the scrapings in Surface Stereo Imager images on Sunday, June 29, agreed they had "almost perfect samples of the interface of ice and soil," and commanded the robotic arm to pick up some scrapings for instrument analysis.

The scoop will sprinkle the fairly fine-grained material first onto the Thermal and Evolved-Gas Analyzer, or TEGA. The instrument has tiny ovens to bake and sniff the soil to assess its volatile ingredients, such as water. It can determine the melting point of ice.

Phoenix's overall goals are to: dig to water frozen under subsurface soil, touch, examine, vaporize and sniff the soil and ice to discover the history of water on Mars, determine if the Martian arctic soil could support life and study Martian weather from a polar perspective.

The Phoenix mission is led by Peter Smith of The University of Arizona with project management at JPL and development partnership at Lockheed Martin, located in Denver. International contributions come from the Canadian Space Agency; the University of Neuchatel, Switzerland; the universities of Copenhagen and Aarhus, Denmark; Max Planck Institute, Germany; and the Finnish Meteorological Institute.