Begins Analysis on Deepest Soil Sample on Mars
(NASA/JPL) — 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 observing movement of clouds overhead.
of clouds captured by the Phoenix lander on Mars. Particles
of water-ice make up these
clouds, like ice-crystal cirrus
clouds on Earth. Ice hazes have been common at the
Phoenix site in recent days. The clouds are a dramatic
visualization of the Martian water cycle. The water
vapor comes off the north pole during
the peak of summer. The northern-Mars summer has just passed
its peak water-vapor abundance at the Phoenix site. The
atmospheric water is available to form into clouds, fog
and frost, such as the lander has been observing recently.
of Arizona/Texas A&M
lander’s robotic arm on Sunday sprinkled a small fraction of
50 cubic centimeters of soil that had been scooped up from
the informally named "Stone Soup" trench on Saturday,
the 95th day of the mission. The Stone Soup trench, in the
left portion of the lander’s active workspace, is approximately
18 centimeters (7 inches) deep.
is pretty exciting stuff and we are anxious to find out what
makes this deeper soil cloddier than the other samples," said
Doug Ming, a Phoenix science team member from NASA’s Johnson
Space Center, Houston.
of the vast arctic plain where Phoenix landed on May 25 bears
a pattern of polygon-shaped small hummocks, similar to some
permafrost terrain on Earth. Scientists are particularly interested
in the new sample because it is the first delivered to an analytical
instrument from a trench on the margin between two of the polygons,
where different material may collect than what has been analyzed
from near the center of a polygon. Seen inside Phoenix’s scoop
Sunday, the sample material from the bottom of the trench displayed
clumping characteristics somewhat different from other cloddy
soil samples that have been collected and examined.
of images of fresh soil dug and discarded from Stone Soup trench
have given some clues to the composition of the sample. While
spectral observations have not produced any sign of water-ice,
bigger clumps of soil have shown a texture that could be consistent
with elevated concentration of salts in the soil from deep
in the trench. The lander’s wet chemistry laboratory can identify
soluble salts in the soil.
team has also been studying a movie created from still pictures
of the nearby Martian sky showing dramatic water ice clouds
moving over the landing site during a 10-minute period on Sol
94 (Aug. 29).
images were taken as part of a campaign to see clouds and track
wind. These are clearly ice clouds," said Mark Lemmon,
the lead scientist for the lander’s surface stereo imager,
from Texas A&M University.