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› Full SizeA Sampling of Martian Soils
This collage shows the variety of soils found at landing sites on Mars. The elemental composition of the typical, reddish soils were investigated by NASA's Viking, Pathfinder and Mars Exploration Rover missions, and now with the Curiosity rover, using X-ray spectroscopy. The investigations found similar soil at all landing sites. In addition, the soil was usually unchanged over the traverse across the Martian terrain made by both Mars Exploration Rovers.The Mars Exploration Rover Spirit's landing region in Gusev Crater is seen in both pictures at top; Viking's landing site is shown at lower left; and a close-up of Curiosity's Gale Crater soil target called "Portage" is at lower right.
In Gusev Crater, several white subsurface deposits were excavated with Spirit’s wheels and found to be either silica-rich or hydrated ferric sulfates.
Image credit: NASA/JPL-Caltech
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› Full SizeCuriosity's 'Rocknest' Workplace
NASA's Curiosity Mars rover
documented itself in the context of its work site, an area called
"Rocknest Wind Drift," on the 84th Martian day, or sol, of its mission
(Oct. 31, 2012). The rover worked at this location from Sol 56 (Oct. 2,
2012) to Sol 100 (Nov. 16, 2012).
The drift consists of sand trapped on the downwind side of a group of dark cobbles the team named Rocknest. This mosaic of 55 images from the Mars Hand Lens Imager (MAHLI) shows the first four of five places from which the rover’s scoop obtained sand to clean the sample handling and processing system. The scooped material was ultimately delivered to the Chemistry and Mineralogy Experiment (CheMin) and the Sample Analysis at Mars (SAM) laboratory instruments housed inside the rover’s body. The annotated version of this figure shows the location of a scoop taken at a later date -- the fifth and final scoop, and the only one that provided grains delivered to SAM.
Before scooping, the rover team put an approximately 20-inch-wide (about 50- centimeter-wide) wheel print on the Rocknest wind drift. This allowed MAHLI and the Alpha Particle X-Ray Spectrometer (APXS) to determine whether the drift really consisted of sand with small enough sizes to clean the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA) instrument and be delivered to CheMin and SAM. The drift material at the center of the wheel print, named "Portage" by the rover team, was examined by the APXS.
The rover’s robotic arm is not visible in the mosaic because the MAHLI that took this mosaic is on the turret at the end of the arm. Wrist motions and turret rotations on the arm allowed MAHLI to acquire the mosaic's 55 images. An earlier version of the Sol 84 self-portrait was released Nov. 1, 2012 (see PIA16239).
Image credit: NASA/JPL-Caltech/MSSS
The drift consists of sand trapped on the downwind side of a group of dark cobbles the team named Rocknest. This mosaic of 55 images from the Mars Hand Lens Imager (MAHLI) shows the first four of five places from which the rover’s scoop obtained sand to clean the sample handling and processing system. The scooped material was ultimately delivered to the Chemistry and Mineralogy Experiment (CheMin) and the Sample Analysis at Mars (SAM) laboratory instruments housed inside the rover’s body. The annotated version of this figure shows the location of a scoop taken at a later date -- the fifth and final scoop, and the only one that provided grains delivered to SAM.
Before scooping, the rover team put an approximately 20-inch-wide (about 50- centimeter-wide) wheel print on the Rocknest wind drift. This allowed MAHLI and the Alpha Particle X-Ray Spectrometer (APXS) to determine whether the drift really consisted of sand with small enough sizes to clean the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA) instrument and be delivered to CheMin and SAM. The drift material at the center of the wheel print, named "Portage" by the rover team, was examined by the APXS.
The rover’s robotic arm is not visible in the mosaic because the MAHLI that took this mosaic is on the turret at the end of the arm. Wrist motions and turret rotations on the arm allowed MAHLI to acquire the mosaic's 55 images. An earlier version of the Sol 84 self-portrait was released Nov. 1, 2012 (see PIA16239).
Image credit: NASA/JPL-Caltech/MSSS
This is a view of the third (left) and
fourth (right) trenches made by the 1.6-inch-wide (4-centimeter-wide)
scoop on NASA's Mars rover Curiosity in October 2012. Image credit:
NASA/JPL-Caltech/MSSS
› Full image and caption › Related video › Latest images › Curiosity gallery › Curiosity videos
› Full image and caption › Related video › Latest images › Curiosity gallery › Curiosity videos
Scoop Marks in the Sand at 'Rocknest'
This is a view of the third (left) and fourth (right) trenches made by the 1.6-inch-wide (4-centimeter-wide) scoop on NASA's Mars rover Curiosity in October 2012. The image was acquired by the Mars Hand Lens Imager (MAHLI) on Sol 84 (Oct. 31, 2012) and shows some of the details regarding the properties of the "Rocknest" wind drift sand. The upper surface of the drift is covered by coarse sand grains approximately 0.02 to 0.06 inches (0.5 to 1.5 millimeters) in size. These coarse grains are mantled with fine dust, giving the drift surface a light brownish red color. The coarse sand is somewhat cemented to form a thin crust about 0.2 inches (0.5 centimeters) thick. Evidence for the crusting is seen by the presence of angular clods in and around the troughs and in the sharp, jagged indentations and overhangs on one wall of each trench (the walls closest to the top of this figure).Beneath the crust surface, as revealed in the scoop troughs and the piles of sediment on the right side of each, is finer sand, which is darker brown as compared with the dust on the surface. The left end of each trough wall shows alternating light and dark bands, indicating that the sand inside the drift is not completely uniform. This banding might result from different amounts of infiltrated dust, chemical alteration or deposition of sands of slightly different color.
Image credit: NASA/JPL-Caltech/MSSS
› Unannotated version
PASADENA, Calif. - NASA's Mars Curiosity rover has used its full array
of instruments to analyze Martian soil for the first time, and found a
complex chemistry within the Martian soil.
Water and sulfur and chlorine-containing substances, among other
ingredients, showed up in samples Curiosity's arm delivered to an
analytical laboratory inside the rover.
Detection of the substances during this early phase of the mission
demonstrates the laboratory's capability to analyze diverse soil and
rock samples over the next two years. Scientists also have been
verifying the capabilities of the rover's instruments.
Curiosity is the first Mars rover able to scoop soil into analytical
instruments. The specific soil sample came from a drift of windblown
dust and sand called "Rocknest." The site lies in a relatively flat part
of Gale Crater still miles away from the rover's main destination on
the slope of a mountain called Mount Sharp. The rover's laboratory
includes the Sample Analysis at Mars (SAM) suite and the Chemistry and
Mineralogy (CheMin) instrument. SAM used three methods to analyze gases
given off from the dusty sand when it was heated in a tiny oven. One
class of substances SAM checks for is organic compounds --
carbon-containing chemicals that can be ingredients for life.
"We have no definitive detection of Martian organics at this point, but
we will keep looking in the diverse environments of Gale Crater," said
SAM Principal Investigator Paul Mahaffy of NASA's Goddard Space Flight
Center in Greenbelt, Md.
Curiosity's APXS instrument and the Mars Hand Lens Imager (MAHLI) camera
on the rover's arm confirmed Rocknest has chemical-element composition
and textural appearance similar to sites visited by earlier NASA Mars
rovers Pathfinder, Spirit and Opportunity.
Curiosity's team selected Rocknest as the first scooping site because it
has fine sand particles suited for scrubbing interior surfaces of the
arm's sample-handling chambers. Sand was vibrated inside the chambers to
remove residue from Earth. MAHLI close-up images of Rocknest show a
dust-coated crust one or two sand grains thick, covering dark, finer
sand.
"Active drifts on Mars look darker on the surface," said MAHLI Principal
Investigator Ken Edgett, of Malin Space Science Systems in San Diego.
"This is an older drift that has had time to be inactive, letting the
crust form and dust accumulate on it."
CheMin's examination of Rocknest samples found the composition is about
half common volcanic minerals and half non-crystalline materials such as
glass. SAM added information about ingredients present in much lower
concentrations and about ratios of isotopes. Isotopes are different
forms of the same element and can provide clues about environmental
changes. The water seen by SAM does not mean the drift was wet. Water
molecules bound to grains of sand or dust are not unusual, but the
quantity seen was higher than anticipated.
SAM tentatively identified the oxygen and chlorine compound perchlorate.
This is a reactive chemical previously found in arctic Martian soil by
NASA's Phoenix Lander. Reactions with other chemicals heated in SAM
formed chlorinated methane compounds -- one-carbon organics that were
detected by the instrument. The chlorine is of Martian origin, but it is
possible the carbon may be of Earth origin, carried by Curiosity and
detected by SAM's high sensitivity design.
"We used almost every part of our science payload examining this drift,"
said Curiosity Project Scientist John Grotzinger of the California
Institute of Technology in Pasadena. "The synergies of the instruments
and richness of the data sets give us great promise for using them at
the mission's main science destination on Mount Sharp."
NASA's Mars Science Laboratory Project is using Curiosity to assess
whether areas inside Gale Crater ever offered a habitable environment
for microbes. NASA's Jet Propulsion Laboratory in Pasadena, a division
of Caltech, manages the project for NASA's Science Mission Directorate
in Washington, and built Curiosity.
For more information about Curiosity and other Mars missions,
visit: http://www.nasa.gov/mars .
You can follow the mission on Facebook and Twitter
Dwayne Brown Headquarters, Washington
NASA
Guillermo Gonzalo Sánchez Achutegui
ayabaca@gmail.com
ayabaca@hotmail.com
ayabaca@yahoo.com
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