News | December 5, 2016
 
Curiosity Rover Team Examining New Drill Hiatus
View from the Navigation Camera (Navcam) on the mast of NASA's Curiosity Mars
Rover
 
This Dec. 2, 2016, view from the Navigation Camera (Navcam) on the mast of
NASA's Curiosity Mars Rover shows rocky ground within view while the rover was
working at an intended drilling site called "Precipice" on lower Mount Sharp.
 
Credit: NASA/JPL-Caltech
Full image and caption
 
http://www.jpl.nasa.gov/spaceimages/details.php?id=PIA21140
 
NASA's Curiosity Mars rover is studying its surroundings and monitoring the
environment, rather than driving or using its arm for science, while the rover
team diagnoses an issue with a motor that moves the rover's drill.
 
Curiosity is at a site on lower Mount Sharp selected for what would be the
mission's seventh sample-collection drilling of 2016. The rover team learned
Dec. 1 that Curiosity did not complete the commands for drilling. The rover
detected a fault in an early step in which the "drill feed" mechanism did not
extend the drill to touch the rock target with the bit.
 
"We are in the process of defining a set of diagnostic tests to carefully
assess the drill feed mechanism. We are using our test rover here on Earth to
try out these tests before we run them on Mars," Curiosity Deputy Project
Manager Steven Lee, at NASA's Jet Propulsion Laboratory in Pasadena,
California, said Monday. "To be cautious, until we run the tests on Curiosity,
we want to restrict any dynamic changes that could affect the diagnosis. That
means not moving the arm and not driving, which could shake it."
 
Two among the set of possible causes being assessed are that a brake on the
drill feed mechanism did not disengage fully or that an electronic encoder for
the mechanism's motor did not function as expected. Lee said that workarounds
may exist for both of those scenarios, but the first step is to identify why
the motor did not operate properly last week.
 
The drill feed mechanism pushes the front of the drill outward from the turret
of tools at the end of Curiosity's robotic arm. The drill collects powdered
rock that is analyzed by laboratory instruments inside the rover. While arm
movements and driving are on hold, the rover is using cameras and a
spectrometer on its mast, and a suite of environmental monitoring capabilities.
 
At the rover's current location, it has driven 9.33 miles (15.01 kilometers)
since landing inside Mars' Gale Crater in August 2012. That includes more than
half a mile (more than 840 meters) since departing a cluster of scenic mesas
and buttes -- called "Murray Buttes" -- in September 2016. Curiosity has
climbed 541 feet (165 meters) in elevation since landing, including 144 feet
(44 meters) since departing Murray Buttes.
 
The rover is climbing to sequentially higher and younger layers of lower Mount
Sharp to investigate how the region's ancient climate changed, billions of
years ago. Clues about environmental conditions are recorded in the rock
layers. During its first year on Mars, the mission succeeded at its main goal
by finding that the region once offered environmental conditions favorable for
microbial life, if Mars has ever hosted life. The conditions in long-lived
ancient freshwater Martian lake environments included all of the key chemical
elements needed for life as we know it, plus a chemical source of energy that
is used by many microbes on Earth.
 
Curiosity's drill, as used at all 15 of the rock targets drilled so far,
combines hammering action and rotating-bit action to penetrate the targets and
collect sample material. The drilling attempt last week was planned as the
mission's first using a non-percussion drilling method that relies only on the
drill's rotary action. Short-circuiting in the percussion mechanism has
occurred intermittently and unpredictably several times since first seen in
February 2015.
 
"We still have percussion available, but we would like to be cautious and use
it for targets where we really need it, and otherwise use rotary-only where
that can give us a sample," said Curiosity Project Scientist Ashwin Vasavada
at JPL.
 
JPL, a division of Caltech in Pasadena, California, manages NASA's Mars
Science Laboratory Project for NASA's Science Mission Directorate, Washington,
and built the project's rover, Curiosity. For more information about the
mission, visit:
 
http://mars.jpl.nasa.gov/msl/
 
News Media Contact
Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.webster@jpl.nasa.gov
 
2016-309
 
 
Regards,
 
Roger

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