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Are there
organic compounds or signs of past or present life on Mars? The top meter is
dry and irradiated. But we have
still only dug (with Phoenix in 2007) about 20cm, and the small drill on the
Curiosity rover is only 5cm long.
It is the Mars subsurface, of a meter or more deep, where we expect to
find any preserved life-signatures and past climate history. So, we need a drill that can retrieve
material at depths of 1m or more.
Given the lightspeed time delays, a drill on Mars must be autonomous,
very different from how drilling is done on Earth.
The “Icebreaker”
mission concept is to return to Mars to an area with subsurface ice layers in
the first 1m depth, either at the polar latitudes (first visited by the Phoenix
mission in 2007-08) or mid-latitudes (Viking). The Icebreaker payload could be
mounted on a modified Phoenix spacecraft bus or on a rover, and carry an
automated 1m rotary-percussive drill, the SOLID life-detection instrument, an Alpha
Particle X-Ray Spectrometer (APXS) and JPL’s Wet Chemistry Lab, together
capable of detecting organics in the presence of perchlorates or other strong
oxidants. The automated Icebreaker
drill captures downhole materials in the bottom 10cm of its drill string and
raises these to the surface where they are mechanically removed and transferred
to on-deck instruments.

Artist's concept of the Icebreaker drill and sample transfer system, mounted on a Phoenix-derived Mars lander platform.
Planetary
drilling and sampling beyond the Moon requires intelligent and autonomous
systems. Unlike terrestrial
drills, the Icebreaker drill will work without injected drilling muds or
lubricants, blind (with no prior local or regional seismic or other surveys
beyond Phoenix’s excavations), and weak (very low [200N] downward force or
weight on bit, and perhaps 100W power available). Given the 7-20 minute lightspeed transmission delays to
Mars, while drilling faults manifest in terms of seconds, the Icebreaker drill
cannot be controlled directly from Earth.
Therefore highly reliable automated operations will be necessary, with
the ability to safe the drilling system and recover from almost any downhole
fault condition on its own.
The
Phoenix arm was able to reach and scrape the ground ice but was unable to
penetrate it significantly.
Sampling deeper into the ground ice to acquire materials deposited
during warmer climates requires a drill. The Icebreaker drill was designed and
built by Honeybee Robotics. We
have tested both rotary-drag and rotary-percussive drill designs in laboratory
chamber tests and in field tests at Mars analog sites These have been in turn
used to validate and test the controls and drill health management software
necessary for Icebreaker automated drilling and sampling operations.
Over the
past four years, our Icebreaker team has developed the rotary-percussive drill
hardware, the automated controls for the drill, and integrated these with a
sample-transfer arm to instruments on a mockup spacecraft deck. A dry run in at Haughton Crater in the
Canadian Arctic in July 2012 showed that these could work together to acquire
and convey subsurface samples to on-board instruments for analysis.
The
technology objective of this field season is to repeat these integrated tests
in a higher-fidelity, more difficult Mars analog site, in the Dry Valleys of
Antarctica, and to continue to improve the reliability and fault-tolerance of
the whole drilling and sample acquisition system.
NASA’s Astrobiology
Science and Technology for Exploring Planets (ASTEP) program supports
investigations that focus on exploring Earth’s extreme environments to learn
how best to search for life on other planets. A related effort called the Astrobiology
Science and Technology Instrument Development (ASTID) program supports the
development and testing of new technologies to enable the search for life
outside Earth’s biosphere.
Icebreaker is an umbrella project supported by both ASTEP and ASTID to
both develop sample-acquisition technologies and incorporate these in investigations
in extreme environments.
This field
season, our team of seven will be comprised of three NASA Ames researchers
(Alfonso Davila, Margarita Marinova, and myself), a Honeybee Robotics drill
engineer (Bolek Mellerowicz), two university co-investigators (Wayne Pollard of
McGill University, Denis Lacelle of the University of Ottawa) and a graduate
student (Jacqueline Goordial of McGill University).
Alfonso
Davila departed for Antarctica in December and has been at McMurdo Station for
a couple of weeks, serving as our advance liaison there. The rest of the team departed North
America on 29 December 2012 and are now in Christchurch,
New Zealand waiting for weather and aircraft availability for the next leg down
to McMurdo. We have been told that
the ice runway at McMurdo Station has been too warm – hence mushy – for aircraft
to depart to return to the Antarctic deployment center at Christchurch, New
Zealand, So we have had to wait several days longer than expected in
Christchurch (which locals abbreviate as “Chch”).

Arriving In Christchurch... The US Antarctic Center buildings are visible, along with a NY Air National Guard C-130.
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