[meteorite-list] NASA's Phoenix Mars Lander Puts Soil in Chemistry Lab, Team Discusses Next Steps

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Thu, 26 Jun 2008 16:31:58 -0700 (PDT)
Message-ID: <200806262331.QAA06737_at_zagami.jpl.nasa.gov>

June 25, 2008

Dwayne Brown
Headquarters, Washington
202-358-1726
dwayne.c.brown at nasa.gov

Guy Webster
Jet Propulsion Laboratory, Pasadena, Calif.
818-354-6278
guy.webster at jpl.nasa.gov

Sara Hammond
University of Arizona, Tucson
520-626-1974
shammond at lpl.arizona.edu

RELEASE: 08-160

NASA'S PHOENIX MARS LANDER PUTS SOIL IN CHEMISTRY LAB, TEAM DISCUSSES NEXT STEPS

TUCSON, Ariz. -- NASA's Phoenix Mars Lander placed a sample of Martian
soil in the spacecraft's wet chemistry laboratory today for the first
time. Results from that instrument, part of Phoenix's Microscopy,
Electrochemistry and Conductivity Analyzer, are expected to provide
the first measurement of the acidity or alkalinity of the planet's
soil.

The analysis of this and other soil samples will help researchers
determine whether ice beneath the soil ever has melted, and whether
the soil has other qualities favorable for life.

The Phoenix team is discussing what sample to deliver next to the
lander's other analytical instrument, which bakes and sniffs soil to
identify volatile ingredients. Engineers have identified possible
problems in the mechanical and electrical operation of that
instrument, the Thermal and Evolved-Gas Analyzer, or TEGA.

Scientists are studying information provided by TEGA's analysis of the
first Martian soil sample put in that instrument. The instrument has
eight single-use oven cells; each cell can analyze one sample. When
doors for a second TEGA oven were commanded open last week, the doors
opened only partway. Later, the team determined that mechanical
interference may prevent doors on that oven and three others from
opening fully. The remaining three ovens are expected to have one
door that opens fully and one that opens partially, as was the case
with the first oven used.

"The tests we have done in our test facility during the past few days
show the robotic arm can deliver the simulated Martian soil through
the opening with the doors in this configuration," said William
Boynton of the University of Arizona, Tucson, lead scientist for
TEGA. "We plan to save the cells where doors can open wider for
accepting ice samples."

Scientists believe the first soil sample delivered to TEGA was so
clumpy that soil particles clogged a screen over the opening. Four
days of vibration eventually succeeded at getting the soil through
the screen. However, engineers believe the use of a motor to create
the vibration may also have caused a short circuit in wiring near
that oven. Concern about triggering other short circuits has prompted
the Phoenix team to be cautious about the use of other TEGA cells.

Subsequent soil samples for TEGA will be delivered with a different
method than the first. The newer method will sprinkle soil into the
instrument to make it easier for particles to get through the
screens.

The Phoenix mission is led by Peter Smith at the University of Arizona
with project management at NASA's Jet Propulsion Laboratory in
Pasadena, Calif., and the development partnership at Lockheed Martin
in Denver. International contributions are 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.

For more information about the mission, visit:

http://www.nasa.gov/phoenix

        
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Received on Thu 26 Jun 2008 07:31:58 PM PDT