Mars Express Radar to Be Deployed
The European Space Agency's Mars Express orbiter will soon
deploy its radar instrument for the first time. The instrument
is designed to look below the surface of Mars for different
layers of material, most notably water.
Image right: Artist's concept showing how Mars Advanced Radar for
Subsurface and Ionosphere Sounding instrument will look for water. Image credit: ESA
Once the deployment is successful, the Mars Advanced Radar for
Subsurface and Ionosphere Sounding (Marsis) instrument will
complement the orbiter's study of the planet's atmosphere and
surface. The instrument was funded by NASA and the Italian
Space Agency and developed by the University of Rome, Italy, in
partnership with NASA's Jet Propulsion Laboratory, Pasadena,
The instrument's co-principal investigator, Dr. Jeffrey Plaut
of JPL said, "We look forward to the start of the Marsis
experiment, and to becoming full partners in the mission of
discovery that is Mars Express. The radar gives us two ways to
explore the fate of the water that once flowed on the surface
of Mars. We will probe beneath the surface for evidence of
frozen or liquid reservoirs, and we will study the outer
fringes of Mars' atmosphere, where the planet may have lost its
water to space."
The deployment of the three radar booms will take place in
three phases, in a window spanning from May 2 to 12. These
operations will be initiated and monitored from the European
Space Agency's European Space Operations Centre in Darmstadt,
Germany. Each boom will be deployed separately, with the two 20-
meter-long (66-foot-long) dipole booms to be unfurled first and
the 7-meter (23-foot) monopole boom to follow a few days later.
Before each deployment, the spacecraft will be placed in a
'robust' attitude control mode, which will allow it to tumble
freely while the boom extends before regaining standard
pointing to the Sun and Earth.
The result of each deployment can be assessed only after a
series of tests, each taking a few days. After the deployment
of the three booms, European Space Agency engineers will start
the analysis of the complete behavior of the satellite to be
able to confirm the overall success of the operation. The
current schedule is subject to change, due to the timing and
nature of the complex series of operations.
Once deployment is complete, the Marsis instrument will undergo
three weeks of commissioning before the start of actual science
investigations. This timing coincides with the spacecraft's
orbit reaching a favorable position to examine one of the prime
targets for radar observations.
JPL's Richard Horttor, project manager for NASA's roles in the
Mars Express mission, said, "The first data from the radar next
month will signal the success of an innovative international
partnership." Italy provided the instrument's digital
processing system and integrated the parts. The University of
Iowa, Iowa City, built the transmitter for the instrument, JPL
built the receiver and Astro Aerospace, Carpinteria, Calif.,
built the antenna.
JPL is a division of the California Institute of Technology in
Guy Webster (818) 354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
Dolores Beasley (202) 358-1753
NASA Headquarters, Washington