Scientists had a chance to practice a family reunion of sorts. As FIDO
looked up in the sky with its Mini-TES instrument, the Mars Global
Surveyor (MGS) orbiter "flew overhead" with TES looking
down toward the rover.
In reality, MGS was 250 million miles away orbiting Mars, but scientists
were practicing for an opportunity that will come up during the Mars
Exploration Rover mission. Near 2 o'clock some afternoon on Mars, MGS
will fly overhead aiming its instruments at the rover's landing site.
Mini-TES will look up toward the oncoming spacecraft. While looking at
each other, both instruments will study the Martian atmosphere.
Both TES and Mini-TES were designed by Arizona State University's
Phil Christensen to measure the types of minerals on Mars as well as to
study the Martian atmosphere. TES was designed over 18 years ago
and has been actively used for studying Mars for almost 5 years.
Mini-TES will join its older sibling in order to get a detailed look at
the Martian surface.
"Beyond the extraordinary science this opportunity will
provide, what I think is really neat about this is that two spacecraft will
be able to take thermal pictures of each other at Mars," says
Christensen. "The TES instrument was created in 1986, and in
2004, it may take a picture of a newer version of itself." The
kind of thermal picture Christensen means is similar to those taken
by "night-vision" goggles or infrared cameras.
For FIDO, the challenge was similar to what scientists will face while
operating the Rovers on Mars. The team wanted to drive the FIDO rover
to the south, get around a cliff wall, and look into the next valley. Time
was running out, so the need to drive was urgent. Planners realized the
importance of this unique opportunity to coordinate the two
"spacecraft," so the drive was shortened just enough to
allow a chance to stop and use the Mini-TES and to take other
needed observations of the atmosphere.
Getting the coordinated observations into the FIDO plans was a
challenge in itself. The opportunity was not a part of the original plan
for the test. However, scientists recognized the extra opportunity to
practice for a real mission challenge and lobbied to get the TES
observations-just as they will have to during Mars operations.
"At first we all laughed at the thought of bringing MGS and TES
into the FIDO field test," said Texas A&M's Mark Lemmon, "but
it was too great an opportunity to pass up. It was difficult working out a
plan to use Mini-TES at the same moment TES would be looking at us
without losing valuable time to travel and meet our mission requirements.
It pushed us hard to learn how to best use the rover, and that's what
the test is for."