Opportunity Prepares To Move While Spirit Sits
Like any new arrival grabbing all the attention, NASA engineers
were thrilled to watch, the Opportunity rover sent home its first
color snapshot from Mars.
However, engineers reported Monday that its ailing twin, Spirit,
seemed to be suffering from a problem trying to manage too many
files.
Sounds like the ANN office [OK, Art... I heard
that.--E-I-C]
Spirit has spent 23 Martian days, or "sols," on the red planet, the
last five or so without much activity, while Opportunity has
completed two and will spend a week or two moving cautiously
through the steps required for it to stand up and roll off onto
Mars' terra firma.
The team at the Jet Propulsion Laboratory is increasingly
convinced that Spirit's problem has a remedy, possibly related to
the memory systems and their inability to manage an unexpected
accumulation of files that built up during the robot's seven-month,
300 million-mile cruise from Earth.
In a press conference, mission manager Jennifer Trosper
described in detail the steps by which the team progressed from
last Wednesday's angst-inducing breakdown to today's hopeful
prognosis, finding clues from the few snippets of transmitted data.
"In the last week, my favorite image is the one where the signal
went from a flat line to a beep," she said.
At one point, the rover sent data "from the year 2053," she
said. ". . . There weren't a lot of scenarios that would put us in
2053 on Mars."
Engineers temporarily
disabled the computer's flash memory, which is similar to the
system used by digital cameras to retain photographs whether the
power is on or off. Trosper said one theory is that Spirit's
random-access memory, or RAM, has too little capacity to manage the
file buildup in the flash memory.
As many of us do with our own personal computers, NASA engineers
plan to ease the burden on the rover's data collection and storage
system by deleting hundreds of the unnecessary files. The
Opportunity team will take a measure of prevention handlers will
see to it that any similar backlog in Opportunity's memory is also
purged.
The team expects that Spirit could be back in operation in two
or three weeks, but Trosper said it is not yet clear whether it can
be fully restored. "It's kind of like we have a patient in rehab,
and we are nursing her back to health."
Spirit is sitting in a Connecticut-size bowl called Gusev
Crater, the possible site of an ancient lake. Opportunity is
halfway around the planet on a vast flat equatorial plain called
Meridiani, where an orbiting U.S. spacecraft earlier detected a
large deposit of a mineral called hematite, which on Earth usually
forms in association with water.
"We're looking out back across a pretty spectacular landscape,"
said Jim Bell, also of Cornell University, leader of the rovers'
panoramic-camera team.
The image shows the lander's nesting place inside a shallow
crater about the size of a school auditorium.