Spirit's high-gain antenna successfully deployed
BY WILLIAM HARWOOD
STORY
WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION
Posted:
January 5, 2004
In another major milestone, the Spirit Mars rover's high-gain
antenna was successfully deployed Sunday night and aimed at Earth. A few minutes
before 12:30 a.m. EST today, the first direct-to-Earth communications session over
the high-data-rate antenna began, prompting a now-familiar round of cheers and applause
in mission control at the Jet Propulsion Laboratory in Pasadena, Calif.
The
X-band antenna is critical for Spirit's mission. Flight controllers plan to beam
commands directly to the high-gain antenna every morning to tell the rover what to
do. Science data from the rover can be beamed back through the high-gain or through
NASA's Mars Global Surveyor and Mars Odyssey orbiters.
This illustration
of the Mars Exploration Rover shows the lollipop-shaped high-gain antenna. Credit:
NASA/JPL
During the first communications session early today, engineers
successfully established a two-way link, uplinking commands and downlinking science
data, including more pictures that were stored in the rover's computer. A so-called
"postcard" from Mars, a seven-frame color mosaic taken by Spirit's panoramic
camera was expected to be downlinked later in the evening. If all goes well, the
picture will be released during a news briefing at noon.
In the meantime,
more low-resolution black-and-white Navcam images were downlinked, a series of pictures
that will be stitched together into a panorama to help engineers judge how Spirit's
mostly collapsed landing airbags change shape as daily heating and cooling affects
trapped gases. Engineers are trying to determine what, if anything, needs to be done
to further retract sections of partially inflated airbags that might block one or
more of Spirits possible exit routes off the lander.