STARDUST Status Report
September 15, 2000
There were two Deep Space Network
(DSN) tracking passes during the past week. All subsystems onboard the spacecraft
are performing normally.
A Medium Gain Antenna (MGA) DSN pass used the Solid State Power
Amplifier (SSPA) 1 and did not show a power drop. During the
previous two MGA DSN passes (early August) the SSPA 1 exhibited its
3db drop in power output that was observed a year ago. At that time,
root cause was thought to be due to trapped charge particles
accumulating on one of the floating point gate array (FPGA) chips.
The SSPA operation was changed from leaving the SSPA on continuously
to power cycling between DSN tracking passes to stop the gain. When this
power cycling stratety was adopted the 3db power drop ceased. The
investigation has been re-opened with an emphasis on SSPA temperature
since during the pass on Saturday the SSPA temperature was slightly
cooler than the two previous passes.
Five Navigation Camera (NAVCAM) images were taken using five
different mirrors. Each image had a minimum of three 6th magnitude
stars in the field of view. These images will be used to determine
any improvements to the NAVCAM performance since the CCD heater test.
With the current DSN scheduling, it will take approximately two weeks to
transmit the images stored onboard the spacecraft to Earth.
Plans are being developed to perform another NAVCAM CCD heater test, with
one change that would include turning on the Navigation Mirror heater
to raise the overall temperature in the optical path.
For more information on the STARDUST mission - the first ever
comet sample return mission - please visit the STARDUST home page: