Important notice about reduced STEREO
The STEREO Ahead observatory is back to normal operations on the second side
lobe, including reaction wheel #3. All the instruments have been powered back
on, and producing science data. The IMPACT SWEA and STE instruments are turned
off, and will remain off until the high gain antenna is returned to its main
lobe in November. Because of the current difficulties with commanding due to
solar scintillation effects at such a small separation angle from the Sun, the
SIT instrument is using the original table set that the instrument was launched
with. This table set is known to have some calibration problems, but this is
considered to be better than having no data at all. He intensities are about a
factor of five too low, while the H, O, and Fe intensities are approximately
correct (within a factor of two). The IMPACT team plans to upload the most
current table set when the command link is more stable, which is expected to be
in August. See this important notice for
more information about superior solar conjunction.
Communications with the STEREO Behind spacecraft were interrupted on October 1,
2014 immediately after a planned reset of the spacecraft performed as part of a
test of solar conjunction operations. The spacecraft telemetry indicated an
anomaly in the guidance and control system, but this is still being
evaluated. No further communications have been successful since Oct. 1st.
for more information.
Attempts to reestablish communications with the STEREO Behind spacecraft are
Launched in 2006, the STEREO mission achieved its prime science goals within
the two-year prime mission, but continues to explore solar and heliospheric
activity through the current solar maxmimum and beyond.
Last Revised: Thursday, 23-Jul-2015 10:04:25 EDT
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