Important notice about STEREO Behind
The STEREO Ahead observatory is currently performing as expected, and taking
science data on a regular basis.
On September 23, the STEREO Ahead spacecraft detected a power spike on the
electronics shared by the IMPACT and PLASTIC instruments, and autonomously
powered them down. This is believed to be due to a single event upset. A
similar event occured in September 2011. Recovery operations are proceeding.
Most of the IMPACT functionality has been restored, and PLASTIC is expected to
resume operations over the next few days.
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. On Sunday, August 21, 2016,
contact was reestablished with the STEREO Behind spacecraft for the first time
in 22 months. However, no signal has been received since September 23, 2016,
which indicates that the spacecraft's orbital motion has carried it to a
position where either the low gain antennae cannot currently communicate with
Earth, or the solar panels are not sufficiently illuminated. Follow
for more information.
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: Tuesday, 02-Oct-2018 18:45:55 GMT
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