The GOES-West weather satellite has returned to service after being down yesterday due to an anomaly. Initially known as GOES-17, and GOES-S before that, an on-board computer reset triggered by the satellite forced it into a safe-hold mode at 1:37 am ET yesterday. In this phase, all of GOES-17’s instruments were automatically turned off. This morning, NOAA announced that GOES-17 is out of safe-hold mode and that engineers expect its six instruments to return to normal operations soon.
GOES-17 is no stranger to technical failures. A United Launch Alliance (ULA) Atlas V rocket brought the GOES-S satellite to space for NASA and NOAA on the evening of March 1, 2018. The picture-perfect launch brought the latest satellite in the Geostationary Operational Environmental Satellite (GOES)-R series of satellites to orbit. After reaching orbit, the GOES-S was re-named to GOES-17. After a check-out period that was to extend through this spring, GOES-17 was to go into service as GOES-West and provide the Pacific and western United States with coverage to compliment GOES-East, which is doing the same for the Atlantic and eastern United States.
During this check-out phase of the satellite before it became operational, program specialists identified a significant malfunction with the Advanced Baseline Imager. The issue affects 13 of the infrared and near-infrared channels on the instrument, which has a total of 16 channels. A team of experts from NOAA, NASA, the ABI contractor team and industry investigated the issue and pursued multiple courses of possible corrective actions.
The problem has to do with the plumbing for the cooling system that keeps the imager’s infrared detectors sufficiently chilled. Stephen Volz, NOAA’s assistant administrator for satellite and information services at the time, told reporters that the glitch is a “serious problem” during a conference call. “This is the premier Earth-pointing instrument on the GOES platform, and 16 channels, of which 13 are infrared or near-infrared, are important elements of our observing requirements, and if they are not functioning fully, it is a loss. It is a performance issue we have to address”, said Volz.
By the time the satellite became operational in November 2019, most of the satellite’s capability was restored. Work had been done to reduce and/or work-around flawed data coming from the satellite. “The GOES-17 ABI is now projected to deliver more than 97 percent of the data it was designed to provide, a testament to the skill and dedication of the engineers and all the GOES project team members,” said Stephen Volz, Ph.D., director, NOAA’s Satellite and Information Service. “We are confident the GOES constellation will continue to meet the needs of forecasters across the country.”
According to NOAA, the probable cause of yesterday’s anomaly appears to be a memory bit error in the spacecraft computer. NOAA’s engineering team says the computer has been responding correctly to commands. As part of restoration of service, earlier this morning, the Advanced Baseline Imager and Magnetometer were restored and data are flowing. In a statement, NOAA said, “The team expects some minor, short-term data quality issues while the instruments are being recalibrated, but GOES-17 is on track for a full recovery with no lasting effects to the satellite.”
