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Eutelsat’s OneWeb constellation went down for 48 hr. after its ground segment, maintained by Hughes Network Systems, was not programed so that 2024 was a 366-day-long leap year.
The calendar error caused the “manual calculation for the GPS to UTC offset,” Eutelsat said on Jan. 3. UTC is Coordinated Universal Time, a precision time standard used for communication and navigation systems as well as scientific research, among other applications.
The Y2K-esque problem meant that internet users of OneWeb’s low-Earth-orbit communications satellites experienced a 48-hr. outage starting at midnight on Dec. 30.
“The root cause was identified as a software issue within the ground segment,” Eutelsat said on Jan. 2. “Eutelsat was fully mobilized and worked with the vendor to restore full service, while maintaining a constant dialogue with affected customers. The constellation is operating nominally once again.”
The health of OneWeb’s satellites was not affected by the ground segment error, the company notes. Eutelsat says Hughes Network worked around the clock to fix the problem and the network was 80% restored by Jan. 1 and 100% back online by Jan. 2.