Sentinel 1B ist am 23.12.2021 wegen eines Problems mit der Energieversorgung ausgefallen:
Copernicus Sentinel-1B is unavailable since 23 December 2021 at 06:53 UTC, no data are being generated.
Following the related news of 23 December 2021, detailed investigations have taken place. Specific actions will be performed over the next days to implement an onboard configuration change that will prevent the re-occurrence of the anomaly (that could result in satellite safety risks).
This requires simulations and system validation activities on ground, before upload to the satellite.
This satellite unavailability period may potentially last up to 2 weeks, however all efforts to shorten this unavailability are being deployed.
[https://scihub.copernicus.eu/news/News00977]
Der erste Optimismus, das Problem beheben zu können, ist wohl verflogen. Beim Wiederhochfahren hat sich gezeigt, dass die Ursachen tiefer liegen. Sieht nach einem ernsteren Problem aus. Immerhin hat man wohl noch genug Energie für die anderen Systeme, nicht aber für den Betrieb des Radar:
Following the previous news on the Sentinel-1B anomaly that occurred on 23 December 2021, the resuming of the operations was carefully prepared including the on-board configuration changes preventing the anomaly to occur again.
However, during the preparation of the recovery operations, it became clear that the initial anomaly was a consequence of a potential serious problem related to a unit of the power system of the Sentinel-1B satellite. The operations performed over the last days did not allow to reactivate so far a power supply function required for the radar operations.
[https://scihub.copernicus.eu/news/News00980]
Im Netz wird über den Einschlag eines Trümmers des russischen ASAT-Tests spekuliert. Anhaltspunkte, wie eine plötzliche Lage-/Bahnänderung, wurden aber nicht berichtet. Also wohl eher unwahrscheinlich.