Published on 20 May 2019
Europe's Aeolus satellite was launched last year to gather data to improve weather forecasts, and its observations have unquestionably proved their worth. But the space laser is now degrading and has already lost half its power.
Engineers plan to switch Aeolus to its back-up light source in June to see what difference this could make.
If the same issues arise, the UK-assembled spacecraft may not be able to complete the minimum three years expected of the mission.
"We're losing strength in the outgoing power of about 1 millijoule per week," said Dr Josef Aschbacher, the director of Earth observation at the European Space Agency (ESA). "We don't know why. We have some speculations but that's all. That's the bad news; the good news is that despite the degrading laser, the quality of the wind data is fantastic."