The European Space Agency’s Aeolus – Earth Explorer Atmospheric Dynamics Mission – for wind profile monitoring is in trouble as the spacecraft’s main wind measurement instrument, using Lidar, has a faulty laser.

The laser is now degrading at a rate of 1 milli-joule per week and has already lost half its power. Engineers plan to switch Aeolus to its back-up light source in June. If this fix does not work, it will end the mission earlier than its three-year planned lifespan.

Artist’s impression of ADM-Aeolus in orbit. Courtesy: ESA