Wind satellite survives vacuum
ESA's Aeolus satellite has been particularly tricky to build. One of the main stumbling blocks has been getting its lasers to work in a vacuum, but recent tests on the satellite show that the vacuum or temperature of space won't get in the way of Aeolus measuring Earth's winds.
Aeolus carries one of the most sophisticated instruments ever to be put into orbit: ALADIN, with two powerful lasers, a large telescope and very sensitive receivers.
It shoots pulses of ultraviolet light down into the atmosphere and measures the backscattered signals from molecules and aerosols to profile the world's winds.