NASA's AIM spacecraft retires after 15 years of studying Earth's clouds.

NASA's AIM spacecraft, which was launched in 2007 to study noctilucent clouds, has gone silent after a battery power failure. The spacecraft had been sending a significant amount of data back to Earth until recently. The AIM team will monitor the spacecraft for another two weeks in case it reboots. The spacecraft's data has appeared in 379 peer-reviewed papers, including a recent study that found human-driven climate change is causing night-shining clouds to form more frequently.