Travelers In The Night

When the NASA WISE spacecraft ran out of frozen hydrogen, its detectors warmed up, and it was no longer able to conduct its primary mission. It was placed in a hibernation mode and left to orbit the Earth in silence. A couple of years ago NASA engineers figured out that the spacecraft, even with warm detectors, could find some interesting asteroids and decided to wake it up. The WISE spacecraft in turn has produced data on more than15,000 solar system objects including more than 350 Earth approaching asteroids and 60 comets.