On this day in 2013 – April 29th – ESA's Herschel Space Observatory mission ended.
The infrared observatory was named after William Herschel, who discovered infrared radiation, and his sister and collaborator Caroline Herschel. The observatory was able to see the coldest and dustiest objects in space, but it needed liquid helium to cool its instruments. When that ran out, the mission ended.
Last edited by Mona - Astronomy; 05/01/1808:52 PM.