All good things come to an end and the European Space Agency’s Herschel
Space Observatory mission is no exception. After more than three years
in orbit, the most powerful infrared telescope ever flown in space has
ceased scientific operations after the last of the liquid helium used to
supercool its instruments ran out.Launched from the Guiana Space Center in French Guiana on 14 May, 2009 atop an Ariane 5 rocket, the Herschel was sent into what is called a Lissajous orbit 1,500,000 kilometers (930,000 miles) from Earth. In such an orbit, the spacecraft circles, not the Earth, but the Lagrangian point L2 – a spot where the gravitational forces of the Earth, Moon and Sun balance out.
