High Quality Content by WIKIPEDIA articles! The Herschel Space Observatory is a European Space Agency space observatory sensitive to the far infrared and submillimetre wavebands (55-672 microns). It is the largest infrared space telescope ever launched, carrying a single mirror of 3.5 metres (11.5 ft) in diameter. Herschel is in its final months, it is hoped its coolant will last until March 2013.