Herschel will carry the largest space telescope ever launched to date. From a point in space called the 2nd Lagrangian Point (or L2), its 3.5-m diameter mirror will collect long-wavelength infrared radiation from some of the coolest and most distant objects in the Universe. Herschel will be the only space observatory to cover the range from far-infrared to sub-millimetre wavelengths. The mission is to be launched in July 2008, in tandem with ESA's Planck spacecraft, by an Ariane-5 rocket from Europe's Spaceport in Kourou (French Guiana).