Herschel carries the largest space telescope ever launched to date. From a point in space called the 2nd Lagrangian Point (or L2), its 3.5-metre diameter mirror will collect long-wavelength infrared radiation from some of the coolest and most distant objects in the Universe. Herschel will cover a wide range of wavelengths, from the far-infrared to the sub-millimetre band. The longest of these wavelengths have never been covered before. The mission is to be launched in spring 2009 in tandem with ESA's Planck spacecraft, on board an Ariane-5 rocket from Europe's Spaceport in Kourou (French Guyana).