The Herschel ATLAS is the largest key astronomical project awarded on ESA's Herschel Space Observatory as an Open Time survey.

We have been awarded 600 hours of time on Herschel to survey an huge area of the sky (a whopping 550 square degrees), four times larger than all the other Herschel extragalactic surveys combined.  We will use both the PACS and SPIRE cameras which take pictures in infra-red and submillimetre light at wavelengths of 100um, 160um, 250um, 350um, and 500um.   Why Herschel? It is the largest, most powerful infrared telescope ever flown in space and is the first space observatory to observe from the far-infrared to the submillimetre waveband, unveiling the mysterious hidden cold Universe to us for the first time. It will explore further in the far-infrared than any previous mission, studying otherwise invisible dusty and cold regions of the cosmos, both near and far, at a level of detail that has not been seen before. 

With our Herschel survey, we expect to detect approximately 250,000 galaxies from the nearby Universe out to redshifts of 3 to 4, when the Universe was only a few billion years old. There have been many successful surveys of the nearby Universe at optical wavelengths, which have given us a detailed understanding of the stars in galaxies and how they evolve. Herschel-ATLAS is the first such survey at far-infrared and submillimetre wavelengths and will give us a new insight into galaxies -  telling us about the stars which are hidden by dust and the gas from which new stars may form in the future.