The Infrared Astronomical Satellite (IRAS) was a joint project of the US, UK and the Netherlands. The IRAS mission performed an unbiased, sensitive all sky survey at 12, 25, 60 and 100 µm. IRAS increased the number of catalogued astronomical sources by about 70%, detecting about 350,000 infrared sources. IRAS discoveries included a disc of dust grains around the star Vega, six new comets, and very strong infrared emission from interacting galaxies as well as wisps of warm dust called infrared cirrus which could be found in almost every direction of space. IRAS also revealed for the first time the core of our galaxy, the Milky Way.