The Geostationary Earth Radiation Budget (GERB[1]) is an instrument aboard EUMETSAT's Meteosat Second Generation geostationary satellites designed to make accurate measurements of the Earth radiation budget. It was produced by a European consortium consisting of the United Kingdom, Belgium and Italy. The first, known as GERB 2, was launched on 28 August 2002 on an Ariane 5 rocket. The second, GERB 1, was launched on 21 December 2005, and the third, GERB3, on 5 July 2012. The last GERB 4 device was launched 14 July 2015. The first launched GERB 2 on MSG 1 is currently situated over the Indian Ocean at 41.5°E, while GERBs 1 and 3 on MSG 2 and 3 are still located over the standard Africa EUMETSAT position. GERB 4 on MSG is yet to become operational.