The GERB is the Geostationary Earth Radiation Budget instrument on board the European Space Agency's Meteostat Second Generation (MSG) satellite. MSG-1 launched from French Guiana in 2002 with a GERB on board; the next two GERBs are awaiting launch at this time.

GERB is intended to measure the Earth's radiation budget, measuring the difference between radiation that comes from the sun and the amount that is re-radiated back into space. GERB is able to measure both shortwave and longwave radiation.