Back Graphite-Epoxy Motor Catalan Graphite-Epoxy Motor Czech Graphite-Epoxy Motor French GEM 40 Galician Graphite-Epoxy Motor Italian GEM (ロケットモータ) Japanese Graphite-Epoxy Motor Dutch Graphite Epoxy Motor Polish Motor grafite-epóxi Portuguese Graphite-Epoxy Motor Slovak
The Graphite-Epoxy Motor (GEM) is a family of solid rocket boosters developed in the late 1980s and used since 1990. GEM motors are manufactured with carbon-fibre-reinforced polymer casings and a fuel consisting of HTPB-bound ammonium perchlorate composite propellant. GEM is produced by Northrop Grumman Space Systems. GEM boosters are used on the Atlas V and were previously used on the Delta II, Delta III, and Delta IV launch vehicles. A new variant, the GEM 63XL, flew as part of the Vulcan Centaur launch vehicle on 8 January 2024.