The Helios 2 system includes Helios 2A and Helios 2B, both of which are European military observation satellites used by France, Belgium, Spain and Greece. Helios 2A was launched on December 18, 2004 by an Ariane 5 rocket from French Guiana. Helios 2B was launched five years later on December 18, 2009, carried also by an Ariane 5. The two satellites are identical. They carry a Thales-built high-resolution visible and thermal infrared instrument with 35 cm resolution, and an Airbus-built medium-resolution instrument.