Spirale

SPIRAL ( " Système Préparatoire Infra - Rouge pour l' Alerte " ) is the name for two French test satellites, to validate a future infrared early warning system, manufactured by EADS as prime contractor and Thales Alenia Space as a developer on behalf of France's defense procurement agency DGA.

The two satellites SPIRAL A and B were started as an additional payload on 11 February 2009 by an Ariane 5 together with the satellite Hot Bird 10 and NSS -9 and placed on a highly elliptical orbit (600 x 36,000 km at 2 ° orbital inclination ). With them, the provision and use of a system for infrared imaging of structures on the Earth and its analysis and the establishment of an early-warning chain is to be demonstrated.

Specifications

The cube-shaped satellites dreiachsstabilisierten based on the satellite bus MYRIADE the French space agency CNES have a size of 60 x 60 x 85 inches and are equipped with a dual-segment solar panel made ​​of gallium arsenide solar cells with 160 watts of power and a lithium ion battery. The heavy when you start depending 117.3 kg satellite has a power consumption of 80 watts in standby and 100 watts at the image capture. For image acquisition using satellite infrared telescopes with active cooling system. The position control is via four reaction wheels, two MTBs ( magneto- torquer bars ) and four small Hydrazintriebwerke with one Newton thrust. For orientation, they are fitted with a star sensor, three sun sensors and three gyros.