Cerise (French for "cherry") was a French military

reconnaissance satellite A reconnaissance satellite or intelligence satellite (commonly, although unofficially, referred to as a spy satellite) is an Earth observation satellite or communications satellite deployed for military or intelligence applications. The ...

. Its main purpose was to intercept HF radio signals for French intelligence services. With a mass of 50 kg, it was launched by an Ariane 4 rocket from Kourou in

French Guiana French Guiana, or Guyane in French, is an Overseas departments and regions of France, overseas department and region of France located on the northern coast of South America in the Guianas and the West Indies. Bordered by Suriname to the west ...

at 17:23 UT, 7 July 1995. Cerise's initial orbital parameters were period 98.1 min, apogee 675 km, perigee 666 km, and

inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ...

98.0 deg. On 24 July 1996 it was hit by

space debris Space debris (also known as space junk, space pollution, space waste, space trash, space garbage, or cosmic debris) are defunct human-made objects in spaceprincipally in Earth orbitwhich no longer serve a useful function. These include dere ...

from the

Ariane 1 Ariane 1 () was the first rocket in the Ariane family of expendable launch systems. It was developed for and operated by the European Space Agency (ESA), which had been formed in 1973, the same year that development of the launcher had commenc ...

rocket that had launched the SPOT 1 satellite. The debris was in a very similar orbit (

orbital inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Earth ...

98.14°) but oriented in such a way that it was going north where Cerise was going south and vice versa. This created a situation of multiple close passes before the actual collision. The objects collided with a relative velocity of 14.8 km/s, about twice the orbital speed of each, over the Indian Ocean. This was the first verified case of an accidental collision between two artificial objects in space, although there had been others "anomalous events" which were probably also collisions. The collision tore off a 2.8-2.9 metre (9.2-9.5 foot) portion of Cerise's gravity-gradient stabilization boom, which left the satellite severely damaged and tumbling with a limited attitude control system. Novel magnetic control algorithms were used to re-stabilise the otherwise undamaged microsatellite to regain almost full operational mission capability. The Naval Space Operations Center detected a minor perturbation in the orbit of the debris of the Ariane rocket.

References

External links

NSSDC Master Catalog - Cerise
Derelict satellites orbiting Earth Satellites of France Spacecraft launched in 1995 Spacecraft launched by Ariane rockets Military equipment introduced in the 1990s Satellite collisions {{france-mil-stub

See also

References

External links