Giotto mission

Giotto

Artist's concept of Giotto spacecraft
Operator	European Space Agency
COSPAR ID	1985-056A
SATCAT no.	15875
Website	Official Site at ESA.int
Spacecraft properties
Launch mass	582.7 kg (1,285 lb)
Power	196 W
Start of mission
Launch date	11:23:00, July 2, 1985 (1985-07-02T11:23:00)
Rocket	Ariane 1
Launch site	Guiana Space Centre
End of mission
Deactivated	July 23, 1992 (1992-07-23)
Orbital parameters
Reference system	Heliocentric
Eccentricity	0.17334
Perihelion	0.73 AU
Apohelion	1.04 AU
Inclination	2.09°
Period	304.6 days
Epoch	10 July 1992, 15:18:43 UTC
Flyby of Comet Halley
Closest approach	14 March 1986
Distance	596 km (370 mi)
Flyby of Earth
Closest approach	2 July 1990
Distance	22,730 km (14,120 mi)
Flyby of Comet Grigg-Skjellerup
Closest approach	10 July 1992
Distance	200 km (120 mi)
Legacy ESA insignia for the Giotto mission

Giotto was a European robotic spacecraft mission from the European Space Agency. The spacecraft flew by and studied Halley's Comet and in doing so became the first spacecraft to make close up observations of a comet. On 13 March 1986, the mission succeeded in approaching Halley's nucleus at a distance of 596 kilometers. The spacecraft was named after the Early Italian Renaissance painter Giotto di Bondone. He had observed Halley's Comet in 1301 and was inspired to depict it as the star of Bethlehem in his painting Adoration of the Magi.

Originally a United States partner probe was planned that would accompany Giotto, but this fell through due to budget cuts at NASA. There were plans to have observation equipment on board a Space Shuttle in low-Earth orbit around the time of Giotto's fly-by, but they in turn fell through with the Challenger disaster.

The plan then became a cooperative armada of five spaceprobes including Giotto, two from the Soviet Union's Vega program and two from Japan: the Sakigake and Suisei probes. The idea was for Japanese probes and the pre-existing American probe International Cometary Explorer to make long distance measurements, followed by the Russian Vegas which would locate the nucleus, and the resulting information sent back would allow Giotto to precisely target very close to the nucleus. Because Giotto would pass so very close to the nucleus ESA was mostly convinced it would not survive the encounter due to bombardment from the many high speed cometary particles. The coordinated group of probes became known as the Halley Armada.