Giotto (spacecraft)

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 spacecraft succeeded in approaching Halley's nucleus at a distance of 596 kilometers. It 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 in the Scrovegni Chapel. 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 Giottos fly-by, but they in turn fell through with the Challenger disaster. The plan then became a cooperative armada of five space probes 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 the spacecraft colliding at very high speed with the many dust particles from the comet. The coordinated group of probes became known as the Halley Armada. The cylindrical spacecraft was 1.85 m in diameter and had three internal platforms. It was derived from the GEOS research satellite built by British Aerospace in Filton, Bristol, and modified with the addition of a dust shield (Whipple shield) as proposed by Fred Whipple. The shield comprised a thin (1 mm) aluminium sheet separated by a space and a thicker (12 mm) Kevlar sheet. The later Stardust spacecraft would use a similar Whipple shield.