Giotto
Giotto was a European spacecraft that flew past Halley's Comet in 1986 and took the first close images of a comet's nucleus.
Giotto was the European Space Agency's first deep-space mission, named after the Italian painter Giotto di Bondone, who may have painted Halley's Comet as the star of Bethlehem in the early 1300s. Launched in July 1985, it flew past Halley's Comet on 14 March 1986 at a distance of about 600 kilometres.
Giotto revealed that the comet's nucleus was a dark, potato-shaped body about 15 kilometres long, much darker than expected, with jets of gas and dust bursting from a few active areas. A dust particle impact just before closest approach sent the craft spinning briefly, but it survived. In 1992 it went on to fly past a second comet, Grigg–Skjellerup.
Giotto showed that comet dust contains both rocky material and carbon-rich grains, the latter nicknamed CHON particles after carbon, hydrogen, oxygen and nitrogen. This tied comets to the primitive dust also found in some meteorites.
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Level: Explorer Ages 10 and up