A periodic comet discovered by the French astronomer Michel Giacobini (1873–1938) in 1900, and rediscovered two returns later, in 1913, by the German Ernst Zinner (1886–1970). Its orbital period is 6.6 years. Favourable and unfavourable apparitions alternate; at favourable returns, it may be as bright as 6th magnitude. Comet Giacobini–Zinner is the parent body of the Draconid meteor shower. In 1985 it became the first comet to be visited by a spacecraft, the International Cometary Explorer. Its orbit has a perihelion of 1.03 au, eccentricity 0.71, and inclination 31°.9.

http://cometography.com/pcomets/021p.html Information page at Cometography website.