11 September
1985: On 11 September 1985, the International Cometary Explorer (ICE) made the first encounter with a comet tail - a fly-by of Comet P/Giacobini-Zinner.
The spacecraft, launched in 1978 by NASA, had been called the International Sun-Earth Explorer 3 (ISEE-3) as its original mission had been to study the interaction between Earth and the Sun. ISEE-3 was renamed the International Cometary Explorer when, after completing its original mission in 1982, it was manoeuvred to intercept Comet P/Giacobini-Zinner.
ESA's Giotto mission intercepted Comet Halley in 1986.