International Cometary Explorer (ICE)

The International Cometary Explorer (ICE) spacecraft (designed and launched as the International Sun-Earth Explorer-3 (ISEE-3) satellite), was launched August 12, 1978, into a heliocentric orbit. It was one of three spacecraft, along with the mother/daughter pair of ISEE-1 and ISEE-2, built for the International Sun-Earth Explorer (ISEE) program, a joint effort by NASA and ESRO/ESA to study the interaction between the Earth’s magnetic field and the solar wind. ISEE-3 was the first spacecraft to be placed in a halo orbit at the L1 Earth-Sun Lagrangian point. Renamed ICE, it became the first spacecraft to visit a comet, passing through the plasma tail of comet Giacobini-Zinner within about 7,800 km (4,800 mi) of the nucleus on September 11, 1985.