The 2014 Earth return of the ISEE-3/ICE spacecraft

In 1978, the 3rd International Sun–Earth Explorer (ISEE-3) became the first libration-point mission, about the Sun–Earth L1 point. Four years later, a complex series of lunar swingbys and small propulsive maneuvers ejected ISEE-3 from the Earth–Moon system, to fly by a comet (Giacobini–Zinner) for the first time in 1985, as the rechristened International Cometary Explorer (ICE). In its heliocentric orbit, ISEE-3/ICE slowly drifted around the Sun to return to the Earth׳s vicinity in 2014. Maneuvers in 1986 targeted a 2014 August 10th lunar swingby to recapture ISEE-3 into Earth orbit. In 1999, ISEE-3/ICE passed behind the Sun; after that, tracking of the spacecraft ceased and its control center at Goddard was shut down. In 2013, meetings were held to assess the viability of “re-awakening” ISEE-3. The goal was to target the 2014 lunar swingby, to recapture the spacecraft back into a halo-like Sun–Earth L1 orbit. However, special hardware for communicating with the spacecraft via NASA׳s Deep Space Network stations was discarded after 1999, and NASA had no funds to reconstruct the lost equipment.