ICE/ISEE-3 update: Amateurs detect its signal while professionals study contacting it, Planetary Society
“Since the last time I reported on ICE/ISEE-3, there have been several developments. As a reminder, ISEE-3 was launched in 1978 to study Earth’s magnetosphere and repurposed in 1983 to study two comets. Renamed the International Cometary Explorer (ICE), it has been in a heliocentric orbit since then, traveling just slightly faster than Earth. It’s finally catching up to us from behind, and will return to Earth in August. It’s still functioning, broadcasting a carrier signal that the Deep Space Network successfully detected in 2008. If we command the spacecraft to fire its engines at the appropriate moment — something that must happen within the next few months — we can recapture it into a halo orbit at the Sun-Earth L1 Lagrangian point.”