I've periodically reported on the status of the International Sun-Earth Explorer (ISEE-3), a spacecraft that 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. Twelve of its 13 instruments were working when we last checked on its condition, sometime prior to 1999.The funny thing is that ICE/ISEE-3 shouldn't even be broadcasting a signal. It was supposed to be shut down. So the equipment needed to understand it and send it orders was decommissioned in 1999. Fifteen years later, the cost to reequip the Deep Space Network is prohibitive. As opposed to keeping in touch with Voyager 1 and 2 as they head into interstellar space -- we expected to be able to communicate with them even at over fourteen billion miles.
It's a shame, really, because there'd otherwise be the possibility of getting even more out of this mission. Added value. Dang we've built some good equipment. Some of this stuff works longer than we care or can afford to use. And I'm thrilled to have an 18-year-old Blazer running well with 309,000 miles.
Space travel is hard. Some missions go awry and never work. Some rovers go on forever, like Curiousity, others freeze up like Jade Rabbit. It's a high stakes crap shoot and one we take too lightly at times.
One wonders whether Randall Monroe of xkcd will immortalize this moment in human exploration history as he did with the Mars rover Spirit. Or if this abandonment will be one more reason for Skynet to hate us come the Singularity. (grin)
UPDATE 3/3/2014: He did! (grin) http://imgs.xkcd.com/comics/hack.png I am happy now.