Recycling an existing spacecraft that has already completed its original mission makes good sense for a number of reasons. The spacecraft has already been designed, built, and launched in the course of its original mission. These are typically the most expensive parts of any mission. For the price of a little on-board propellant needed to nudge a craft on a new trajectory and a modest amount of additional funding for mission operations and science, an existing spacecraft can sometimes be sent to another target of interest.
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On September 18, 2008, ICE, which had finally begun drifting closer to the Earth, was located and successfully reactivated. It was found that all but one of its 13 instruments were still functioning and enough propellant remained on board for a velocity change of 150 meters per second (320 miles per hour). There appeared to be enough life left in the old probe to perform more useful science. ICE should return to the Earth-Moon system again around August 10, 2014—over three decades after it left. NASA scientists, including a team lead by Robert Farquhar, are considering several options for the future of ICE, including redirecting it towards additional comet encounters in 2017 or 2018. Still other missions are possible for this robust, reused spacecraft before it once again drifts back into interplanetary space and subsequently returns to the vicinity of the Earth sometime in the 2040s.
Recycling an existing spacecraft that has already completed its original mission makes good sense for a number of reasons. The spacecraft has already been designed, built, and launched in the course of its original mission. These are typically the most expensive parts of any mission. For the price of a little on-board propellant needed to nudge a craft on a new trajectory and a modest amount of additional funding for mission operations and science, an existing spacecraft can sometimes be sent to another target of interest. ... On September 18, 2008, ICE, which had finally begun drifting closer to the Earth, was located and successfully reactivated. It was found that all but one of its 13 instruments were still functioning and enough propellant remained on board for a velocity change of 150 meters per second (320 miles per hour). There appeared to be enough life left in the old probe to perform more useful science. ICE should return to the Earth-Moon system again around August 10, 2014—over three decades after it left. NASA scientists, including a team lead by Robert Farquhar, are considering several options for the future of ICE, including redirecting it towards additional comet encounters in 2017 or 2018. Still other missions are possible for this robust, reused spacecraft before it once again drifts back into interplanetary space and subsequently returns to the vicinity of the Earth sometime in the 2040s.