The National Aeronautic and Space Administration's (NASA) sagging planetary exploration effort may get some relief through participation in other nation's space missions. The only planetary mission approved by Congress and underway at this time is the Galileo Jupiter orbiter and probe, and that has been affected by delays in the space shuttle.
NASA planners have discussed, with European and Japanese investigators, three missions of importance to planetary researchers. The European Space Agency's (ESA) ‘Giotto’ mission would pick up the probe portion of NASA's ill-fated Halley/Tempel II rendezvous and flyby. ESA was originally scheduled to prepare an instrumented probe that would be aimed at the nucleus of Halley's comet from a main spacecraft that would have flown past Halley's, then rendezvoused with Tempel II and flown along with it.