NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif., was riding high last summer following its latest dazzling success: the successful landing of the car-sized Curiosity Mars rover on the red planet. But the next big thing for the laboratory, NASA's traditional go-to center for the most challenging planetary missions that breach humanity's frontiers, is essentially a repeat performance, now scheduled to launch in 2020. Budget pressures have forced NASA to shelve more-ambitious efforts to cache martian samples for eventual return to Earth and to orbit Europa, the jovian moon that has intrigued scientists and dreamers for decades.
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