NASA's Jupiter-bound spacecraft hit a snag soon after it used Earth as a gravity slingshot to hurtle toward the outer solar system, but mission managers said it's on course to arrive at the giant planet in 2016.
Juno emerged from Earth's shadow in safe mode, a state that spacecraft are programmed to go into when there's some trouble.
Despite the problem, "we believe we are on track as planned to Jupiter," said project manager Rick Nybakken of the NASA Jet Propulsion Laboratory, which manages the US$1.1 billion mission.
Engineers continued to diagnose the issue, which occurred after Juno whipped around Earth in a momentum-gathering flyby. Up until Wednesday, Juno had been in excellent health. While in safe mode, it can communicate with ground controllers, but its activities are limited.
Previous missions to the outer solar system have used Earth as a celestial springboard since there's no rocket powerful enough to make a direct flight. The Galileo spacecraft buzzed by Earth twice in the 1990s en route to Jupiter, the solar system's largest planet located 484 million miles from the sun.