Juno hits a snag, but Jupiter is still in sight

PUBLISHED : Friday, 11 October, 2013, 12:00am
UPDATED : Friday, 11 October, 2013, 3:34am


Nasa's Jupiter-bound spacecraft hit a snag soon after it used earth as a gravity slingshot to hurtle towards the outer solar system, but mission managers said it is still 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 is some trouble.

Despite the problem, "we believe we are on track as planned to Jupiter", said Rick Nybakken, of the Nasa Jet Propulsion Laboratory, which manages the US$1.1 billion mission.

Before whipping around earth in a momentum-gathering flyby, Juno had been in excellent health until Wednesday. It can communicate with ground controllers in safe mode, 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.

Launched in 2011, Juno flew beyond the orbit of Mars, earth's closest planetary neighbour, before looping back. That boosted Juno's speed from 125,500 km/h relative to the sun to 140,000 km/h - enough to cruise past the asteroid belt to Jupiter.