Jupiter probe's 'goodbye for now' to Planet Earth

This Earth (L) and the Moon (R) pictured by Juno on 26 August from a distance of 9.5 million km

The departing Juno probe has looked back and pictured Planet Earth.

Nasa's Jupiter-bound spacecraft imaged the pale blue dot at a distance of 9.5 million km during an early check-out of its camera and other onboard systems.

Juno was launched on 5 August and should arrive at the gas giant in 2016.

This is but a brief farewell. The probe must sweep back by Earth in 2013 for the "gravitational slingshot" that will give it the required speed to chase down Jupiter three years later.

The current plan is for Juno to spend a little over a year at the giant planet, orbiting over its poles.

It will use its remote sensing instruments to look down through Jupiter's atmosphere.

Scientists expect to learn more about its different layers and what precisely lies at the planet's core.

Juno will set a record for the most distant spacecraft powered by solar energy.

Out at Jupiter, the intensity of sunlight is only 1/25th of that at Earth. All previous probes to the gas giant have gone equipped with radioisotope batteries.

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