The comet-chasing spacecraft, Rosetta, has woken from nearly three years of hibernation to complete its deep space mission that scientists hope will help unlock some secrets of the solar system.
A computer-generated image shows Rosetta, the billion-dollar comet-chasing spacecraft. Photo: AFP / CNES-ESA
"Hello, world!" the European Space Agency said on Twitter on Monday, mimicking the signal sent back from deep space by the billion-dollar unmanned craft.
The agency described Rosetta as a "sleeping beauty" that had emerged from a long sleep.
"It was a fairy-tale ending to a tense chapter," it said.
Rosetta was launched by the European Space Agency in 2004 and is due to rendezvous with comet 67P/Churyumov-Gerasimenko later this year and land a probe on it, in an unprecedented manoeuvre.
The comet, a roughly three by five kilometre-large rock, was discovered in 1969.
Scientists hope data gathered will provide clues about what the world looked like when the solar system was born.
