A space odyssey nears an end

Once upon a time, two intrepid space adventurers called Rosetta and Philae set out from Earth to explore a comet far, far away.

So begins the fairy tale adventure of Europe's comet chaser and robot probe, steel boxes with charming cartoon counterparts and a global following of fans fated for heartbreak when the pair severs ties with Earth forever.

"I think there will be a lot of tears," said European Space Agency senior science adviser Mark McCaughrean ahead of D-Day on Sept 30.