Rosetta comet landing: Professor's excitement and tears

"It's landed - I've waited years for this", Professor Monica Grady has said, on finding out that the robot probe Philae had landed on a comet.

The landing caps a 6.4 billion-kilometre journey that was begun a decade ago.

Prof Grady of the Open University worked on a tool of the project called Ptolemy - a shoe-box-sized gas analysis instrument.

She was in on the Philae lander project from its earliest days and jumped for joy when she found out the news, even hugging the BBC's Science Editor David Shukman.