Finding Rosetta in the sky

Catching Rosetta's wake-up signal on 20 January 2014 using one of NASA's 70m stations was not without challenges.

Even after 31 months of no contact, however, the flight dynamics team at ESOC could predict the spacecraft's location in the sky to within just 2000 km at a distance of 807 million km – equivalent to a tiny fraction the size of a full Moon.