Are we any closer to learning about the origins of our universe after the historic landing in November of a European robot probe on a comet? The mission began 21 years ago, and the probe Rosetta travelled nearly six and a half billion kilometres to reach the comet. The scenes of cheering and hugs amongst the expert team at the European Space Agency in Germany reflected the deep joy and sense of accomplishment. Hardtalk speaks to professor Monica Grady, a member of the Probe's scientific team. Now the euphoria has subsided - what did we learn from this historic landing?