The Mars Express spacecraft, carrying the Beagle 2 lander, was launched on 2 June last year, arriving in the vicinity of Mars in December. The separation of Beagle 2 from Mars Express occurred on 19 December. The satellite continued its mission with its successful insertion into a Mars orbit on 25 December, the day on which Beagle 2 was due to land.
The first radio contact with Beagle 2 was expected shortly after the scheduled landing time but no signal was received. Many radio contacts were attempted over the following days and weeks, but without result. By early February it became clear that there was no prospect of communicating with Beagle 2 and a joint ESA/UK inquiry was set up to investigate the circumstances and possible reasons that prevented completion of the Beagle 2 mission.
More at:
http://www.esa.int/esaCP/SEMLKAHHZTD_index_0.html