The British-led Beagle 2 probe was the lander for the Mars Express  mission. It was released on 19 December 2003, but nothing was heard from it after its scheduled touchdown. (It was subsequently located on Mars in 2014, demonstrating its successful landing.)

The mission played a key role in the international exploration programme for Mars, focusing on global coverage and the search for water and life, with the orbiter’s instruments providing remote sensing of the atmosphere, ground and up to 5 km below the surface.