As expected, the European and Russian space agencies have delayed their next mission to Mars from 2018 to 2020. It is a decision that has been well telegraphed in recent months, with both officials and industry chiefs expressing their doubts that all the hardware could be made ready in time. The mission would see a rover landed on the Red Planet. Capable of drilling up to 2m below the surface, it would search for signs of past or present life. It is the second part of the so-called ExoMars programme. The first part - a satellite to study the atmosphere of the planet - was launched successfully in March and should arrive in October.