The European Space Agency says that there are "not good signs" from a landing probe that was heading to the Martian surface, according to dpa. "Experts will work through the night to assess the situation" with the Schiaparelli probe, ESA said on its Twitter feed. Only around half of the over 40 missions to Mars since 1960 have been successful, with the planet's thin atmosphere making arrivals very difficult due to high velocity. The automated landing manoeuvre started 121 kilometres above the surface braking from a speed of 21,000 kilometres an hour. Mission Control at Darmstadt in Germany was unable to intervene due to the time delay.