Lander (spacecraft) a landing which should have come on 25 December 2003 was not received. Indeed, no communication was ever established and "Beagle 2" was declared lost on 6 February 2004. The proposed 2009 British Beagle 3 lander mission to search for life, past or present was not adopted. The French/ESA NetLander mission for 2007 or 2009, with an orbiter and 4 landers, was cancelled because it was too expensive. Its successor, Mars MetNet, a multi-lander mission for 2011–2019 was not adopted by the ESA. The American Mars Exploration Rovers "Spirit" and "Opportunity" were launched in June and July 2003. They reached
The Mars Project are other shortcomings in "The Mars Project" that von Braun could not have anticipated in 1948. He had not planned on any unmanned exploratory missions to Mars taking place before the first manned expedition, and he had not foreseen the technological advances that would take place, or the development of robot spacecraft. It was not until 1965 that the unmanned Mariner 4 spacecraft found that the density of the Martian atmosphere was only one tenth of what had been estimated, making it clear that the huge winged gliders planned by von Braun would not have had enough lift to be