One scientist involved in the mission suspects human error. At present an unnoticed navigation error seems the most likely cause of the loss. Tracking data from the spacecraft suggests there were indications that it was on the wrong course in the hours before it was lost. Cutbacks Political reaction to the failure has bemused many American scientists. They say they cannot understand supportive statements from Washington about the loss - just as the US Government plans dramatic cuts in Nasa's space science budget.
Missions are smaller and more numerous.
The theory is that just as much science can be carried out without the risk of putting all hopes into one large spaceprobe. The next mission to Mars, the Mars Polar Lander, will touch down in December. Following that, Nasa plans to launch Mars missions every two years from 2001 to 2009. Despite this setback, the exploration of Mars is really just beginning. The BBC is not responsible for the content of external internet sites.