Any doctor will tell you that one of the best sources of information on a sick patient is the patient himself. That's certainly true for NASA's ailing Mars rover Spirit. Just before noon on Friday, the rover, which has been in "safe" mode since Wednesday, sent to the orbiting Mars Odyssey probe a surprise burst of information, including data on its power subsystem. That's heady stuff for engineers at the Jet Propulsion Lab in Pasadena (CA). The rover sent 73 megabits of information in all. The transmission was interesting, since JPL sent Spirit a command to "sleep," which it seems as if Spirit totally ignored. JPL has said Spirit's flight software just isn't working right, in spite of commands to reboot the probe's system at least 60 times.

As American scientists struggle to contact their Spirit rover and Europeans have virtually given up hope of finding their Mars lander, Beagle 2, the EU orbiter Mars Express has confirmed what was long suspected about the Red Planet: There was once an abundance of water. "I think we can firmly say 'yes, there was water acting on the surface of Mars," said European Space Agency scientist Gerhard Neukum.