Life on Mars If the surface life has been reanimated as recently as 450,000 years ago, then rovers on Mars could find dormant but still viable life at a depth of one meter below the surface, according to an estimate. In 1965, the Mariner 4 probe discovered that Mars had no global magnetic field that would protect the planet from potentially life-threatening cosmic radiation and solar radiation; observations made in the late 1990s by the Mars Global Surveyor confirmed this discovery. Scientists speculate that the lack of magnetic shielding helped the solar wind blow away much of Mars's atmosphere over the course of
Cydonia (region of Mars) two computer engineers at NASA's Goddard Space Flight Center. DiPietro and Molenaar discovered the two misfiled images, Viking frames 035A72 and 070A13, while searching through NASA archives. More than 20 years after the "Viking 1" images were taken, a succession of spacecraft visited Mars and made new observations of the Cydonia region. These spacecraft have included NASA's Mars Global Surveyor (1997–2006) and Mars Reconnaissance Orbiter (2006–), and the European Space Agency's "Mars Express" probe (2003–). In contrast to the relatively low resolution of the Viking images of Cydonia, these new platforms afford much improved resolution. For instance, the "Mars Express"