The High Resolution Imaging Science Experiment (HiRISE) camera on NASA’s Mars Reconnaissance Orbiter recorded a scene on Jan. 29, 2012, that includes the first color image from orbit showing the three-petal lander of NASA’s Mars Exploration Rover Spirit mission. Spirit drove off that lander platform in January 2004 and spent most of its six-year working life in a range of hills about two miles to the east.
Another recent image from HiRISE, taken on Jan. 26, 2012, shows NASA’s Phoenix Mars Lander and its surroundings on far-northern Mars after that spacecraft’s second Martian arctic winter. Phoenix exceeded its planned mission life in 2008, ending its work as solar energy waned during approach of its first Mars winter.
The image showing Spirit’s lander platform as a small, bright feature southwest of Bonneville Crater is athttp://photojournal.jpl.nasa.gov/catalog/PIA15038. The new image of Phoenix is athttp://photojournal.jpl.nasa.gov/catalog/PIA15039 .
Ever since the NASA Viking mission, which reached Mars in 1976, there has been considerable interest in the composition of Martian soils. Some Viking measurements indirectly suggested that the soils contained highly oxidizing compounds, which could present extremely harsh conditions for life. Recent observations from the Phoenix Mars Mission pointed to evidence of perchlorate, a potentially highly oxidizing compound, in the Martian soils. However, some studies have noted that because perchlorate is highly stable, its presence in Martian soils cannot explain the Viking measurements. Quinn et al. (2011) present a new analysis of Mars soil samples using the Wet Chemistry Laboratory, a component of the Microscopy, Electrochemistry, and Conductivity Analyzer on the NASA Mars Phoenix Lander. They found that although low levels of oxidizing compounds may be present, the oxidation-reduction potential of the soil is moderate and well within the range expected for habitable soils.