Taking advantage of extra solar energy collected during the day, NASA's
Mars Exploration Rover Spirit settled in for an evening of stargazing,
photographing the two moons of Mars as they crossed the night sky. The
first two images in this sequence show gradual enhancements in the surface
detail of Mars' largest moon, Phobos, made possible through a combination
technique known as "stacking." In "stacking," scientists use a
mathematical process known as Laplacian sharpening to reinforce features
that appear consistently in repetitive images and minimize features that
show up only intermittently. In this view of Phobos, the large crater
named Stickney is just out of sight on the moon's upper right limb.
Spirit acquired the first two images with the panoramic camera on the
night of sol 585 (Aug. 26,2005). The far right image of Phobos, for
comparison, was taken by the High Resolution Stereo Camera on Mars
Express, a European Space Agency orbiter. The third image in this sequence
was derived from the far right image by making it blurrier for comparison
with the panoramic camera images to the left. More information about the
Mars Express image is available at http://www.esa.int/SPECIALS/Mars_Express/SEM21TVJD1E_1.html"
Scientists will use images of the two moons to better map their orbital
positions, learn more about their composition, and monitor the presence
of nighttime clouds or haze.
