As the MESSENGER team continues to study the high-resolution images taken
during the Mercury flyby encounter on January 14, 2008, scarps (cliffs)
that extend for long distances are discovered. This frame, taken by the
Narrow Angle Camera (NAC) of the Mercury Dual Imaging System (MDIS), shows
a region of Mercury's surface previously unseen by spacecraft and a large
scarp crossing vertically through the scene, on the far right of the
image. This scarp is the northern continuation of the one seen in the NAC
image released on January 16 (PIA10174). The width of this image is
about 200 kilometers (about 125 miles), showing that these scarps can be
hundreds of kilometers long on Mercury.
The presence of many long and high scarps, as discovered from pictures
from the Mariner 10 mission in 1974 and 1975, suggests a history for
Mercury that is unlike that of any of the other planets in the solar
system. These giant scarps are believed to have formed when Mercury's
interior cooled and the entire planet shrank slightly as a result.
However, Mariner 10 was able to view less than half the planet, so the
global extent of these scarps has been unknown. MESSENGER images, like
this one, are providing the first high-resolution looks at many areas on
Mercury's surface, and science team members are busy mapping these newly
discovered scarps to see whether they are common everywhere on the planet.
Mission Elapsed Time (MET) of image: 108826206
These images are from MESSENGER, a NASA Discovery mission to conduct the
first orbital study of the innermost planet, Mercury. For information
regarding the use of images, see the MESSENGER image use policy.
