A Swiftly Non-Tilting Planet

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Caption:

This image was taken with the Wide Angle Camera (WAC) and shows part of Mercury's southern hemisphere, taken from the far south, looking north. (The companion image, showing the rest of the southern hemisphere, can be found here .) Unlike Earth (referred to in the title of Madeleine L'Engle's book A Swiftly Tilting Planet ), Mercury has a very small axial tilt of only about .02 degrees--the smallest in the Solar System. As a result, Mercury has no seasons.

This image was acquired as part of MDIS's limb imaging campaign. Once per week, MDIS captures images of Mercury's limb, with an emphasis on imaging the southern hemisphere limb. These limb images provide information about Mercury's shape and complement measurements of topography made by the Mercury Laser Altimeter (MLA) of Mercury's northern hemisphere.

Date acquired: May 24, 2011
Image Mission Elapsed Time (MET): 214697100
Image ID: 290398
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
WAC filter: 7 (748 nanometers)
Center Latitude: -58.74°
Center Longitude: 273.9° E
Resolution: 2836 meters/pixel
Scale: Mercury's diameter is 4880 km (3032 miles)

Background Info:

The MESSENGER spacecraft is the first ever to orbit the planet Mercury, and the spacecraft's seven scientific instruments and radio science investigation are unraveling the history and evolution of the Solar System's innermost planet. Visit the Why Mercury? section of this website to learn more about the key science questions that the MESSENGER mission is addressing.

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 .

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