This spectacular color mosaic shows the eastern limb of Mercury as seen by MESSENGER as the spacecraft departed the planet following the mission's first Mercury flyby in January 2008. The colors of this image are not those that would be seen by the human eye but instead convey information about the distribution of different rock types on Mercury's surface. The different rock types result in subtle color variations across all of the 11 WAC narrow-band color filters. The Caloris basin, visible as a large bright yellow circular area in this image due to its infill of volcanic plains, dominates the northern region. A similar image was published in Science magazine in July 2008, but it only covered the northern half of the region shown here. To create this larger color mosaic, MESSENGER Science Team members had to also devise a method to deal with scattered light in the 11 different WAC filters. MESSENGER has obtained color imaging at this resolution only for the portions of Mercury seen on departure from Mercury flybys 1 and 2.

As spectacular as this color image is, it is just a taste of what is yet to come. In 2011, MESSENGER will become the first spacecraft ever to orbit Mercury and begin a year-long observing campaign that includes imaging all of Mercury's surface in color at an average resolution of about 1 kilometer/pixel (0.6 miles/pixel), a resolution that is about a factor of three better than this already impressive image.

Date Acquired: January 14, 2008
Instrument: Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS)
Resolution: 2.8 kilometers/pixel (1.7 miles/pixel) at the equator
Scale: Caloris basin is about 1,550 kilometers (960 miles) in diameter
Spacecraft Altitude: 13,000 kilometers (8,000 miles)

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.