By Ed Bell and Phil Saunders

Like the terrestrial maps used by early navigators, maps of the other planets continue to become more and more detailed. The recent flybys of Mercury by NASA's MESSENGER spacecraft have added a new level of visual detail to the closest planet to the sun, allowing astronomers to better understand its origins and evolution. And a wealth of new data should be forthcoming soon; on March 17, MESSENGER is scheduled to become the first spacecraft to orbit Mercury.

The U.S. Geological Survey and the MESSENGER team have combined images from the 1973–75 Mariner 10 mission with images from MESSENGER's flybys to produce the first global mosaic map of Mercury. This map covers 97.7 percent of the planet's surface. You can view details of some of the more interesting and beautiful areas of this unique world in the following interactive feature.