xplanet is similar to xearth, where an image of the earth is rendered into the X root window. Various projection systems are available for display. The user can also popup a window with a globe that can be rotated interactively.
xplanet is already packaged in the main Debian archive.
Xplanet homepage http://xplanet.sourceforge.net
French presentation: http://www.tice.ac-versailles.fr/logicielslibres/spip.php?article43