Xplanet is described as 'is free software, distributed according to the terms of the GNU General Public License' and is an app in the Travel & Location category. There are more than 10 alternatives to Xplanet for a variety of platforms, including Windows, Mac, Android, iPhone and Android Tablet. The best alternative is TerraTime. It's not free, so if you're looking for a free alternative, you could try Desktop Earth or MeteoEarth. Other great apps like Xplanet are EarthDesk (Paid), EarthView (Paid), Living Earth (Paid) and Earth 3D (Paid).
TerraTime provides an amazing, interactive, real-time virtual Earth. Its globes and maps use current satellite imagery to simulate day/night, clouds, seasons, sun & moon; clock shows rise, set, twilight, & transit times for sun & moon.
You should run it as admin. Desktop Earth is a wallpaper generator. It will generate a high-resolution, accurate representation of the Earth. The imagery is based on NASA's Blue Marble Next and Earth's City Lights.
xplanet (by Hari Nair) is a great piece of software capable of creating renderings inside our solar system. To raise the quality of its output adding some graphical effects, it was a great candidate to link with imagemagick.