3D World Map is a powerful and high-definition three-dimensional world map (Note that: it is a 'Map' rather than 'Earth'). It enables you to accurately find 269 countries and regions in the world on this realistic tellurion, and precisely displays the locations of more than 30000 cities around the world. Plus, it can calculate the distance between any two points on the earth, and all mountains, rivers, lakes and seas can be seen with a glance on this 3D tellurion.
Universe Sandbox is a very cool software designed to simulate the physical interaction movements (you can create & destroy on an unimaginable scale) of universe stars perfectly. It has a 3D engine with very high simulation degree, and is a pretty darned good simulator (also can be regarded as a scientific game) for understanding the whole universe.