Google Earth lets you fly anywhere on Earth to view satellite imagery, maps, terrain, 3D buildings, from galaxies in outer space to the canyons of the ocean. You can explore rich geographical content, save your toured places, and share with others.
Stellarium is a free open source planetarium for your computer. It shows a realistic sky in 3D, just like what you see with the naked eye, binoculars or a telescope.
Stellarium vs Planetarium opinions
It's downloadable on Linux, so it can be used offline.
Celestia is an application for real-time 3D visualization of space, with a detailed model of the solar system, over 100,000 stars, more than 10,000 galaxies, and an extension mechanism for adding more objects.
World Wind lets you zoom from satellite altitude into any place on Earth. Leveraging Landsat satellite imagery and Shuttle Radar Topography Mission data, World Wind lets you experience Earth terrain in visually rich 3D, just as if you were really there.
Gaia Sky is a real-time, 3D, astronomy visualisation software that runs on Windows, Linux and OS X. It is developed in the framework of ESA's Gaia mission to chart about 1 billion stars of our Galaxy in the Gaia group of the Astronomisches Rechen-Institut (ZAH...
KStars is a Desktop Planetarium for KDE. It provides an accurate graphical simulation of the night sky, from any location on Earth, at any date and time. The display includes upto 100 million stars, 13,000 deep-sky objects,all 8 planets, the Sun and Moon, and thousands of comets...This app doesn't have any features at the moment.
SkyView is powerful, easy-to-use app that answers questions about stars, constellations, and more. Simply point the camera to the sky, tap on what you see and discover neat things about these sky objects.
Indispensable for amateurs and professionals, as well as for kids who are eager to learn, Star Walk will guide you through the night sky in style.