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Google Earth Only few know that the Google Earth application was first originated as EarthViewer 3D and wasn't, in fact, developed by Google. At the time of its first release, it belonged to Keyhole, and only later, in 2004, it was acquired by Google.
Since then it was enriched with fresh data, images and new impressive features for the users.
At the moment, there are three versions of the application: one for PC, a web-based one, and one for Android/iOS-devices. The PC version is available in different flavors: Google Earth (free), Google Earth Pro (for about $400) and Google Earth Enterprize.
First of all, the free version of this program allows you to travel around the globe visiting any country you wish and either view some photographs of memorable places alongside the information about them, or travel around the streets of a city via the Street View mode. The only drawback of the latter is that it is available for a limited number of cities. Still, if you want to have a tour around Paris or Berlin there won't be any difficulties. Besides, if the Street View is available for the city you are traveling to, you can use it like a 3D map to find your way around the city, or as a trip planner, making a video tour beforehand and following it later. Also, you can use this application to teach your kids the day-night change, providing visualization of the process, or to study together how the world looked some decades ago, using historical imagery.
Apart from our planet, you can travel around the space or visit other celestial bodies like Mars or the Moon. You can rotate and zoom them, view photos, read facts and trivia about them. There are lots of new things to learn about sitting in front of your monitor: the Moon, for example, features marks of expeditions and notable geographic places, like craters or hills.
Unfortunately, if you want to experience the full beauty and speed the application is capable of, you need a very powerful computer. If you do have one, you will get an unforgettable experience traveling on the three planets, or just around the space.
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Stellarium Stellarium a free program that puts a 3D planetarium on your computer screen.
It lets you choose your viewing point coordinates, so you can watch the sky on the screen as if you were using a telescope in real life.
You can make the illusion more realistic adding atmosphere effects and views including the ground.
You can point to a star using your mouse, and the program will show you the information about that star, like Name, Distance, Magnitude and Position in the sky.
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Celestia Celestia is a really nice tool that lets you explore the Universe as it provides real-time 3D visualization of space. Celestia is impressively comprehensive as it is based on the Hipparcos Catalogue (the result of the European Space Agency's "astrometric" mission from November 1989 to March 1993) and therefore contains more than 100,000 stars.
Even though it already contains a detailed model of the solar system and can be used to additionally explore tens of thousands of other galaxies, the tool still provides the possibility of adding more objects to its library (mainly by downloading add-ons).
Another great thing about Celestia is the exponential zoom feature. It makes traveling around the space very fast and smooth. Passing from a faraway galaxy cluster to the close by Moon or Mars will be done in an instant. This makes Celestia really enjoyable to use, especially since it also comes with handy exploration features like a star browser, a solar system browser, and a tour guide. Its navigation menu allows quickly jumping to a solar object regardless of its type and location.
Though feature-rich and comprehensive, Celestia is not hard to use. Its interface is simple, straightforward and intuitive, allowing even complete beginners to handle it with ease.
Simply put, Celestia is a great tool, both educational and entertaining. The fact that it’s also open source makes it even more appealing. I enjoyed using it and recommend it with all my heart.
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WorldWide Telescope WorldWide Telescope is a great application. It is a virtual telescope. You could see almost all the known stars, galaxies, nebulae and planets. It is really cool to zoom through the sky, if you are interested in astronomy.
This will be a great application for schools, especially when you consider that it is a freeware. One main problem is that it needs a powerful graphics card to fully utilize its graphical capabilities. This is a Web 2.0 application. This program is like "Celestia", which is actually open source. But WorldWide Telescope has a lot of other capabilities.
The images are mainly taken from the Hubble Space Telescope. You can zoom in to any star you like and the images get better as they are downloaded automatically.
What I really liked was the guided tours. There are a lot of guided tours which are created by this application. It shows you around the world with audio describing different starts, galaxies, black holes, etc. As the program has the capability of going back or forth in time, it is really easy to create such guided tours.
Even if it needs a broadband connection for a proper working, the data to be downloaded is small. The guided tours are not much big in size. But if your internet connection is slow, you will miss a lot of detail like the pictures about which is being spoken (as it cannot stop the audio to wait for the image to be downloaded).
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