Celestiaby SchoolForge updated November 23, 2011
The free space simulation that lets you explore our universe in three dimensions.

Software Details

The free space simulation that lets you explore our universe in three dimensions.

Unlike most planetarium software, Celestia doesn't confine you to the surface of the Earth. You can travel throughout the solar system, to any of over 100,000 stars, or even beyond the galaxy.
All movement in Celestia is seamless; the exponential zoom feature lets you explore space across a huge range of scales, from galaxy clusters down to spacecraft only a few meters across. A 'point-and-goto' interface makes it simple to navigate through the universe to the object you want to visit.
Celestia is expandable. Celestia comes with a large catalog of stars, galaxies, planets, moons, asteroids, comets, and spacecraft. If that's not enough, you can download dozens of easy to install add-ons with more objects.


Operating systems: Windows, Linux, BSD, Mac OSX
Screen libraries: Gnome, KDE or Glut

  • Windows
    • The Windows package of Celestia is a self-extracting archive; download it to your computer and then run it.
  • Mac OS X
    • The Mac OS X package is a disk image. Download it to your computer, double click it, and follow the instructions in the README.
  • Linux (x86)
    • If you are running Linux, you should check first with your distribution; there is a good chance that the package is available to you in the format best suited to your installation. A pre-compiled 32-bit version is provided in the autopackage format. It should run on any distribution that has OpenGL and GTK+ 2.6.


Average: 4 (1 vote)

Celestia is a program designed to accompany the study of the sky. As a teacher of college courses in astronomy, mostly online but occasionally live, this program had immediate value to me. The program's focus is the solar system; this is evident from the guided tour found in the drop-down menu. The images of the planets, moons, asteroids, and comets are the most current available. Some images look realistic, but, given that they are of the small asteroidal satellites of Jupiter and Saturn, may just be good artistic renditions. I found the greatest value to be not the images but the orbital mechanics that can be so faithfully rendered. Kepler's Laws are easily demonstrated by displaying the orbits, locking onto one body (planet or moon), and adjusting the time rate. The lock phase feature helps with understanding retrograde motion. Beyond the solar system, there are the stars and the galaxies which are mainly background. I found little value there for my instruction beyond some relative sizes and the concept of galaxies as a whole. Overall, 4.5 stars!!!

I am reviewing this software
Average: 5 (1 vote)

I am reviewing this software as an elementary teacher looking for software that I can use in the classroom. Celestia is a 3-D space simulation software that allows you to move through and learn about space. You can explore and just click around, or you can use the “goto” function to type in different places you want to go. When you go to a planet you'll see the distance, radius, apparent diameter, and phase angle. You can also click on Info, which will take you to a website that gives you a ton of information about the planet. Students are also able to view the orbit of Earth. This software is very easy to install and use.

-graphics make it very engaging for students
-easy to install
-relatively easy to navigate
-able to view orbit in real time, 10x slower, or 10x faster

-might take a little exploring to get used to navigating the software
-to get more information about the planet you are taken to a different website

I think this would be a really great way for elementary students to learn and explore space. One of the science concepts is that students will explain how day and night are caused by the rotation of the Earth, and I think this would be an excellent model to show students this rather than just explaining. There are also a ton of addons that you can download and install from here http://www.celestiamotherlode.net/catalog/solarsystem.php.