Title graphic for Sea and Sky's astronomy reference guide, astronomers observing the night sky

Astronomy Software

This astronomy software page contains links to sites with PC software of interest to the astronomy hobbyist. These programs include useful astronomy utilities and programs that are educational and fun. Some of this software is free and some is commercial or shareware. There are also a few demo versions of some commercial software products.

Each entry contains a description of the software type as well as the last known price. Please read the information on each publisher's site for more detailed information. These astronomy software links are provided for informational purposes only. Sea and Sky does not endorse these products.

  • Astroviewer
    Platform: Windows 98 and above       Cost: Free      Demo: Download available
    AstroViewer is a planetarium software that helps you to find your way in the night sky quickly and easily. Due to its intuitive and easy-to-use graphical user interface, it fits well to the demands of astronomy beginners.

  • Celestia
    Platform: Windows, Linux, Mac OS X       Cost: Free      Demo: N/A
    Celestia is a very unique 3-dimensional universe simulator. With it you can travel throughout the Solar System, to any of over 100,000 stars, or even beyond the galaxy. Celestia comes with a large catalog of stars, planets, moons, asteroids, comets, and spacecraft. If that's not enough, you can download dozens of easy to install add-ons with more objects. The program is highly configurable and expandable. A library of add-ons and expansions is available including everything from additional stars & galaxies to science fiction worlds and spacecraft. For those with fast processors, you can even download and install super high resolution images of the planets and moons enabling you to zoom in close and explore every subtle detail. You can even take screen shots of your favorite scenes. Celestia is highly recommended by Sea and Sky!

  • Home Planet
    Platform: Windows 95 and above       Cost: Free      Demo: N/A
    Home Planet is a comprehensive astronomy, space, and satellite-tracking package for Microsoft Windows 95 and Windows NT 4.0 and above. Features include an Earth map showing day and night regions, position of selected satellites, positions of the planets, positions and phases of the Sun and Moon, sky map based on either the Yale Bright Star Catalogue or the 256,000 star SAO catalogue, including rendering of spectral types, planets, Earth satellites, asteroids and comets, and much more.

  • Stella 2000
    Platform: Windows 95 and above      Cost: Free      Demo: N/A
    Complete astronomy software suite exploring realistic skies in real time, with observing log, Sky Quiz, Live Orbits, telescope support, spoken pronunciation guide, a half-million word Encyclopedia Astronomica, and concentrated searches embracing planets, comets, asteroids, DSOs, and over 300,000 stars. An integral HTML guide to the solar system, a 1000-term astronomical dictionary, and the 2nd revised and enlarged edition of Aspects of Astronomy--a book-length primer covering topics such as "What are the Stars?", "Choosing a Telescope", "Cosmology", "Dark Matter", "Eclipses", and "The History of Astronomy", to name but a few--are closely coordinated with the sky display and picture windows.

  • Stellarium
    Platform: Windows, Linux, Mac OS X       Cost: Free      Demo: N/A
    Stellarium is a free GPL software program which renders realistic skies in real time with openGL. It is available for Linux/Unix, Windows and MacOSX. With Stellarium, you really see what you can see with your eyes, binoculars or a small telescope. Loaded with advanced features, this incredible software will turn your PC into a virtual planetarium! This is definitely one of the best free astronomy programs currently available for download. Stellarium is highly recommended by Sea and Sky!

  • WinOrbit
    Platform: Windows 3.1 or later       Cost: Free      Demo: N/A
    WinOrbit is a free software package for Microsoft Windows (3.1 or later), which will compute and display the position of artificial Earth satellites. The principal feature of WinOrbit is a series of Map Windows, which display the current position of satellites and observers on a simple world map, together with information such as bearing (azimuth), distance, and elevation above the observer's horizon. The maps can be updated in real time, or in simulated time, or manually set to show the situation at any time past or future. An additional Table Window displays much more-detailed information about one or more satellites in a tabular form.

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  • Cybersky
    Platform: Windows XP and above       Cost: $34.95      Demo: 30-day trial download available
    CyberSky is an exciting, entertaining, and educational astronomy program that transforms your personal computer into your personal planetarium. CyberSky provides an excellent way to learn about astronomy and to explore the wonders of the sky visible in the distant past, the present, and the far-off future. CyberSky displays accurate charts of the sky as seen from any location on the Earth. Sky charts can include stars, constellations, deep sky objects, and solar system objects, and can be enhanced by the addition of labels, coordinate system grids, and reference lines. CyberSky's user-friendly interface allows you to easily change your view of the sky, search for celestial objects, and display data about those objects. CyberSky also prints attractive sky charts that you can take outside with you.

  • StarStrider
    Platform: Windows XP and above       Cost: $22.00     Demo: 30-day trial download available
    StarStrider is a three-dimensional star plotting program that allows the user to see the stars and constellations from distant points in the sky. With the help of StarStrider you will be able to travel to the stars and watch their alien skies. Travel to Vega and see how the Sun pales to a faint star, a star among thousands of others. Look at the Pleiades from behind! With ordinary red/blue 3D glasses your experience will be even greater. Now you can see the variable distances to the stars - without even leaving our solar system if you don't want to! Cassiopeia looks really different when you realize that the constellation aren't flat. You'll also learn to appreciate the fact that the closest stars are not always the brightest.

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  • MegaStar Sky Atlas
    Platform: Windows 95 and above       Cost: $129.95      Demo: N/A
    MegaStar is the first software to integrate the Hubble Guide Star Catalog, and combine it with a massive deep sky database of 84,000 objects. It is also the first to implement the "eyepiece view," with deep sky objects plotted to scale and galaxies rotated to show position angle. This is an extremely detailed visual sky atlas program with too many features to mention here. Check out their site for more information. A demo version of the software is available for download.

  • Starry Night
    Platform: Windows XP & above, Mac OS X 10.4 & above       Cost: $24.95 - $239.95     Demo: N/A
    Starry Night is the most visually stunning and realistic astronomy program in its class. A powerful tool for both serious observers and casual stargazers, Starry Night lets you view the universe from anywhere in the Solar System. Explore over 19 million celestial objects and travel across 14,700 years of night skies. Features include a 19 million object Hubble Guide Star catalog and the ability to add new objects and databases. An evaluation version of the Basic version is available for download.

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