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Mars MOLA Viewer

Example View: Valles Marineris

The Mars Orbiter Laser Alitimeter experiment carried on the Mars Global Surveyor spacecraft produced a topographic map of the entire surface of Mars. The data for this map is available on the Internet. The Mars MOLA Viewer will download this data for you and render it as a 3-D landscape which you can "fly" through in real-time. Read the help page for more information.


Broadband internet access isn't required but it is strongly encouraged. The program downloads the topographic data files from the official MOLA site on the internet; there are 16 of these files, about 128 MB each, totaling 2 GB. If you don't have broadband each of these files could take 10 hours or more to download. You don't need all the files to view terrain; if you are going to download only some of the files I recommend the area around the Valles Marineris for interesting terrain. The program itself is about 2 MB; if you also need to install Java (see below) there is an additional 10 MB download.

Mars MOLA Viewer has been tested and should run with Windows 2000, Windows XP, and Linux x86/Linux x86_64 PC's (if you are interested in helping with a port to other platforms that support Java and OpenGL, contact me.) It may well run with Windows ME or Windows 98 if you have correct OpenGL drivers. In order to get acceptable performance, you will need at least 256 MB of memory as well as a >1 GHz CPU and/or a video chip that provides transform and lighting acceleration, such as an ATI Radeon or NVidia GeForce. You'll also need working OpenGL drivers for your video chip. Most PCs sold since 2002 will do fine.

The Java 1.4+ runtime with Java Web Start is also required. If you run Mars MOLA Viewer from the launch link below these should automatically download if you don't have them. If this automatic install doesn't work (you'll get a message like "File of type application/x-java-jnlp, save to disk or choose an application to run") use this link to download and install Java Web Start for your platform.


Mars MOLA Viewer may have bugs, including bugs that may crash your computer. It is offered free of charge in the hopes that it will be entertaining but with ABSOLUTELY NO WARRANTY.

Known Bugs

When run with Blackdown Java Java Web Start on AMD64 architectures, the OpenGL lighting seems to be off.  If you are running into this problem, drop me a line.

Running the Program

Mars MOLA Viewer runs right from your browser. Use the launch link below.

If you have the Java runtime installed and your browser still can't start the application, check here for help configuring your browser or for instructions on launching Mars MOLA Viewer from the command line. If Java Web Start starts but gives an error message, see the troubleshooting guide.

A Note on Security

There are always risks in downloading executable content from the web. Java Web Start seeks to minimize these risks by running downloaded code in a "sandbox" where it is prevented from fully accessing your computer, or by requiring that the code be signed with a public key certificate. Mars MOLA Viewer has to run outside the "sandbox" in order to access its native code OpenGL graphics libraries. It is therefore signed with a certificate. You will have to accept this certificate before Java Web Start will run the program.

Code signed with a certificate is more secure than unsigned code, because you can be confident that the code you downloaded is the same code that the holder of the certificate signed. Still, accepting the certificate implies that you trust the owner of the certificate not to include malicious code with the program you downloaded.

Certificates certified by independent Certificate Authorities can cost several hundred dollars a year, which wasn't really an option for publishing this free software. The certificate that signs Mars MOLA Viewer was obtained through a free trial certificate program from the Thawte certificate authority. Since this is a free program, the identification on the certificate says only "Thawte Freemail Member." Because anyone in the program might have a certificate with the same identification, you have to look at the details of the certificate to confirm that the certificate is owned by antlersoft. In the details, the certificate will show the e-mail address  Also, since this program was first published, the certificate has expired.  It still remains trustworthy, however.

Source Code

The source code for Mars MOLA Viewer is available in this archive. It is distributed under the terms of the GPL.  Current version: MD20060802

The 3D Graphics portion of Mars MOLA Viewer is based on the work of Emil Persson, AKA Humus--in particular his Infinite Terrain demo. Visit his website.

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