A new screen saver debuts today showing the "Sojourner" rover, which was launched today on the Mars Pathfinder spacecraft, as it crisscrosses over or navigates around Martian boulders.

The screen saver display is free and available on the Internet for computer users with Windows 3.1 and '95 and Macintosh software. It can be downloaded by accessing the JPL Mars home page at

The software was designed by NASA's Jet Propulsion Laboratory as part of an effort to educate the public about the Mars Pathfinder mission and NASA's decade-long program of Mars exploration. It depicts the 60-centimeter (23-inch) long Sojourner microrover that will drive out onto the surface of Mars to explore the composition of rocks and soil in July 1997. Sojourner is able to hurdle small rocks and steer around those that are too large to scale. The rover features several innovative new technologies, including miniaturized electronics and a six-wheeled "rocker-bogie" suspension system that allows it to climb over rocks almost as tall as itself.

The new screen saver also includes dramatic scenes of some geologically intriguing regions on Mars that will be photographed by NASA's Mars Global Surveyor orbiter, which was launched on Nov. 7, 1996, from NASA's Cape Canaveral Air Station, FL.

Surveyor, which will reach Mars on Sept. 12, 1997, will orbit the planet for one full Martian year, the equivalent of 687 Earth days, taking new images of Mars and making scientific measurements of its atmosphere and surface. JPL's new screen saver sequence depicts various dramatic images of Mars, showing increasing detail of some prominent features such as a towering volcano called Olympus Mons and a huge canyon known as Valles Marineris. The closing sequence shows a Viking photograph of Pathfinder's targeted landing site on an ancient flood plain known as Areas Valles.

"The images of Mars were rendered here at JPL on our CRAY T3D parallel supercomputer," said Dr. Carl Kukkonen, manager of JPL's Supercomputing Project. "Scenes like this helped the Mars Exploration Program Office at JPL to determine the most ideal landing site for the Pathfinder mission."

"This screen saver is another exciting tool that any Windows or Macintosh user can have to learn more about NASA's Mars exploration program," added Dr. Cheick Diarra, manager of the Mars Education and Public Outreach Office at JPL.

The screen saver is available in the Windows 3.1, Windows '95 and Macintosh formats to computer users with any version of the "After Dark" screen saver software produced by Berkeley Systems, Inc. The screen saver was a joint effort of JPL and Berkeley Systems of Berkeley, CA, developer of After Dark screen saver software, which can be downloaded from the Internet by using the following address:

The Mars exploration program and the Supercomputing Project at JPL supported development of the new Mars exploration screen saver with funding from NASA's Office of Space Science, Washington, D.C.

News Media Contact