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Guide Index

Out of Thin Air

NASA's Way to Mars

Why Go to Mars?

We're on Our Way

Houston, We've Had a Problem!

Getting There

Viewer Challenge
in the classroom

Journey to Mars: Why Go to Mars?

A four-pound rock that left Mars 16 million years ago may hold the clues to ancient life on the planet. The rock is one of 13 Mars meteorites found on Earth. These rocks may contain clues to the ancient history of planet Mars, believed to have been a warmer, wetter place over 3 billion years ago. NASA's planetary scientists tell us why they think the Mars rock contains evidence of ancient life.

Curriculum Links
National Science Education Standards
Related Frontiers Shows and Activities
Activity: 3-D Mars



extreme environments, geology, minerals, structure of universe


bacteria, evolution, fossils


science fiction


computer graphics


5-8: Properties and Changes of Properties in Matter
9-12: Structure and Properties of Matter
5-8: Diversity and Adaptations of Organisms
9-12: Biological Evolution
5-8: Structure of the Earth System
9-12: Geochemical Cycles, Origin and Evolution of the Earth System
5-8: History of Science
9-12: Nature of Scientific Knowledge, Historical Perspectives



Scientists studying Mars today enjoy many technological advances early astronomers did not have. One technique, 3-D imaging, was critical to the 1997 Pathfinder mission. A digital stereoscopic camera on the Sojourner rover took pictures of the Martian surface that were coded into radio signals and beamed back to Earth. Ground controllers navigated the rover across the surface using 3-D technology.

One way to view an image in 3-D is to make an anaglyph. Two images of the same subject are used -- one image is tinted red and the other is tinted blue or green. These colored images are stacked upon each other. When you view an anaglyph through red/blue glasses, the red lens cancels out the red image and the blue lens cancels out the blue image. This allows each eye to see a slightly different view, and your brain interprets a 3-D image. In this activity, make a pair of 3-D glasses and use them to view Mars images on the Internet.

picture of 3-D Glasses MATERIALS
  • scissors
  • tape
  • heavy paper stock
  • transparent red plastic
  • transparent blue plastic
  • 3-D comic strips or other images (e.g., Internet sites listed in activity)
NOTE: Use plastic report covers or lens gels used by theater departments for the plastic sheets.


  1. To make 3-D glasses, print out the image on the right and, using a photo copy machine, enlarge the image to fit your head and eyes properly. Trace the image onto heavy stock paper and cut out the eye holes.

  2. Cut out one rectangle each of red and blue plastic, both about the size of a 35 mm slide. Tape one rectangle over each eye window in the glasses, and use your viewers to examine 3-D comics or other images. Can you tell how the distance between red and blue lines affects the apparent depth of the image? (The closer the lines, the further the apparent image.)

  3. Check out these sites for 3-D images of Mars. Or, do your own Internet search using keywords like "Mars," "3-D," "anaglyph" and "Pathfinder":

    See fantastic 3-D color images and find out where to get 3-D glasses at

    The August 1998 issue of National Geographic features an article about Mars and includes 3-D images of the planet (and free 3-D glasses). You can find even more 3-D Mars images in the new book, Mars: Uncovering the Secrets of the Red Planet.

  1. The Mars rock seen on Frontiers was broken off from Mars 16 million years ago, and traveled around in space until 13,000 years ago, when it landed in Antarctica. Look for news reports of other discoveries of Mars meteorites.

  2. Scientific American Frontiers first met exobiologist Jack Farmer on Life's Big Questions (Show 501) in "Are We Alone?" You can read about Farmer's life and microfossil discoveries in his field journal at

  3. Scientists have found evidence of microbes living in extreme environments on Earth, far beneath the surface of the planet and at ocean thermal vents (where microbes survive without sunlight), even in the Antarctic and in Yellowstone's hot springs (some of these microbes are believed to be primitive bacteria called Archaea). What do these findings suggest about the possibility of life on Mars?

  4. Debate the pros and cons of sending robots vs. people to Mars. The late scientist Carl Sagan, an early proponent of Mars exploration, argued for robotic explorations. Find out more about his reasoning. Do you agree or disagree with him?


Scientific American Frontiers
Fall 1990 to Spring 2000
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now a part of Verizon Communications Inc.