Rendering a Topographic Model into a Surface Plot

An Extension of LFM Activity 1.2

When the Mars Global Surveyor reaches the Red Planet in September 1997, it will assume an orbit and begin "bouncing" a beam of light off the Martian surface by means of the Mars Orbiter Laser Altimeter (MOLA). By measuring the speed at which the reflected pulse returns to the spacecraft, engineers will be able to determine with great accuracy the surface topography.

Live From Mars Activity 1.2 - Mapping the Topography of Unknown Surfaces offers a wonderful modeling activity for your students on the mathematics and science behind the MOLA. As an extension of the Teacher's Guide directions, your students can also render their shoe box measurements into a 3-D computer image.

Software Requirements

Instructions for Rendering into Surface Plot


1. Record all altimeter rod readings on spreadsheet. Be sure numbers entered represent height of surface, not depth of rod.

2. Upon completion of measurements, save spreadsheet data as ASCII Text.

3. Open NIH Image, go to File menu and import spreadsheet data as TEXT.

4. Go to Analyze menu and select Surface Plot.

5. Select grayscale/color.

6. Color of image can be changed by going to Options menu and selecting Color Tables.

Last updated July 25, 1997

Comments and/or questions to Tim McCollum

Return to CyberScience '97