Martha Gilmore, Professor of Earth and Environmental Sciences, has introduced the science of Remote Sensing to Wesleyan students (E&ES 326, http://mgilmore.web.wesleyan.edu/wescourses/2001s/ees326/01/326home.htm). In the process, she has learned valuable lessons on how to manage a data-intensive course taught in an interactive computer classroom. “Remote sensing” generally refers to collecting data about a phenomenon from a distance, and subsequent analyses of the data. More specifically, data are derived using instrumentation such as cameras and various spectrometers that record information about the electromagnetic spectrum reflected off or absorbed by an environment. Examples include aerial and satellite photography, and infrared and radar imaging.

"A course on remote sensing, serves a variety of interests in Earth and Environmental Sciences, since it has applications for geologists and environmentalists, as well as for urban and regional planners."

Gilmore, a planetary geologist whose specialty is Mars, is looking for evidence of water on Mars. She came to Wesleyan in the Fall of 2000 from NASA’s Jet Propulsion Laboratory in Pasadena, CA. Her primary research tools are satellite images and high-end visualization software that she uses to analyze Mars Global Surveyor mission data. “A course on remote sensing,” Gilmore explains, “serves a variety of interests in Earth and Environmental Sciences, since it has applications for geologists and environmentalists, as well as for urban and regional planners.” Her software of choice is ENVI (Environment for Visualizing Images) by Research Systems, Inc. While not the easiest application to learn, she considers it the most powerful available for remote sensing.

Her experiences with the technology are instructive beyond this particular course. “When technology is a focus of course content, rather than a complement or an enhancement, there’s definitely extra pressure on the instructor,” says Gilmore. “You’re subject to things breaking down or to the server being unavailable.” However, she notes that after the first few weeks of the class, technology issues settle down. She teaches the class in SC74, the Windows Interactive Classroom, which has 20 student stations, plus the instructor’s computer. She chose to use ENVI on woodstock.wesleyan.edu, the Wesleyan UNIX compute server (UNIX is a multi-user environment in which multiple concurrent users share the processing power of the system). They run the program using WebTermX, an X Windows System application that provides a graphical user interface to ENVI, rather than having to use a command-line interface. By using ENVI under UNIX, the class can more easily share the very large data files (as large as 600MB) typical of remote sensing computing projects. Gilmore posts the data files in a special shared directory on woodstock so that everyone in the class has access to the files simultaneously.

In the first iteration of the class, Gilmore found that because the class was so large, pairing up students worked better than having them each work on their own. Because not all the students were computer-savvy, they were better able to help each other learn the new technology by working in pairs. This also made it easier for her to help them, since there were fewer stations to visit when checking on the students’ progress. With an eye to permitting more interaction with her students, Professor Gilmore is now limiting the class size to fewer than 20 students, which is less than the number of computer stations in SC74.

For class projects, Gilmore gives the students a number of scenarios or questions to explore using currently held Landsat, radar, and thermal data from Earth. These include looking at deforestation rates and patterning in Brazil, identifying types of land use in Nigeria, and describing changes in Mono Lake, California over a period of three seasons. Gilmore is coordinating with Yale University and University of Connecticut to share among the three universities any public domain datasets they purchase individually. Her data collection can be accessed by the Wesleyan community at: http://www.wesleyan.edu/~mgilmore/ http://wescourses/2001s/ees326/01/datafront.htm