Analyzing Reflectance Spectra of Minerals and Planetary Surfaces

Michael Urban

Bemidji State University

Introductory geoscience students. Used in a planetary science course.

Students practice using the ALTA® II reflectance spectrometers by completing Treiman's "Activity 3 – Taking a Reflectance Spectrum" from the Lunar and Planetary Institute's ALTA® Reflectance Spectrometer: Introduction and Classroom Lessons (2000) in a prior class period.

Part 1:
During class, students use spectrometers to collect data about mineral hand samples; graph data using spreadsheet software; compare and contrast the graphs they've generated to USGS spectral library reflectance graphs for the same minerals; attempt to identify "unknown" mineral samples by matching student-generated graphs to USGS spectral library graphs.

Part 2:
Students examine reflectance graphs for identified planetary bodies in the solar system; attempt to determine compositional characteristics of "unknown" planetary bodies based on reflectance spectra; identify probable planetary bodies (from options provided) based on the reflectance spectra. Students are asked to provide rationales for all attempted identifications. The activity provides students an opportunity to learn more about the importance of light in planetary science by enabling them to practice interpreting reflectance spectra, use mineral reflectance spectra to learn about the composition of planetary bodies, and apply representative techniques to solving scientific problems.

Satisfactory completion of the lab worksheet, successful use of spectrometers and spreadsheet software in class, discussion (formal and informal), and test questions related to activity.