 Unit 7: Astronomy and Space ExplorationActivity 2: Fingerprints of the Stars (SI GLEs: 6, 8, 13; ESS GLE: 37)
CC: Students often ask how astronomers know so much about the composition of stars. Scientific instruments, such as the sprectroscope, have revealed a wealth of information about the Sun and other stars through its fingerprint, or spectrum. Using diffraction grating or spectroscopes (possibly constructed by the students-see Web site resource references for construction directions), the spectral patterns of various light sources will be analyzed. Students will accurately record order, color, and width of the visible spectral lines. Sources for spectral analysis may include simple flame tests, spectrum or gas tubes (H, He, Hg, Ne, O, etc), fluorescent lights, mercury vapor or sodium streetlights (often found on campus). Each gas has a unique spectrum. Some spectroscopes have calibrated scales that allow spectral lines to be analyzed by wavelengths (angstroms). Students may compare the detection of elements in space to bar codes used in product identification. Spectral studies of stars has also led to a greater understanding of the movement of stars and the expansion of the universe. To research this understanding, students may be assigned topics, such as the Doppler effect, absorption spectra, bright-line spectra, red shift, blue shift, and the Hubble Space Telescope.
How To Build A Spectroscope http://www.exploratorium.edu/spectroscope/
Comprehensive Curriculum suggested websites for spectroscope construction are found at: http://stardate.org/teachers/activities/spectroscope.html http://www.opticsforkids.com/resources/6_Constructing_Spectroscope.pdf |