Resource Type
Completion Time
About 1 period
High school and Up
Download, Share, and Remix
Lesley Urasky
Transparent plastic box (must have flat sides and an open top). Acrylic boxes about 6" x 12" x 6" high work well
Aluminum plate, about 5 mm thick, slightly larger than the opening of the box
Black felt (large enough to cover the bottom of the container) or black blotter paper
Gorilla glue (or other adhexive that is solvent resistant)
Black electrical tape
Small Styrofoam cooler lid or shallow insulated box
Dry ice (approximately 1 lb.), crushed
Very intense, concentrated light source (strong flashlight, projector, etc.)
91% Isopropyl alcohol (NOT the 70% commonly found in stores)
Insulated gloves (for handling dry ice)
Gloves (for handling alcohol)
Safety goggles
Physical Science

During Lesley Urasky’s expedition, “Glacial History in Antarctica”, the team collected rock samples which were taken back to the University of Washington to be dated using cosmogenic (exposure) dating. This method of radiometric dating measures the ratio of isotopes of Beryllium (9Be:10Be) produced by the interaction of cosmic rays with minerals in rocks. This lesson will introduce the student to cosmic rays.