This activity is designed for students to apply their knowledge of mathematics and physics to "real life" situations. Students are presented with the situation that they are on a camping trip and wish to know the wavelength emitted by a star. How can they measure this? They are given a laser to simulate the starlight and use a diffraction grating and a ruler to determine the wavelength of its light. They compare their results with accepted wavelengths given on the electromagnetic spectrum chart in their text.