This collection of activities will allow you to journey with your students to these distant explosions, by following exactly the same procedures used by today's astronomers. Your students will review some basic physics concepts about light, learn about redshifted spectra and Hubble's Law, and use them to find out how far away, and how powerful, gamma ray bursts truly are. Your students will "be the astronomer!"
Students will work with a real optical spectrum of a gamma ray burst afterglow taken at the Keck Observatory. They will measure the shifts of spectral lines, deduce the velocity of the astronomical object, and then use Hubble's Law to get its distance. Finally, if we know how far away an object is, and how much energy it deposited on our detector, we can calculate how much energy was emitted at the source, using the "one over r-squared" fall-off relation of light.
These activities reinforce basic physics concepts (light, the electromagnetic spectrum) and chemistry concepts (spectral lines, spectroscopy). Students experience how these concepts are cast in a mathematical form, and how the concepts combine to answer a fundamental question about a mysterious phenomenon in our universe (process of science). They are most appropriately used in a 11th or 12th grade physics or chemistry class, but can be modified for use in a mathematics class, or with bright, motivated younger students.
