On/ine Lab: Exploring the World with Spectroscopy Purpose e View and photograph the spectra of many familiar light sources. e Interpret spectra to identify unknown light sources. What You Will Need You will need the following ACDorDVD. Itdoesn't matter if it is new or used, but don't use one that contains needed information because you may scratch it. (Though If you handle it carefully there is a good chance it will still be useable after you are done.) e Scissors and tape (or glue). e Plain printer paper will work fine, but if you want to get fancy, you may use printable cardstock, or a small cardboard box you already have, if it is close in size to the finished object, at least 12.5 x9x3cem (5x3.75 x 1.25 inches). e Acamera is useful to record the spectra you find, or you will need to describe and draw them. Preparation e \\View the online lecture 05-Matter and Light, especially the sections on different types of spectra. Background In the mid-1800s, scientists discovered that when they heated up different gasses until they were glowing hot, each particular gas glowed with its own unique colors of light. We can get even more information from these colors when we break the light up into a spectrum or rainbow. In this lab you will use a simple but effective spectroscope made with an old CD or DVD. (A professional astronomer would use a diffraction grating, but you're less likely to have one of those lying around the house!) A diffraction grating or a CD makes a spectrum because it has many parallel, tightly- spaced lines or tracks on its surface. You may already have noticed this effect when you see the colorful reflections from the surface of a CD. Our spectroscope will enclose the CD in a little box with a slit to let light in at the right angle, and a viewing window so you can see the spectrum against a shaded background for best contrast and visibility.