PSC 203 – Elementary Astronomy Name ________________________
Spring 2009
Bonus Outside Project, Spectra of Everyday Sources
due date April 30th , 2009
Please check one of the following options and return this form with your project information
_______ I wish to use this project as bonus in-class assignment for PSC 203.
_______ I wish to use this project as bonus homework assignment for PSC 203.
**You may complete 2 observation to earn 1/2 assignment credit. If you complete 4 observations, you
can earn a full assignment credits.
Instructions:
You need to get a pair of the diffraction grating “rainbow glasses” from your instructor to complete this
assignment. Once you have the glasses, you will take this tool home with you, observe common light
sources, and describe your observations. For each light source you observe you will need to answer all
of the questions listed below. It will be easier to see the spectrum if you have very few other light
sources around you and if the background is darker. Answering that you really could not see much at all
is not an acceptable answer. Find a different source that you can see.
Suggestions of possible light sources:
Ordinary light bulb with a filament (glowing wire inside); Compact fluorescent light bulb; Flame from
a candle or fire ; Car headlight; Traffic light (must state if it was red, yellow, or green); Street lamp
(Sodium vapor lamps are more of a yellow white color, Mercury vapor lamps are more of a blue white
color); The Moon; Neon sign (thin glass tubes that glow brightly); Computer screen or television set
To be turned in:
1) This cover sheet
2) Your typed or very neatly written answers to the following questions.
a) What source did you observe?
b) What color does that light source appear to be before you look through the glasses?
c) What colors do you see through the diffraction glasses?
d) What color is the brightest?
e) What colors if any are missing or very faint?
f) Is this an example of a continuous light source or an emission light source?