Below are three spectra. The first is the spectrum of a
typical star. The second is the spectrum of a typical galaxy. The third
is the spectrum of something else - an object like the ones you saw
in Exercise 1.
What are the differences between the first two spectra and the third?
What are some of the different emission and absorption
lines you see? Do they look like thermal radiation sources or
non-thermal radiation sources? Click on any of the images for a
full size version.