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Observing the Spectrum of M31

You have elected to observe the spectrum of M31, and compare the locations of spectral lines to those of calcium as seen in a laboratory. Spectra are especially powerful tools in astronomy, and contain much useful information about their sources! Below is the spectrum of M31. The locations of lab spectra of calcium K and H lines are also indicated in black. The corresponding calcium H and K lines from M31 can be seen in absorption. Look carefully in making your comparison. You may find it easier to click on the image, print it, and estimate the Doppler shifted wavelengths using a ruler.

spectrum of M31


Info Click here for more information about spectra and representations of spectra.
Info Why are the hydrogen and Calcium lines not in the right place for this galaxy? Click here for information about the Doppler shift, and how it affects a galaxy's spectrum.
Experiment Return to the beginning and try another approach

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