Doppler Shift/Hubble's Law Lab

In this activity, students use spectra from real galaxies to calculate the doppler shift and plot a graph of recession velocity against distance from Earth to find the Hubble constant.
Paper, computer, offline and online versions of the lab with instruction sheets, follow up questions and extension questions for both Alevel and GCSE students.

Students will use real absorption and emission spectra from galaxies to:

• Identify the emission and absorption lines for H, Ca, Ca and read off their observed wavelengths either online using clickable spectra or offline on worksheets
• Calculate the red shift either by hand or automatically from a spread sheet
• Find the distance the galaxy is from Earth either using data, a clickable image and a spreadsheet or a clickable image
• Plot a graph of recession velocity against distance, either on a worksheet or auto plotting from excel
• Find the Hubble Constant from the gradient of their graph
• Answer follow up questions about big bang evidence, to find the age of the universe etc

This activity uses the data and clickable spectra from: http:// depts. washington. edu/astroed/HubbleLaw/galaxies.html

The galaxy spectra were obtained by Robert C. Kennicutt Jr. of the University of Arizona, and are published in The Astrophysical Journal Supplement Series, volume 79, pages 255-284, 1992, and are also available on the WWW. The digital images of the galaxies have been extracted from the CD-ROM version of the Palomar Observatory Sky Survey, which was produced under NASA contract by the Space Telescope Science Institute, operated by AURA, Inc.
I have cherry picked the data from this lab and chosen the galaxies with the clearest emission and absorption lines that will produce a Hubble constant of approx. 70km/s/Mpc.
Washington University Astronomy Department are redoing their website and so links might change.