It is now practical for undergraduate students to carry out a laboratory exercise in which they determine an approximate age for the universe using their own data. Because of the wide availability and excellent performance of charge-coupled device cameras designed for astronomy, a relatively small telescope with a modest spectrograph is sufficient to carry out the necessary observations. The age determination rests on a measurement of the Hubble constant, which, in this experiment, is derived from the measured distance and velocity of recession of a single galaxy. The distance is determined from an image of the galaxy, while the velocity is obtained from a measurement of the redshift of the spectrum of the galaxy. Examples of such observations made at a small college observatory are presented and the extraction of an estimate of the age of the universe from those data is described.

Topics
Doppler effect, Hubble's law, Galaxies, Telescopes, Spectral methods, Charge coupled devices, Education, Laboratories
1.
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© 1999 American Association of Physics Teachers.
1999
American Association of Physics Teachers
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