Before You Begin

There are four fundamental tasks to this lab:
  1. Find a pre-assigned number of Cepheid variables in the galaxy M100.
  2. Use the periods and average apparent magnitude of the Cepheids, and the Period-Luminosity relation, to determine the distance to M100.
  3. Estimate the Hubble constant, which represents the current rate of expansion of the universe.
  4. Use your derived value of the Hubble constant to estimate the age of the universe.
Along the way, you will:

Plan on 2 to 3 hours to do the lab. Note: The lab sheet does not have all the information you need to do the lab. Please be sure to read the associated Web pages as you work through the lab sheet.

Hardware and software requirements:

Other requirements:

Many links to external Web pages have been provided for those who are interested. These optional pages are intended to introduce some of the many fine astronomy Web pages.

The lab is intended to be fun. You should feel free to do the lab at whatever pace you wish. If you find yourself getting bored with background material in the first sections, move on to the next section. You can always go back to previous pages to learn any background you missed.

On to Measuring Cosmic Distances

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