Lesson Plan: Using Cepheid Variable Stars to Measure Distances to other Galaxies
This lesson plan includes the objectives, prerequisites, and exclusions of the lesson teaching students how to use the relation between the period of variation and the mean absolute magnitude of Cepheid variable stars to determine how far away they are.
Objectives
Students will be able to
- understand that the mean absolute magnitude of a Cepheid variable star is related to its period of variation,
- use to relate the mean absolute magnitude, , to the period, , of a Cepheid variable star,
- use and to work out the distance to a Cepheid variable star.
Prerequisites
Students should already be familiar with
- apparent and absolute magnitudes,
- light-years and parsecs,
- .
Exclusions
Students will not cover
- any other methods of measuring distances to other galaxies,
- proper motion,
- parallax,
- redshift.
