Astronomy TOP Study Guide Questions and CORRECT Answers

To get started, click on the blue Cepheids link on the main screen of the Interactive Figure. The Interactive Figure (in red) shows a graph of the Cepheid period-luminosity relation. This graph indicates that __________. - Cepheids with longer periods have higher luminosities A Cepheid with a period of 30 days has an average luminosity that is about __________ times the luminosity of the Sun. - 10,000 Click on the blue "Cepheid" label, then click the label on the bottom of the Interactive Figure that reads "Cepheids as Standard Candles" to bring up the next screen. Read the instructions that appear in the upper left hand corner and study the animation. What actually causes a Cepheid to vary in apparent brightness? - The Cepheid varies in radius, and its luminosity is greater when its radius is larger.