Astro 11
Lab 9

• In this lab, you will determine how stellar properties, such as temperature, luminosity, spectral type, and radius are related. You will make use of a Hertzsprung-Russell diagram to understand the relations between the properties mentioned above.


• You will need a calculator for some questions in this lab, so don't forget to bring it.


• For question b, do not use Sirius B as an indicator of how temperature goes with spectral type. It is a different type of star that does not follow the same relation.


• For question e, another way to think about it is if you could travel to any other part of the galaxy, and take a survey of the stars in that part, which of the two groups of stars would more closely resemble that survey?


• For question g, you will need the inverse-square law of light (f = L/4pd²), from Lab 8.


• When putting stars on the HR diagram into different categories, make sure to not leave any out. There should be no stars left out after you assign all the different groups.


• This lab is quite concept intensive. Take a few moments to organize the concepts you learned before you write your summary.