Problem Set #4
Reading: Chapters 10 and 13
Note. Please feel free to use Excel or other computer programs to complete this assignment.
1. Page 2 carries a list of stars together with their apparent magnitudes, distances, and temperatures. For each one calculate the absolute magnitude and enter it in the blank column labeled M. Use the formula:
where d is the distance in parsecs.
Example, Altair -- m=0.76, d=5.1pc
2. Use interpolation from the following table to estimate the spectral type of each star. Enter type in column Sp of page 2. (If you don't know what interpolation means, look it up!)
Spectral Type Temperature (K)
5. Use the fact that the Sun has an absolute magnitude of 4.5 and a luminosity of 4x1033ergs/s to scale to other stars. Use the Stefan-Boltzmann Law to calculate the radius of Sirius A, Sirius B, and Antares.
Star m d (pc) T (K) M Sp Type (MGW)