9.
(05.03 MC)

Scatter plot (HR Diagram) showing the relationship between the surface temperature of stars (in Kelvin) and their absolute brightness. Absolute brightness is plotted on the y-axis. The scale goes from +15M up to -10M. The surface temperature is plotted on the x-axis. The scale goes from 40,000K down to 2,500K. There is a group of dwarf stars positioned at approximately +10 absolute brightness (M) and 20,000 Kelvin (K). A long chain of main sequence stars are plotted from -10M and 40,000K down to +15M and 1,500K. There is a group of super giant stars located at approximately -7M and 7,500K and a group of giant stars located at 0M and 2,500K.

Part 1: Describe the mass and surface temperature of the supergiant stars.

Part 2: Explain where on the HR diagram you would expect to find a supergiant star based on its physical properties. (10 points)