1
A star’s apparent brightness is based on what?
Its absolute brightness and its distance from Earth
2
Where on an H-R diagram are most stars located?
The main sequence
3
What characteristics are plotted on H-R diagrams?
Luminosity versus surface temperature
4
What letters are in the spectral class?
O B A F G K M
5
What determines a star’s color, luminosity, and temperature?
Mass and composition
6
What happens to stars when they begin fusing elements heavier than hydrogen?
They become giants or supergiants
7
Which of the following characteristics CANNOT be determined using an H-R diagram?
Distance from Earth
8
What is the easiest element for stars to fuse?
Hydrogen
9
Where is our Sun on the H-R diagram?
Main sequence
10
What is a star color?
Yellow, Blue, White