Astronomy Chapter 17 and 18
A star moving toward the Sun will show
A shift in the spectral lines toward the blue end (as compared to the laboratory positions of these lines)
Who was the astronomer who is the "H" in H-R diagram?
Henry Norris Russel
When an astronomer rambles on and on about the luminosity of a star she is studying, she is talking about:
How much energy that star gives off each second
Which law do astronomers use to determine the masses of the stars in a binary system?
Kepplers Law
Which of the following is a failed star , an object with too little mass to qualify as a star?
a brown dwarf
Which of the following can astronomers learn from studying the spectrum of a star?
all of these
Two stars that are physically associated (rotate around each other in space) are called
binary stars
Which color star is likely to be the hottest?
blue
The rate at which a star or other object emits electromagnetic energy into space per second; the total power output of an object.
luminosity
Two stars have the same luminosity, but star B is three times farther away from us than star A. Compared to star A, star B will look
nine times fainter
An H-R Diagram plots the luminosity of stars against their:
surface temperature
