Exam I Material

Question 1

Two stars have the same luminosity. Star X is spectral type F, while Star Y is spectral type K. Therefore, Star X is larger in radius than Star Y.

True or False.

Answer 1

False.

Question 2

Who is the astronomer indicated by the “H” in the H-R diagram?

a) Hubble
b) Henry
c) Hertzsprung
d) Huggins
e) Hoyle

Answer 2

c) Hertzsprung

Question 3

A star has spectral lines of molecules in its atmosphere. Which of the spectral types listed below is it most likely to belong to?

a) A
b) B
c) G
d) M
e) O

Answer 3

d) M

Question 4

Which type of star has the strongest Balmer lines of hydrogen?

a) A
b) B
c) G
d) M
e) O

Answer 4

a) A

Question 5

This person reorganized the spectral classification scheme into the one we use today and personally classified over 400,000 stars.

a) Annie Jump Cannon
b) Williamina Fleming
c) Cecilia Payne-Gaposchkin
d) Henry Draper
e) Edward Pickering

Answer 5

a) Annie Jump Cannon

Question 6

Which of the following statements about apparent and absolute magnitudes is true?

a) The magnitude system that we use now is based on a system used by the ancient Greeks over 2,000 years ago that classified stars by how bright they appeared
b) A star with apparent magnitude 1 is brighter than one with apparent magnitude 2
c) The absolute magnitude of a star is another measure of its luminosity
d) A star’s absolute magnitude is the apparent magnitude it would have if it were at a distance of 10 parsecs from Earth
e) All of the above are true

Answer 6

e) All of the above are true

Question 7

The faintest star visible to the naked eye has an apparent visual magnitude of about:

a) 10
b) 6
c) 1
d) 0
e) -6

Answer 7

b) 6

Question 8

On a Hertzsprung-Russell diagram, where on the main sequence would we find stars that have the greatest mass?

a) Upper right
b) Lower right
c) Upper left
d) Lower left
e) There are no trends in mass on the main sequence

Answer 8

c) Upper left

Question 9

The spectral sequence in order of decreasing temperature is:

a) OFBAGKM
b) OBAGFKM
c) OBAFGKM
d) ABFGKMO
e) BAGFKMO

Answer 9

c) OBAFGKM

Question 10

A planet is detected via the Doppler technique. The repeating pattern of the star’s radial velocity curve tells us:

a) The planet’s size
b) The planet’s mass
c) The planet’s density
d) The orbital period of the planet
e) The orbital eccentricity of the planet

Answer 10

d) The orbital period of the planet