Astronomy a beginners guide to the universe 8th CHaisson mcmillan chapter 10 clicker questions

Astronomy
A BEGINNER’S GUIDE
TO THE UNIVERSE
EIGHTH EDITION

CHAPTER 10

Measuring the Stars
Clickers

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Question 1
Stellar parallax is used to measure the

a)
b)
c)
d)
e)

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sizes of stars.
distances of stars.
temperatures of stars.
radial velocity of stars.
brightness of stars.

Question 1
Stellar parallax is used to measure the

a)
b)
c)
d)
e)

sizes of stars.
distances of stars.
temperatures of stars.
radial velocity of stars.
brightness of stars.

Explanation: Parallax can be used to
measure distances to stars accurately
to about 200 parsecs (650 light-years).

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Question 2
The angle of stellar parallax for a star gets larger as the

a)
b)
c)
d)
e)

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distance to the star increases.
size of the star increases.
size of the telescope increases.
length of the baseline increases.
wavelength of light increases.


Question 2
The angle of stellar parallax for a star gets larger as the

a)
b)
c)
d)
e)

distance to the star increases.
size of the star increases.
size of the telescope increases.
length of the baseline increases.
wavelength of light increases.

Explanation: Astronomers typically make
observations of nearby stars 6 months
apart, making the baseline distance
equal to 2 AU (astronomical units).

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Question 3
You can best model the size and distance relationship of our Sun and the next nearest star using

a)
b)
c)
d)
e)

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one tennis ball here and one on the Moon.
two beach balls separated by 100 city blocks.
two grains of sand 100 light-years apart.
two golf balls 100 km apart.
two baseballs 100 yards apart.


Question 3
You can best model the size and distance relationship of our Sun and the next nearest star using

a)

one tennis ball here and one
on the Moon.

b)

two beach balls separated
by 100 city blocks.

c)

two grains of sand 100
light-years apart.

d)
e)

two golf balls 100 km apart.
two baseballs 100 yards apart.

Explanation: The Sun is about 1 million miles in diameter. The next nearest star is about 25 million times farther
away.

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Question 4
A star’s proper motion is its

a)
b)

true motion in space.
apparent shift as we view from
opposite sides of Earth’s orbit

every 6 months.

c)

annual apparent motion
across the sky.

d)

motion toward or away from
us, revealed by Doppler shifts.

e)

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orbital motion around the Galaxy.


Question 4
A star’s proper motion is its

a)
b)

true motion in space.
apparent shift as we view from
opposite sides of Earth’s orbit
every 6 months.

c)

annual apparent motion
across the sky.

d)

motion toward or away from
us, revealed by Doppler shifts.

e)

orbital motion around the Galaxy.

Explanation: A star’s “real space motion” combines its apparent proper motion with its radial motion toward or away
from Earth.
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Question 5
In the stellar magnitude system invented by Hipparchus, a smaller magnitude indicates a _____ star.

a)
b)
c)
d)
e)

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brighter
hotter
cooler
fainter
more distant


Question 5
In the stellar magnitude system invented by Hipparchus, a smaller magnitude indicates a _____ star.

a)
b)
c)
d)
e)

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brighter
hotter
cooler
fainter
more distant


Question 6
A star’s apparent magnitude is a number used to describe how our eyes measure its

a)
b)

c)
d)
e)

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distance.
temperature.
brightness.
absolute luminosity.
radial velocity.


Question 6
A star’s apparent magnitude is a number used to describe how our eyes measure its

a)
b)
c)
d)
e)

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distance.
temperature.
brightness.
absolute luminosity.
radial velocity.

Question 7
The absolute magnitude of a star is its brightness as seen from a distance of

a)
b)
c)
d)
e)

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1 million kilometers.
1 astronomical unit.
1 light-year.
10 parsecs.
10 light-years.


Question 7
The absolute magnitude of a star is its brightness as seen from a distance of

a)
b)
c)
d)
e)

1 million kilometers.
1 astronomical unit.

1 light-year.
10 parsecs.
10 light-years.

Explanation: Astronomers use
a distance of 10 parsecs
(about 32 light-years) as a
standard for specifying and
comparing the brightnesses of stars.

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Question 8
Which of the following quantities do you need in order to calculate a star’s luminosity?

a)
b)
c)
d)
e)

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Apparent brightness (flux)
Doppler shift of spectral lines
Color of the star
Distance to the star
Both a and d are correct.

Question 8
Which of the following quantities do you need in order to calculate a star’s luminosity?

a)
b)
c)
d)
e)

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Apparent brightness (flux)
Doppler shift of spectral lines
Color of the star
Distance to the star
Both a and d are correct.


Question 9
What are the two most important intrinsic properties
for classifying stars?

a)
b)
c)
d)
e)

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Distance and surface temperature
Luminosity and surface temperature
Distance and luminosity
Mass and age
Distance and color


Question 9
What are the two most important intrinsic properties
for classifying stars?

a)

Distance and surface
temperature

b)

Luminosity and surface
temperature

c)
d)
e)

Distance and luminosity
Mass and age
Distance and color

Explanation: The H–R diagram plots
stars based on their luminosities and
surface temperatures.
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Question 10
Wien’s law tells us that the hotter an object, the _____ the peak wavelength of its emitted light.

a)
b)
c)
d)
e)

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longer
more green
heavier
shorter
more constant


Question 10
Wien’s law tells us that the hotter an object, the _____ the peak wavelength of its emitted light.

a)
b)
c)

d)
e)

longer
more green
heavier
shorter
more constant

Explanation: Wien’s law
states that hotter stars
appear more blue in color,
and cooler stars appear
more red in color.

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Question 11
We estimate the surface temperature of a star by using

a)
b)

its color.
the pattern of absorption
lines in its spectrum.

c)
d)

Wien’s law.
differences in brightness
as measured through
red and blue filters.

e)

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All of the above are used.


Question 11
We estimate the surface temperature of a star by using

a)
b)

its color.
the pattern of absorption
lines in its spectrum.

c)
d)

Wien’s law.
differences in brightness
as measured through
red and blue filters.

e)

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All of the above are used.


Question 12
Which spectral classification type corresponds to a star like the Sun?

a)
b)
c)
d)
e)

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O
A
F
G
M


Question 12
Which spectral classification type corresponds to a star like the Sun?

a)

b)
c)
d)
e)

O
A
F
G
M

Explanation: The OBAFGKM
classification scheme is based
on absorption lines.

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