Question 1

Which one of the following does not change due to the precession of Earth's spin axis?

Accepted Answer

A) the right ascension of a typical star 
B) the declination of a typical star 
C) the date of the vernal equinox 
D) the definition of the zero of the system of right ascension 
A) the right ascension of a typical star 
B) the declination of a typical star 
C) the date of the vernal equinox 
D) the definition of the zero of the system of right ascension

Question 2

The difference between 1 second of sidereal time and 1 second of solar time is:

Accepted Answer

A) very small but variable because of the variable motion of Earth in its orbit. 
B) 0, since they are defined to be equal. 
C) a very small but finite and fixed interval of time. 
D) very large, because 1 sidereal second measures a fraction of 1 year while 1 solar second measures the same fraction of 1 solar day. 
A) very small but variable because of the variable motion of Earth in its orbit. 
B) 0, since they are defined to be equal. 
C) a very small but finite and fixed interval of time. 
D) very large, because 1 sidereal second measures a fraction of 1 year while 1 solar second measures the same fraction of 1 solar day.

Question 3

In winter in the southern hemisphere, the Sun will rise on the:

Accepted Answer

A) northwestern horizon. 
B) northeastern horizon. 
C) southwestern horizon. 
D) southeastern horizon. 
A) northwestern horizon. 
B) northeastern horizon. 
C) southwestern horizon. 
D) southeastern horizon.

Question 4

Suppose Earth's rotation axis were straight up and down with respect to the plane of the ecliptic and not tilted. How would a person exactly at the north pole view the Sun?

Accepted Answer

A) The Sun would always be below the horizon and never visible. 
B) The Sun would always be visible on the horizon. 
C) The Sun would be visible for half the year, as is the case now. 
D) The Sun would be visible for more than half the year, but not for the whole year. 
A) The Sun would always be below the horizon and never visible. 
B) The Sun would always be visible on the horizon. 
C) The Sun would be visible for half the year, as is the case now. 
D) The Sun would be visible for more than half the year, but not for the whole year.

Question 5

The time of autumnal equinox, about September 21, is what season for Australians in the southern hemisphere?

Accepted Answer

A) beginning of spring 
B) middle of winter 
C) middle of summer 
D) beginning of autumn or fall 
A) beginning of spring 
B) middle of winter 
C) middle of summer 
D) beginning of autumn or fall

Question 6

Compared with its appearance to a person in mid-latitude northern latitudes, how will the constellation Orion appear to an observer in Australia?

Accepted Answer

A) exactly the same since the stars of Orion are very far away from Earth 
B) upside down but with the same orientation of stars 
C) upside down and inverted left to right, a mirror image of that seen in the northern hemisphere 
D) same way up but inverted left to right 
A) exactly the same since the stars of Orion are very far away from Earth 
B) upside down but with the same orientation of stars 
C) upside down and inverted left to right, a mirror image of that seen in the northern hemisphere 
D) same way up but inverted left to right

Question 7

Cygnus appears high in the sky at midnight in July. Andromeda appears high in the sky at midnight in September. (See Figure 2-5 of Universe, 11th ed.) Where is Andromeda at midnight in July?
​
  ​

Accepted Answer

A) It is still high in the sky at midnight. 
B) It has moved to the western horizon. 
C) It has moved to the eastern horizon. 
D) It is high in the sky at noon and is thus not visible. 
A) It is still high in the sky at midnight. 
B) It has moved to the western horizon. 
C) It has moved to the eastern horizon. 
D) It is high in the sky at noon and is thus not visible.

Question 8

The tropical year is about 20 minutes shorter than the sidereal year. What does this tell you about precession?

Accepted Answer

A) The vernal equinox moves eastward along the ecliptic. 
B) The vernal equinox moves westward along the ecliptic. 
C) The vernal equinox remains fixed on the ecliptic, but the Sun progressively changes its apparent position against the background stars from one sidereal year to the next. 
D) This time difference has nothing to do with the precession of the equinoxes. 
A) The vernal equinox moves eastward along the ecliptic. 
B) The vernal equinox moves westward along the ecliptic. 
C) The vernal equinox remains fixed on the ecliptic, but the Sun progressively changes its apparent position against the background stars from one sidereal year to the next. 
D) This time difference has nothing to do with the precession of the equinoxes.

Question 9

The declination of a star is a measure of its:

Accepted Answer

A) position above the observer's horizon along a great circle passing through the observer's zenith. 
B) time of rising above the horizon. 
C) position along the celestial equator. 
D) position north or south of the celestial equator along a great circle passing through the north and south celestial poles. 
A) position above the observer's horizon along a great circle passing through the observer's zenith. 
B) time of rising above the horizon. 
C) position along the celestial equator. 
D) position north or south of the celestial equator along a great circle passing through the north and south celestial poles.

Question 10

The celestial coordinates of the star γ Persei are right ascension 3h 03m, declination +53°; the coordinates of the star ρ Persei are right ascension 3h 03m, declination +39°. Measured along the shortest angle in the sky between the two stars, γ Persei is:

Accepted Answer

A) west of ρ Persei. 
B) north of ρ Persei. 
C) south of ρ Persei. 
D) east of ρ Persei. 
A) west of ρ Persei. 
B) north of ρ Persei. 
C) south of ρ Persei. 
D) east of ρ Persei.

Question 11

The tilt of Earth's spin axis to the direction perpendicular to the ecliptic plane (known as the ecliptic pole) is:

Accepted Answer

A) variable between 0° and 23.5° over each 3-month season. 
B) 0°. 
C) 23.5°. 
D) 90°. 
A) variable between 0° and 23.5° over each 3-month season. 
B) 0°. 
C) 23.5°. 
D) 90°.

Question 12

The declination of Polaris, the North Star, when viewed from a location 35° north of the equator, is:

Accepted Answer

A) 0°. 
B) 35°. 
C) 55°. 
D) 90°. 
A) 0°. 
B) 35°. 
C) 55°. 
D) 90°.

Question 13

At a certain time the star straight overhead has a right ascension of 2 hours and 30 minutes. One hour later this same star will have a right ascension of:

Accepted Answer

A) 1 hour and 30 minutes. 
B) 2 hours and 30 minutes. 
C) 3 hours and 30 minutes. 
D) 4 hours and 30 minutes. 
A) 1 hour and 30 minutes. 
B) 2 hours and 30 minutes. 
C) 3 hours and 30 minutes. 
D) 4 hours and 30 minutes.

Question 14

Over what range of declination will stars be circumpolar (i.e., be visible at any time of the night on any night of the year) for an observer at 30° north latitude?

Accepted Answer

A) 60° to 90°N and 60° to 90°S 
B) 60° to 90°N 
C) 30° to 90°N 
D) 0° to 30°N 
A) 60° to 90°N and 60° to 90°S 
B) 60° to 90°N 
C) 30° to 90°N 
D) 0° to 30°N

Question 15

The celestial coordinates of the star ζ Leonis are right ascension 10h 16m, declination +24°; the coordinates of the star λ Ursae Majoris are right ascension 10h 16m, declination +43°. Measured along the shortest angle in the sky between the two stars, ζ Leonis is:

Accepted Answer

A) west of λ Ursae Majoris. 
B) north of λ Ursae Majoris. 
C) east of λ Ursae Majoris. 
D) south of λ Ursae Majoris. 
A) west of λ Ursae Majoris. 
B) north of λ Ursae Majoris. 
C) east of λ Ursae Majoris. 
D) south of λ Ursae Majoris.

Question 16

In its motion across the sky against the background stars in the course of a month, the Moon appears to move about:

Accepted Answer

A) 0.5° per day, its own diameter, from west to east. 
B) 1.0° per day, twice its diameter, from west to east. 
C) 0.5° per hour, its own diameter, from east to west. 
D) 0.5° per hour, its own diameter, from west to east. 
A) 0.5° per day, its own diameter, from west to east. 
B) 1.0° per day, twice its diameter, from west to east. 
C) 0.5° per hour, its own diameter, from east to west. 
D) 0.5° per hour, its own diameter, from west to east.

Question 17

To navigators in the northern hemisphere, their latitude in degrees is equal to:

Accepted Answer

A) 15 times the number of hours since the sun set. 
B) the angle between their meridian and the north celestial pole. 
C) the angle between the north celestial pole and their zenith. 
D) the angle between the north celestial pole and their northern horizon. 
A) 15 times the number of hours since the sun set. 
B) the angle between their meridian and the north celestial pole. 
C) the angle between the north celestial pole and their zenith. 
D) the angle between the north celestial pole and their northern horizon.

Question 18

The Moon's equatorial plane is nearly the same as:

Accepted Answer

A) Earth's equatorial plane. 
B) the ecliptic. 
C) the plane passing through both poles and the zenith (for an observer on Earth). 
D) the plane passing through both poles and the vernal equinox (for an observer on Earth). 
A) Earth's equatorial plane. 
B) the ecliptic. 
C) the plane passing through both poles and the zenith (for an observer on Earth). 
D) the plane passing through both poles and the vernal equinox (for an observer on Earth).

Question 19

What is the right ascension of the Sun?

Accepted Answer

A) 0 hours 
B) 12 hours 
C) a number that changes only very slowly because of precession 
D) a number that changes significantly over a day 
A) 0 hours 
B) 12 hours 
C) a number that changes only very slowly because of precession 
D) a number that changes significantly over a day

Question 20

Sirius is the brightest star in the night sky. You watch it set behind the western horizon about 2 A.M. in the middle of February. About what time will it set in the middle of March?

Accepted Answer

A)  10 P.M. 
B)  midnight 
C)  2 A.M. 
D)  4 A.M. 
A)  10 P.M. 
B)  midnight 
C)  2 A.M. 
D)  4 A.M.

Exam 2: Knowing the Heavens

Which one of the following does not change due to the precession of Earth's spin axis?

The difference between 1 second of sidereal time and 1 second of solar time is:

In winter in the southern hemisphere, the Sun will rise on the:

Suppose Earth's rotation axis were straight up and down with respect to the plane of the ecliptic and not tilted. How would a person exactly at the north pole view the Sun?

The time of autumnal equinox, about September 21, is what season for Australians in the southern hemisphere?

Compared with its appearance to a person in mid-latitude northern latitudes, how will the constellation Orion appear to an observer in Australia?

Cygnus appears high in the sky at midnight in July. Andromeda appears high in the sky at midnight in September. (See Figure 2-5 of Universe, 11th ed.) Where is Andromeda at midnight in July? ​ ​

The tropical year is about 20 minutes shorter than the sidereal year. What does this tell you about precession?

The declination of a star is a measure of its:

The celestial coordinates of the star γ Persei are right ascension 3h 03m, declination +53°; the coordinates of the star ρ Persei are right ascension 3h 03m, declination +39°. Measured along the shortest angle in the sky between the two stars, γ Persei is:

The tilt of Earth's spin axis to the direction perpendicular to the ecliptic plane (known as the ecliptic pole) is:

The declination of Polaris, the North Star, when viewed from a location 35° north of the equator, is:

At a certain time the star straight overhead has a right ascension of 2 hours and 30 minutes. One hour later this same star will have a right ascension of:

Over what range of declination will stars be circumpolar (i.e., be visible at any time of the night on any night of the year) for an observer at 30° north latitude?

The celestial coordinates of the star ζ Leonis are right ascension 10h 16m, declination +24°; the coordinates of the star λ Ursae Majoris are right ascension 10h 16m, declination +43°. Measured along the shortest angle in the sky between the two stars, ζ Leonis is:

In its motion across the sky against the background stars in the course of a month, the Moon appears to move about:

To navigators in the northern hemisphere, their latitude in degrees is equal to:

The Moon's equatorial plane is nearly the same as:

What is the right ascension of the Sun?

Sirius is the brightest star in the night sky. You watch it set behind the western horizon about 2 A.M. in the middle of February. About what time will it set in the middle of March?

Astronomy and the Universe

Eclipses and the Motion of the Moon

Gravitation and the Waltz of the Planets

The Nature of Light

Optics and Telescopes

Comparative Planetology I: Our Solar System

Comparative Planetology II: the Origin of Our Solar System

The Living Earth

Our Barren Moon

Mercury, Venus, and Mars: Terrestrial, yet Unique

Jupiter and Saturn: Lords of the Planets

Jupiter and Saturns Satellites of Fire and Ice

Uranus, Neptune, Pluto, and the Kuiper Belt: Remote Worlds

Asteroids, Comets, and Impacts

Our Star, the Sun

The Nature of the Stars

The Birth of Stars

Stellar Evolution: on and After the Main Sequence

Stellar Evolution: The Death of Stars

Stellar Remnants: Neutron Stars and Black Holes

Our Galaxy

Galaxies

Quasars and Active Galaxies

Cosmology: The Origin and Evolution of the Universe

Exploring the Early Universe

The Search for Extraterrestrial Life

Filters

Cygnus appears high in the sky at midnight in July. Andromeda appears high in the sky at midnight in September. (See Figure 2-5 of Universe, 11th ed.) Where is Andromeda at midnight in July?

The celestial coordinates of the star γ Persei are right ascension 3^h 03^m, declination +53°; the coordinates of the star ρ Persei are right ascension 3^h 03^m, declination +39°. Measured along the shortest angle in the sky between the two stars, γ Persei is:

The celestial coordinates of the star ζ Leonis are right ascension 10^h 16^m, declination +24°; the coordinates of the star λ Ursae Majoris are right ascension 10^h 16^m, declination +43°. Measured along the shortest angle in the sky between the two stars, ζ Leonis is: