Question 1

Where must you stand on Earth to have the celestial equator pass through your zenith?

Accepted Answer

A) the North Pole 
B) the South Pole 
C) either pole 
D) the equator 
A) the North Pole 
B) the South Pole 
C) either pole 
D) the equator

Question 2

Suppose Earth's rotation axis were straight up and down with respect to the plane of the ecliptic and not tilted. Each of the following statements would be true except one. Which one would not be true?

Accepted Answer

A) The stars would rise along paths perpendicular to the horizon (rather than slanted) when viewed from middle latitudes. 
B) Seasons, as we presently experience them, would not exist. 
C) Every point on Earth would experience 12 hours of sunlight and 12 hours of darkness each day. 
D) In general, the declinations of stars would be different from their present values. 
A) The stars would rise along paths perpendicular to the horizon (rather than slanted) when viewed from middle latitudes. 
B) Seasons, as we presently experience them, would not exist. 
C) Every point on Earth would experience 12 hours of sunlight and 12 hours of darkness each day. 
D) In general, the declinations of stars would be different from their present values.

Question 3

If you view the sky from 20° north of the equator, the north circumpolar stars (which do not rise and set) would be:

Accepted Answer

A) the stars within 20° of the horizon. 
B) the stars within 20° of Polaris, the North Star. 
C) the stars within 20° of the zenith (the point directly overhead). 
D) nonexistent, since all the stars rise and set when viewed from 20° north of the equator. 
A) the stars within 20° of the horizon. 
B) the stars within 20° of Polaris, the North Star. 
C) the stars within 20° of the zenith (the point directly overhead). 
D) nonexistent, since all the stars rise and set when viewed from 20° north of the equator.

Question 4

If a person on the equator sees a particular star cross the horizon at 10 P.M. (2200 hours) on a particular night, what time would the same person (at the same location) see that star cross the horizon on the next night?

Accepted Answer

A) 10:04 P.M. 
B) This star will not rise the next night and will be seen again only after 1 year. 
C) 10:00 P.M. 
D) 9:56 P.M. 
A) 10:04 P.M. 
B) This star will not rise the next night and will be seen again only after 1 year. 
C) 10:00 P.M. 
D) 9:56 P.M.

Question 5

What is the declination of the Sun?

Accepted Answer

A) 0° 
B) 90° 
C) a number that changes only very slowly because of precession 
D) a number that changes significantly over a day 
A) 0° 
B) 90° 
C) a number that changes only very slowly because of precession 
D) a number that changes significantly over a day

Question 6

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 the South Pole?

Accepted Answer

A) 0° to 90°N 
B) only stars at the south celestial pole 
C) 90°S to 90°N (the whole sky) 
D) 0° to 90°S 
A) 0° to 90°N 
B) only stars at the south celestial pole 
C) 90°S to 90°N (the whole sky) 
D) 0° to 90°S

Question 7

If the daytime sky were not bright, in which direction would we see the Sun move along the ecliptic over the course of 1 year, relative to the background stars?

Accepted Answer

A) toward the east 
B) toward the southwest 
C) toward the west 
D) toward the northwest 
A) toward the east 
B) toward the southwest 
C) toward the west 
D) toward the northwest

Question 8

Constellations are generally made up of stars that are:

Accepted Answer

A) moving through space together. 
B) about the same age. 
C) separated by relatively small distances (compared to their distances from us). 
D) merely located along more or less the same line of sight as viewed from Earth. 
A) moving through space together. 
B) about the same age. 
C) separated by relatively small distances (compared to their distances from us). 
D) merely located along more or less the same line of sight as viewed from Earth.

Question 9

At what approximate value of right ascension was the Sun this year on June 21?

Accepted Answer

A) 18 hours 
B) 0 hours 
C) 12 hours 
D) 6 hours 
A) 18 hours 
B) 0 hours 
C) 12 hours 
D) 6 hours

Question 10

At what approximate value of right ascension was the Sun this year on March 21?

Accepted Answer

A) 1 hour 
B) no particular value 
C) 12 hours 
D) 0 hours 
A) 1 hour 
B) no particular value 
C) 12 hours 
D) 0 hours

Question 11

Time, as indicated by an uncorrected sundial, can differ from true time by as much as 15 minutes at certain times of the year. This is because:

Accepted Answer

A) Earth moves non-uniformly along an orbit inclined to the celestial equator. 
B) the Sun moves with respect to the background stars because of our motion on an orbiting Earth. 
C) the time zones are poorly defined on Earth's surface, leading to time errors that vary through the year. 
D) Earth's rotation rate varies throughout the year. 
A) Earth moves non-uniformly along an orbit inclined to the celestial equator. 
B) the Sun moves with respect to the background stars because of our motion on an orbiting Earth. 
C) the time zones are poorly defined on Earth's surface, leading to time errors that vary through the year. 
D) Earth's rotation rate varies throughout the year.

Question 12

Seasonal variations on a planet's surface occur because:

Accepted Answer

A) the planet's distance from the Sun varies periodically over the orbital path. 
B) clouds alternately form and decay away in a periodic way. 
C) the planet's axis of spin is tilted with respect to the perpendicular to the orbital plane. 
D) volcanoes periodically cloud out the atmospheres of planets because of tidal interactions and distortions. 
A) the planet's distance from the Sun varies periodically over the orbital path. 
B) clouds alternately form and decay away in a periodic way. 
C) the planet's axis of spin is tilted with respect to the perpendicular to the orbital plane. 
D) volcanoes periodically cloud out the atmospheres of planets because of tidal interactions and distortions.

Question 13

An observer's meridian passes through:

Accepted Answer

A) his or her zenith and the north and south celestial poles. 
B) his or her zenith and the east and west positions on his or her horizon. 
C) the north and south celestial poles and the vernal equinox position. 
D) his or her zenith and the vernal and autumnal equinoxes. 
A) his or her zenith and the north and south celestial poles. 
B) his or her zenith and the east and west positions on his or her horizon. 
C) the north and south celestial poles and the vernal equinox position. 
D) his or her zenith and the vernal and autumnal equinoxes.

Question 14

If the stars Polaris and Arcturus (as shown in Figure 2-6 of Universe, 11th ed.), are known to be 71° apart, how far away from Polaris is the closest star in Ursa Major?
​
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Accepted Answer

A) about 25° 
B) about 2.5° 
C) about 250° 
D) about 7.1° 
A) about 25° 
B) about 2.5° 
C) about 250° 
D) about 7.1°

Question 15

At which time of the year will your shadow in sunlight at midday be shortest?

Accepted Answer

A) midwinter, or early January 
B) midsummer, about August 5 
C) the first day of summer, about June 21 
D) the first day of spring, about March 21 
A) midwinter, or early January 
B) midsummer, about August 5 
C) the first day of summer, about June 21 
D) the first day of spring, about March 21

Question 16

You view the night sky for a period of 1 hour. What changes during this hour?

Accepted Answer

A) the right ascension of a particular star, like Castor in Gemini 
B) the declination of a particular star, like Pollux in Gemini 
C) the right ascension of the star at your zenith 
D) the position of Polaris 
A) the right ascension of a particular star, like Castor in Gemini 
B) the declination of a particular star, like Pollux in Gemini 
C) the right ascension of the star at your zenith 
D) the position of Polaris

Question 17

A given star in the sky will reach its highest point for a particular observer when it passes through the:

Accepted Answer

A) zodiac. 
B) ecliptic plane. 
C) meridian. 
D) celestial equator. 
A) zodiac. 
B) ecliptic plane. 
C) meridian. 
D) celestial equator.

Question 18

Do the astronomical coordinates of right ascension and declination of a star change systematically night by night?

Accepted Answer

A) They do not change, since they are positions on a fixed star chart. 
B) Yes, because of the motion of Earth in its orbit around the Sun. 
C) Yes, because of the bending of light by Earth's atmosphere. 
D) Yes, because of the precession of Earth's spin axis. 
A) They do not change, since they are positions on a fixed star chart. 
B) Yes, because of the motion of Earth in its orbit around the Sun. 
C) Yes, because of the bending of light by Earth's atmosphere. 
D) Yes, because of the precession of Earth's spin axis.

Question 19

People in which one of the following cities experience sunrise first?

Accepted Answer

A) New York 
B) San Francisco 
C) Chicago 
D) Denver 
A) New York 
B) San Francisco 
C) Chicago 
D) Denver

Exam 2: Knowing the Heavens

Where must you stand on Earth to have the celestial equator pass through your zenith?

Suppose Earth's rotation axis were straight up and down with respect to the plane of the ecliptic and not tilted. Each of the following statements would be true except one. Which one would not be true?

If you view the sky from 20° north of the equator, the north circumpolar stars (which do not rise and set) would be:

If a person on the equator sees a particular star cross the horizon at 10 P.M. (2200 hours) on a particular night, what time would the same person (at the same location) see that star cross the horizon on the next night?

What is the declination of the Sun?

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 the South Pole?

If the daytime sky were not bright, in which direction would we see the Sun move along the ecliptic over the course of 1 year, relative to the background stars?

Constellations are generally made up of stars that are:

At what approximate value of right ascension was the Sun this year on June 21?

At what approximate value of right ascension was the Sun this year on March 21?

Time, as indicated by an uncorrected sundial, can differ from true time by as much as 15 minutes at certain times of the year. This is because:

Seasonal variations on a planet's surface occur because:

An observer's meridian passes through:

If the stars Polaris and Arcturus (as shown in Figure 2-6 of Universe, 11th ed.), are known to be 71° apart, how far away from Polaris is the closest star in Ursa Major? ​ ​

At which time of the year will your shadow in sunlight at midday be shortest?

You view the night sky for a period of 1 hour. What changes during this hour?

A given star in the sky will reach its highest point for a particular observer when it passes through the:

Do the astronomical coordinates of right ascension and declination of a star change systematically night by night?

People in which one of the following cities experience sunrise first?

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

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If the stars Polaris and Arcturus (as shown in Figure 2-6 of Universe, 11th ed.), are known to be 71° apart, how far away from Polaris is the closest star in Ursa Major?