Chapter 1

Question 1

In the sky, declination is measured in degrees north or south of the celestial equator.

Answer 1

True

Question 2

In reality, the Moon’s orbit about Earth is tilted (by about 5°) with respect to Earth’s orbit about the Sun. As a result, the actual number of solar eclipses that occur each year is approximately _____.

Answer 2

2

Question 3

What conditions must exist for a solar eclipse to occur?

Answer 3

The phase of the Moon must be new and the Moon must be passing through Earth’s orbital plane.

Question 4

What conditions must exist for a lunar eclipse to occur?

Answer 4

The phase of the Moon must be full and the Moon must be passing through Earth’s orbital plane.

Question 5

If you could change the layout of the solar system, which of the following would cause a lunar eclipse to occur at least once every month in this hypothetical situation?

Answer 5

Change the Moon’s orbital plane so it is in the same plane as Earth’s orbit around the Sun.

Question 6

Triangular Distance

Answer 6

1. As the distance of the object increases, parallax decrease
2. As the size of the baseline increases, parallax decreases
3. As the distance to the background objects increase, parallax remains the same

Question 7

Consider the Moon and Sun. Their angular diameters are both equal to about .5 degree. If the Sun is roughly 400 times more distant than the Moon, how much bigger is the Sun’s diameter than the Moon’s?

Answer 7

about 400 times bigger

Question 8

While watching a star, you see it moves 15 degrees across the sky. How long have you been watching it?

Answer 8

1 hour

Question 9

How does the parallax of a nearby object compare to that of an object farther away?

Answer 9

The nearby object exhibits a larger parallax than the farther object.

Question 10

Which of the following is NOT true of the celestial equator?

Answer 10

It traces the path of the Sun among the constellations.

Question 11

The south celestial pole is located at a declination of -90 degrees.

Answer 11

True

Question 12

In the summer we observe different constellations than in the winter. This is because ________.

Answer 12

Earth has moved to the other side of its orbit

Question 13

The closest terrestrial analog to hours of right ascension is angle of longitude.

Answer 13

True

Question 14

A sidereal day is shorter than a solar day because ________.

Answer 14

Earth is moving around the Sun

Question 15

The angular diameter of an object is inversely proportional to its distance from the observer.

Answer 15

True

Question 16

Arrange the following objects in order of increasing size.

Answer 16

Earth, Solar System, Galaxy, Universe

Question 17

Night and day have approximately equal length at what time or times of the year?

Answer 17

Vernal and autumnal equinoxes

Question 18

A solar eclipse can only happen during a:

Answer 18

new moon.

Question 19

How long is the precession cycle?

Answer 19

26,000 years

Question 20

The star Wolf 1061 has a parallax of 2.34 arcseconds, while the star Ross 652 has a parallax of 1.70 arcseconds. What can you correctly conclude?

Answer 20

Wolf 1061 is closer to Earth than Ross 652.

Question 21

What is the cause of the phases of the Moon?

Answer 21

As the Moon orbits the Earth, different parts of the side facing the Earth are illuminated by the Sun.

Question 22

If the Moon rose tonight at 6 PM, then tomorrow it will rise about:

Answer 22

7 PM.

Question 23

At the solstices, the Sun’s declination will be 23.5 degrees from the equator.

Answer 23

True

Question 24

The stars in a constellation are physically close to one another.

Answer 24

False

Question 25

Which of the following describes parallax?

Answer 25

It is inversely proportional to the distance to the star.

Question 26

The constellations are ________.

Answer 26

arbitrary regions that cover the entire sky, which astronomers have named

Question 27

A lunar eclipse can occur only during the full phase.

Answer 27

True

Question 28

The sidereal day is determined by the Earth’s rotation with respect to the stars.

Answer 28

True

Question 29

Where on Earth can you observe all the stars in the sky over an entire year?

Answer 29

Equator

Question 30

Where would you be if the Sun sets for six continuous months, beginning on September 23rd?

Answer 30

North Pole

Question 31

Where on Earth would you be if Polaris was at your zenith?

Answer 31

North Pole

Question 32

The phenomenon known as precession is due to a regular, periodic variation in what property of Earth’s motion?

Answer 32

the direction in which its rotational axis points

Question 33

According to Figure 0.8 in the textbook (The Zodiac), in January the Sun is in the constellation

Answer 33

Aquarius.

Question 34

What is the range of values for Right Ascension?

Answer 34

0 to 23 hours

Question 35

The celestial sphere is divided into 88 modern constellations.

Answer 35

True

Question 36

When the Moon is directly opposite the Sun in the sky, its phase is

Answer 36

full.

Question 37

What physical property of Earth gives rise to the seasons?

Answer 37

The tilt of its rotation axis to the plane of its orbit

Question 38

Latitude and right ascension are coordinate systems used to find objects on the celestial sphere.

Answer 38

False

Question 39

When does the Full Moon rise?

Answer 39

sunset