Lesson 2

Question 1

Which of the following best describes the modern definition of a constellation?

Answer 1

a region of the celestial sphere

Question 2

Which of the following statements about the celestial equator is true at all latitudes?

Answer 2

It represents an extension of Earth’s equator onto the celestial sphere.

Question 3

Which of the following correctly describes the meridian in your sky?

Answer 3

a half-circle extending from your horizon due north, through your zenith, to your horizon due south

Question 4

If it is midnight in New York, it is

Answer 4

daytime in Sydney, Australia.

Question 5

By locating the north celestial pole (NCP) in the sky, how can you determine your latitude?

Answer 5

The altitude of the NCP is the same as your latitude.

Question 6

Why do we have seasons on Earth

Answer 6

As Earth goes around the Sun and Earth’s axis remains pointed toward Polaris, the Northern and Southern hemispheres alternately receive more and less direct sunlight.

Question 7

When someone on Earth observes the Moon in the first-quarter phase, someone on the Moon facing Earth observes Earth in the

Answer 7

third-quarter Earth phase

Question 8

If the Moon is setting at 6 A.M., the phase of the Moon must be

Answer 8

full

Question 9

If the Moon is setting at noon, the phase of the Moon must be

Answer 9

third quarter

Question 10

If the Moon is rising at midnight, the phase of the Moon must be

Answer 10

third quarter.

Question 11

At approximately what time would a full Moon be on your meridian

Answer 11

midnight

Question 12

In which direction does a quarter Moon rise?

Answer 12

east

Question 13

Ashen light (or earthshine) is

Answer 13

sunlight reflected by Earth that illuminates the “dark” portion of the Moon.

Question 14

All of the following statements are true. Which one explains the reason why there is not a solar eclipse at every new Moon?

Answer 14

The orbital plane of the Moon is tilted by about 5° to the ecliptic plane.

Question 15

What conditions are required for a solar eclipse?

Answer 15

The phase of the Moon must be new, and the nodes of the Moon’s orbit must be nearly aligned with Earth and the Sun.

Question 16

What conditions are required for a lunar eclipse?

Answer 16

The phase of the Moon must be full, and the nodes of the Moon’s orbit must be nearly aligned with Earth and the Sun.

Question 17

In addition to the conditions required for any solar eclipse, what must also be true in order for you to observe a total solar eclipse?

Answer 17

The Moon’s umbra must touch the area where you are located

Question 18

If the Moon is relatively far from Earth, so that the umbra does not reach Earth, someone directly behind the umbra will see

Answer 18

an annular eclipse

Question 19

What happens during the apparent retrograde motion of a planet?

Answer 19

The planet appears to move westward with respect to the stars over a period of many nights.

Question 20

The point directly over your head is called

Answer 20

the zenith

Question 21

An angle of 1 arcsecond is

Answer 21

less than the thickness of a human hair held at arm’s length

Question 22

Suppose you use the Southern Cross to determine that the south celestial pole appears 40 degrees above your horizon. Then you must be located at

Answer 22

latitude 40 degrees south.

Question 23

Suppose you are facing north and you see the Big Dipper close to your northern horizon, with Polaris (and the Little Dipper) above it. Where will you see the Big Dipper in six hours?

Answer 23

to the right of Polaris; that is, 90 degrees counterclockwise from its current position

Question 24

It’s 6 A.M. and the Moon is at its highest point in your sky (crossing the meridian). What is the Moon’s phase?

Answer 24

third quarter