Assignments 1-2

Question 1

Imagine that we put a raisin cake into the oven, with each raisin separated from the others by 1 cm. An hour later, we take it out and the distances between raisins are 3 cm. If you lived in one of the raisins and watched the other raisins as the cake expanded, which of the following would you conclude?

a. All raisins would be moving away from you at the same speed
b. It depends: If you lived in a raisin near the left side of the cake, you’d see other raisins moving away from you, but they’d be coming toward you if you lived in a raisin near the right side of the cake.
c. More distant raisins would be moving away from you faster.
d. More distant raisins would be moving away from you more slowly.

Answer 1

c. More distant raisins would be moving away from you faster.

Question 2

What does the solar system contain?

a. The sun, its planets, and some smaller bodies
b. The sun, galaxies, planets, and stars
c. The sun, galaxy, moons, and stars
d. The sun, galaxy, asteroids, and galaxies

Answer 2

a. The sun, its planets, and some smaller bodies

Question 3

Sirius the brightest star in the sky is about 9 ly way. If the speed of light became half of its present value, how far would Sirius be?

a) 9 ly
b) 18 ly
c) 4.5 ly
d) 2 ly

Answer 3

b) 18 ly

Question 4

Approximately how many times larger than the diameter of a typical planet (the Earth) is the diameter of a typical star (the sun)?

a) 10 times
b) 100 times
c) 1000 times
d) 10,000 times

Answer 4

b) 100 times

Question 5

5. What do we mean when we say that the universe is expanding?

a) Individual galaxies are gradually growing in size.
b) The statement is not meant to be literal; rather, it means that our knowledge of the universe is growing.
c) Average distances are increasing between star systems within galaxies.
d) Average distances are increasing between galaxies.

Answer 5

d) Average distances are increasing between galaxies.

Question 6

Approximately 100 earths would fit inside Jupiter. This Jupiter’s radius must be _______ times larger than Earth’s radius.

a) 100
b) 12
c) 10
d) 1000

Answer 6

c) 10

Question 7

The nearest star to our solar system is alpha centauri at 4.01016m. The diameter of the sun is 1.2109m. How many suns would it take to line up adjacent to each other in order to reach alpha Centauri?

a) 5.6106
b) 5.6106
c) 2.81025
d) 2.810^7

Answer 7

d) 2.8*10^7

Question 8

A spherical particle in the ring of Saturn has radius of about 1m. The surface area of the particle in the area of radiation flow is:

a) 125m2
b) 3.14m2
c) 12.6m2
d) 14m2

Answer 8

c) 12.6m2

Question 9

There are approximately 100 billion stars in our galaxy. If there 100 billion observable galaxies in our universe, what is a reasonable estimate for the total number in the universe?

a) 1.01022
b) 2.01020
c) 1.51015
d) 1.01024

Answer 9

a) 1.0*10^22

Question 10

Which of the following sequences objects ins in the correct order of increasing distance?

a) Venus, saturn, Moon, Andromeda galaxy, Polaris
b) Moon, Venus, Saturn, Polaris, Andromeda galaxy
c) Polaris, Andromeda galaxy, moon, saturn, venus
d) Andromeda galaxy, Saturn, Venus, Polaris, Moon

Answer 10

b) Moon, Venus, Saturn, Polaris, Andromeda galaxy

Question 11

The Andromeda galaxy is about 2,000,000 ly away. Therefore, light started its travel:

a) 1,000,000 y
b) 2,000,000y
c) Just a second ago
d) Can’t be determined

Answer 11

b) 2,000,000y

Question 12

Which of the following statements best describes the Sun?

a) generates energy by nuclear fusion
b) located 10 AU from Earth
c) orbiting the solar system
d) located in the centre of the Milky Way

Answer 12

a) generates energy by nuclear fusion

Question 13

Which of the following is smallest?

a) size of a typical planet
b) 1 AU
c) 1 light-second
d) size of a typical star

Answer 13

a) size of a typical planet

Question 14

One light-hour is the distance that light travels in an hour. How far is this, in kilometers? (Recall that the speed of light is 300,000 km/s.)

a) 1.08 billion km
b) 300,000 km
c) 18 million km
d) 100 million km

Answer 14

a) 1.08 billion km

Question 15

A spherical particle in the ring of Saturn has radius of about 1m. The cross sectional area of the particle in the area of radiation flow is:

a) 125m2
b) 3.14m2
c) 12.6m2
d) 14m2

Answer 15

b) 3.14m2

Question 16

If the landing lights in Denver airport were switched on, then in one second these photons travel to:

a) New York (1580km)
b) Alpha Centauri (40,000,000,000,000 km)
c) The sun (150,000,000 km)
d) Moon (384,000 km)

Answer 16

d) Moon (384,000 km)

Question 17

The age of the universe is?

a) between 10 and 16 million years
b) between 100 million and 160 million
c) between 1 billion and 1.6 billion
d) between 10 billion and 16 billion

Answer 17

d) between 10 billion and 16 billion

Question 18

What is 5.7*10^7 the same as?

a) 5.7 milllion
b) 57 thousand
c) 570 thousand
d) 57 million

Answer 18

b) 57 thousand

Question 19

What is the approximate diameter of the Earth?

a) 1 AU
b) 13,000 light years
c) 13,000 kilometres
d) 1,000,000 kilometers

Answer 19

c) 13,000 kilometres

Question 20

Which of the following is largest?

a) 100 Mpc
b) 10 Kpc
c) 120 Ly
d) 10 AU

Answer 20

a) 100 Mpc

Question 21

If the distance from the sun to the earth is represented y roughly 15 meters, then what would the distance from the Earth to the Moon on the same scale be?

a) about 30 meters
b) about 10 meters
c) about 1 meter
d) smaller than the width of your hand

Answer 21

d) smaller than the width of your hand

Question 22

In the organization diagram below in which area the term: Polaris would appropriate fit?

Answer 22

a) Red area=Milky Way

Question 23

If we use 1 millimeter to represent 1 light-year, how large in diameter is the milky way?

a) 100 millimeters
b) 100 meters
c) 1 kilometer
d) 100 kilometers

Answer 23

b) 100 meters

Question 24

Which of the following is no longer considered a major planet?

a) mercury
b) uranus
c) pluto
d) Saturn

Answer 24

c) pluto

Question 25

You are standing on Earth's equator. Which way is Polaris, the North star? a) 30 degrees up, due West b) on the northern horizon c) directly overhead d) The answer depends on whether it's winter or summer.

Answer 25

b) on the northern horizon

Question 26

By locating the north celestial pole (NCP) in the sky, how can you determine your latitude? a) The altitude of the NCP is the same as your latitude. b) The altitude of the NCP is your angular distance from the North Pole. c) The azimuth of the NCP is the same as your latitude. d) The azimuth of the NCP is the angular distance from the North Pole.

Answer 26

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

Question 27

Orion is visible on winter evenings in the northern hemisphere but not summer evenings because of a) interference from the full Moon. b) the tilt of Earth's axis. c) the location of Earth in its orbit. d) the precession of Earth's axis.

Answer 27

c) the location of Earth in its orbit.

Question 28

Why do we have seasons on Earth? a) 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. b) The tilt of Earth's axis constantly changes between 0 and 23 1/2°, giving us summer when Earth is tilted more and winter when it is straight up. c) Earth's distance from the Sun varies, so that it is summer when we are closer to the Sun and winter when we are farther from the Sun. d) Seasons are caused by the influence of the planet Jupiter on our orbit.

Answer 28

a) 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 29

Which of the following statements is true? a) Both the Northern and Southern hemispheres receive the same amount of sunlight on the equinoxes. b) Both the Northern and Southern hemispheres receive the same amount of sunlight on the solstices. c) The Northern Hemisphere receives the most direct sunlight on the summer solstice. d) Both A and C are true.

Answer 29

d) Both A and C are true.

Question 30

Why is it summer in the Northern Hemisphere when it is winter in the Southern Hemisphere? a) The Northern Hemisphere is closer to the Sun than the Southern Hemisphere. b) The Northern Hemisphere is "on top" of Earth and therefore receives more sunlight. c) The Northern Hemisphere is tilted toward the Sun and receives more direct sunlight. d) The Northern Hemisphere is tilted away from the Sun and receives more indirect sunlight.

Answer 30

c) The Northern Hemisphere is tilted toward the Sun and receives more direct sunlight.

Question 31

Which of the following statements about constellations is false? a) There are only 88 official constellations. b) Some constellations can be seen from both the Northern and Southern hemispheres. c) Some constellations can be seen in both the winter and summer. d) Most constellations will be unrecognizable hundreds of years from now

Answer 31

d) Most constellations will be unrecognizable hundreds of years from now

Question 32

Star Name Apparent Visual Magnitude δ Dra 3.07 α Cet 2.53 Nim 8.07 α CMa -1.46 Refer to Table 2-1. Which star in the table would appear brightest to an observer on Earth? Question options: a) δ Dra b) α Cet c) Nim d) α CMa

Answer 32

d) α CMa

Question 33

What causes the precession of the Earth's rotation axis? a) the force of gravity from the Sun and Moon on the Earth's equatorial bulge b) the force of gravity from the Sun and Jupiter on the Earth-Moon system c) the magnetic field of the Earth d) the impacts of asteroids

Answer 33

a) the force of gravity from the Sun and Moon on the Earth's equatorial bulge

Question 34

If the Earth turns one full rotation in approximately 24 hours, how many degrees per hour does the sky turn? a) 12 deg/h b) 16 deg/h c) 15 deg/h d) 8 deg/h

Answer 34

c) 15 deg/h

Question 35

An observer in Salt Lake City Utah (latitude= 40.7608 N) sees three stars rising in the eastern horizon. Which of these stars might later on pass through zenith point? A* B C

Answer 35

A*

Question 36

Where is an observer's nadir? a) the east point on the observer's horizon b) the north point on the observer's horizon c) the point directly opposite the observer's zenith d) the point directly opposite the north celestial pole

Answer 36

c) the point directly opposite the observer's zenith

Question 37

Which of the following is equivalent to one-3,600th of a degree? a) precession b) second of arc c) minute of arc d) angular diameter

Answer 37

b) second of arc

Question 38

Where is the zenith for an observer standing at a point on the Earth's equator? a) directly overhead b) near the horizon and towards the south c) near the horizon and towards the west d) the position depends on the time of day

Answer 38

a) directly overhead

Question 39

The orbit of the Earth had an eccentricity 0.017. If the eccentricity increased to 0.65 what would happened to the Earth's seasons? e=0.017 e=0.65 a) More intense seasons b) Less intense seasons c) No appreciable change

Answer 39

a) More intense seasons

Question 40

Which of the following locations are closer to the South Celestial Pole ? a) (RA= 14h Declination=+88°) b) (RA= 14h Declination=-88°) c) (RA= 23h Declination=2°) d) (RA= 18h Declination=-66°)

Answer 40

b) (RA= 14h Declination=-88°)

Question 41

Where is the north celestial pole in our sky for latitudes between 35-45° N? a) The answer will vary with latitude in the latitude range 40°-90° N b) The answer will vary with latitude in the latitude range 30°-90° N c) The answer will vary with latitude in the latitude range 35°-40° N d) The answer will vary with latitude in the latitude range 35°-45° N

Answer 41

d) The answer will vary with latitude in the latitude range 35°-45° N

Question 42

18. How often is the sun at zenith for an observer at the equator? a) Never b) Twice per year c) 12 times per year d) Every day

Answer 42

d) Every day

Question 43

Suppose Earth's axis tilt was significantly greater than its current 23.5 degrees, but Earth's rotation period and orbital period were unchanged. Which statement below would not be true? a) Summers and winters would be more severe (for example, hotter and colder, respectively) than they are now. b) The region of Earth where the Sun does not rise on the winter solstice would be larger (extending farther south) than it is now. c) The length of each season (for example, the number of days from the summer solstice to the fall equinox) would be significantly longer than it is now. d) Polaris would not be our North star.

Answer 43

c) The length of each season (for example, the number of days from the summer solstice to the fall equinox) would be significantly longer than it is now.

Question 44

An observer in the northern hemisphere watches the sky for several hours. Due to the motion of the Earth, this observer notices that the stars near the north celestial pole appear to move. What pattern does this apparent movement follow? a) clockwise around the celestial pole b) counter-clockwise around the celestial pole c) from left to right d) from right to left

Answer 44

b) counter-clockwise around the celestial pole

Question 45

If the apparent visual magnitude of a star is 7.3, what does this tell us about the brightness of the star? a) It is one of the brighter stars in the sky. b) It is bright enough that it would be visible even during the day. c) It is not visible with the unaided eye. d) It appears faint because of its great distance from the Earth.

Answer 45

c) It is not visible with the unaided eye.

Question 46

Which of the following describes a concept very similar to latitude? a) right ascension b) declination c) magnitude d) meridian

Answer 46

b) declination

Question 47

Which of the following best defines the ecliptic? a) the plane that is perpendicular to the Earth's axis of rotation b) the projection of the Earth's equator onto the sky c) the path traced out by the Moon in our sky in one month against the background stars d) the path traced out by the Sun in our sky over one year against the background stars

Answer 47

d) the path traced out by the Sun in our sky over one year against the background stars

Question 48

If the north celestial pole appears on your horizon, what is your latitude? a) 50° N b) 50° S c) 90° N d) 0° S

Answer 48

d) 0° S

Question 49

If the north celestial pole appears on your zenith, what is your latitude? a) 50° N b) 50° S c) 90° N d) 0° S

Answer 49

c) 90° N

Question 50

Where on Earth would you be if Polaris were at your zenith? a) North Pole b) Arctic Circle c) Tropic of Cancer d) Equator

Answer 50

a) North Pole

Question 51

While watching a star, you see it moves 45 degrees across the sky. How long have you been watching it? a) 1 hour b) 3 hours c) 15 minutes d) 15 seconds

Answer 51

b) 3 hours

Question 52

28. An observer in the northern hemisphere takes a time exposure photograph of the night sky. If the illustration depicts the photograph taken by the observer, which direction was the camera pointing? a) Due north b) Due south c) Due east d) Straight up

Answer 52

a) Due north

Question 53

An observer in the northern hemisphere takes a time exposure photograph of the night sky. If the illustration depicts the photograph taken by the observer, which direction was the camera pointing? a) Due north b) Due south c) Due east d) Due west

Answer 53

b) Due south

Question 54

For an observer in Sydney Australia, at a latitude 34° South, what is the angle between the southern horizon and the south celestial pole? a) 23.5° b) 34° c) 45° d) 51°

Answer 54

b) 34°

Question 55

If you were standing at the Earth's North Pole, which of the following would be located at the zenith? a) the nadir b) the star Vega c) the celestial equator d) the north celestial pole

Answer 55

d) the north celestial pole

Question 56

How much of the night sky lies north of the celestial equator? a) Less than half, because of the tilt of the equator to the ecliptic plane. b) More than half, because of the precession of the poles. c) Exactly half. d) All of the night sky.

Answer 56

c) Exactly half.