Astronomy Final Exam: Chapters 1 & 2

Question 1

What does the Universe contain?

Answer 1

Everything (all the galaxies)

Question 2

What is an Astronomical Unit (AU)?

Answer 2

The average distance from Earth to the Sun

Question 3

What is a light year?

Answer 3

The distance light travels in one year

Question 4

What is 1 light year?

Answer 4

63,000 AU

Question 5

What is the order of planets?

Answer 5

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune

Question 6

What are dwarf planets?

Answer 6

Astronomical objects that meet some of the requirements of a planet but not all

Question 7

What is the composition of the Sun?

Answer 7

Made of hydrogen & helium

Question 8

When did our solar system form?

Answer 8

4.6 billion years ago

Question 9

What are star magnitudes?

Answer 9

How bright a star is (energy)

Question 10

What does the 1st star magnitude represent?

Answer 10

The brightest star

Question 11

What does the 6th star magnitude represent?

Answer 11

The dimmest star

Question 12

Why are some star magnitudes negative numbers?

Answer 12

Stars are brighter than the scale because scientific instruments redefined the scale (<1 and >6)

Question 13

What does the magnitude difference of 5 represent?

Answer 13

Flux ratio of 100

Question 14

What does the magnitude difference of 1 represent?

Answer 14

2.51 times brighter (other differences is 2.51 to power of difference)

Question 15

Why do we have seasons?

Answer 15

Due to Earth’s axis tilt of 23.4 degrees

Question 16

Where does the Sun move during the seasons?

Answer 16

The Sun moves to the northern sky in the spring & southern sky in the fall / winter

Question 17

What causes day and night?

Answer 17

Earth’s rotation

Question 18

Dos stars go away during the daytime?

Answer 18

No

Question 19

What is the ecliptic?

Answer 19

The apparent path of the Sun in the sky (westward motion of the sky = eastward rotation of Earth)

Question 20

What is angular distance?

Answer 20

Angles between two lines extending from your eyes to two objects

Question 21

What are angular distance measurements?

Answer 21

Degrees = full circle (360)
Arc Minutes ( ‘ ) = 1 degree = 60’
Arc seconds ( “ ) = 1’=60”