Exam 1

Question 1

a. When you stand facing North – looking at the North star on a clear night – to which side of you is East?

Answer 1

i. To your right

Question 2

a. Imagine watching the sky and the stars & constellations around the North Star for several hours. Looking to the East you would notice new stars & constellations rising and looking to the West you would see stars & constellations setting. But the North Star… it would remain (very nearly) in the same spot in the sky. The North Star stays put while all other stars & constellations appear to revolve.
With this and your answer to the previous question in mind, how do all the stars & constellations appear to revolve around the North Star over the course of the night: clockwise or counter-clockwise?

Answer 2

i. Counter Clockwise

Question 3

a. About how long does it take for all the stars and constellations in the sky to appear to revolve exactly once around the North star?

Answer 3

i. About 24 hours

Question 4

a. identify six constellations that are circumpolar for us here in West MI, by selecting them in the list below.

Answer 4

o	Ursa major
o	Ursa minor
o	Draco
o	Cepheus
o	Cassiopia
o	Camelopardalis

Question 5

1. Today, do our clocks tell daylight time or standard time?

Answer 5

o Standard Time

Question 6

a. Each month, constellations cross the meridian____ earlier

Answer 6

2 hours earlier

Question 7

• Asterism

Answer 7

o Group of stars

Question 8

• Constellation

Answer 8

o Section of the sky

o 88 constellations in the sky

Question 9

• stars rotate _____ around the north star

Answer 9

Counter clockwise

Question 10

o When the left hand side of the moon is lit, it is a _____

Answer 10

Waining

Question 11

o Full moons occur roughly ____ earlier than the month before

Answer 11

One day

Question 12

How long is the lunar cycle

Answer 12

29.5 days

Question 13

How long is each phase of the moon

Answer 13

3.5 days

Question 14

The moon moves _____ around the sky

Answer 14

Eastward

Question 15

o The moon rises about ___ minutes later each day

Answer 15

50

Question 16

is the moon ever completely overhead

Answer 16

No, always a little south

Question 17

How long is the moon’s sidereal period

Answer 17

27.3 days

Question 18

Moon’s sidereal period

Answer 18

o This is how long it takes the moon to go completely around the sky and come back to the constellation it started in

Question 19

o The line that divides the sky north and south is the ____

Answer 19

Meridian

Question 20

Solar day - sun

Answer 20

meridian crossing to meridian crossing

varies a tiny bit periodically (seconds less, seconds more).

It is what our clocks are synced with (average of 24 hours over the length of the year)

Question 21

Sidereal day - sun

Answer 21

23 hours and 56 minutes and it is the time it takes any star (besides Polaris) to go from meridian to meridian

Question 22

o Compared to a solar day, the stars go around the sky ____ than the sun

Answer 22

Faster

Question 23

How much faster do the stars go around the sky

Answer 23

(4 min faster each day, 30 min a week, 2 hours a month, or 6 hours a season)

Question 24

o A day by the stars is ____ faster than a day by the sun

Answer 24

4 minutes

Question 25

o The sun drifts ____ against the background stars

Answer 25

Eastward

Question 26

o The ____ is the imaginary line that represents the path that the sun traces out over the course of a year

Answer 26

Ecliptic

Question 27

o The ecliptic passes through all of the constellations represented in the ____

Answer 27

Zodiac

Question 28

o List the Zodiac constellations

Answer 28

♣	Leo
♣	Libra
♣	Virgo
♣	Sagittarius
♣	Pisces
♣	Taurus
♣	Cancer
♣	Capricorn
♣	Gemini
♣	Aires
♣	Aquarius
♣	Scorpio
♣	Ophiuchus (the sun just recently started passing through it)

Question 29

Which magnitude is higher, -3 or -2

Answer 29

-3

Question 30

What is the brightest star in the sky and what is its magnitude

Answer 30

Sirrus; 0

Question 31

• Ptolemy

Answer 31

o Greatest contribution to cartography was his latitude and longitude

Question 32

o our latitude and longitude in Grand Rapids is

Answer 32

43 degrees N and 86 degrees W

Question 33

• Average temperature of the sun is ____

Answer 33

6,000 degrees Kelvin

Question 34

How many miles is 1 AU

Answer 34

93,000,000

Question 35

• If a photon of light is created in the core, it takes ____ years for it to travel to the photosphere

Answer 35

1 million

Question 36

• The sun is ___ light minutes away

Answer 36

7-8

Question 37

• Hydrostatic equilibrium

Answer 37

o If the core got hotter, the sun would get bigger and brighter. Due to this increase in size, the sun would eventually shrink back down because the core can’t keep the sun that hot. Vice versa if the sun’s core got cooler
o The sun is nearly perfectly stable due to hydrostatic equilibrium

Question 38

• Nuclear fission

Answer 38

o When a heavier element is split into two smaller elements
o Produces radioactive waste and runoff
o Usually happens at room temperature

Question 39

• Nuclear fusion

Answer 39

o When two lighter elements are combined to make a larger element
o Most stars produce their energy through nuclear fusion
o Called hydrogen burning in astronomy
o In the core, hydrogen is slowly using its hydrogen and turning it into helium
o Only produces helium, nothing radioactive
o Requires very high temperatures, such as in the core of the sun