2 4 In the sky, declination is measured in degrees north or south of the celestial equator.. 9 10 A star with a right ascension of 2.6 hrs will rise 2.6 hours after the vernal equinox..
Trang 1TRUE/FALSE Write 'T' if the statement is true and 'F' if the statement is false.
1) Right ascension in the sky is very similar to latitude on the Earth 1) 2) Latitude and right ascension are coordinate systems used to find objects on the celestial sphere 2)
4) In the sky, declination is measured in degrees north or south of the celestial equator 4) 5) The south celestial pole is located at a declination of -90 degrees 5) 6) In general, the brightest star in a given constellation is designated as alpha 6) 7) Constellations are close clusters of stars, all at about the same distance from the Sun 7) 8) The closest terrestrial analog to hours of right ascension is angle of longitude 8) 9) Over 20,000 stars are visible to the naked eye on the darkest, clearest nights 9) 10) A star with a right ascension of 2.6 hrs will rise 2.6 hours after the vernal equinox 10)
12) The sidereal day is determined by the Earth's rotation with respect to the stars 12) 13) The vernal equinox marks the beginning of spring in the northern hemisphere 13)
15) An hour of right ascension corresponds to 60 degrees in the sky 15) 16) From Earth, the Sun and Moon have about the same angular diameter 16) 17) At the solstices, the Sun's declination will be 23.5 degrees from the equator 17) 18) At the equinoxes, the declination of the Sun must be zero degrees 18)
19) As it orbits the Earth, the Moon appears to move its own diameter (0.5 degrees) eastward every
hour against the background stars
19)
Trang 222) If we are the Moon's penumbra, then we will see a partial lunar eclipse 22)
24) Eighteen days past new moon, the Moon's phase is waning gibbous 24)
25) A total solar eclipse will only occur when the new moon is both on the ecliptic and at its greatest
distance from Earth
25)
29) In the scientific method, it is not necessary to test your theory 29)
MULTIPLE CHOICE Choose the one alternative that best completes the statement or answers the question.
30) Drawing on Eratosthenes' method, if two observers are due north and south of each other and are separated by 400 km, what is the circumference of their spherical world if they see the same star on their meridian at altitudes of 23 degrees and 47 degrees respectively, and at the exact same time?
30)
31) The star Wolf 1061 has a parallax of 2.34 arc seconds, while the star Ross 652 has a parallax of 1.70 arc seconds What can you correctly conclude?
A) Wolf 1061 must have a larger proper motion than Ross 652
B) Ross 652 is closer to Earth than Wolf 1061
C) Wolf 1061 is closer to Earth than Ross 652
D) Ross 652 must have a larger proper motion than Wolf 1061
E) Both stars are outside the Milky Way galaxy
31)
32) The greatest distance above or below the ecliptic the Moon can move is
A) 5.2 degrees
B) 23.5 degrees
C) 27.3 degrees
D) 29.5 degrees
E) 30 degrees
32)
33) In an annular eclipse,
A) the Moon appears as a thin, bright ring
B) the Sun is partially blocked by the Earth
C) the Moon is totally blocked by the Earth
D) the Sun appears as a thin, bright ring
E) the Sun is totally blocked by the Moon
33)
Trang 334) If you are in the Earth's umbra on the Earth's surface, then
A) the Sun is always visible
B) the Moon is always visible
C) it must be a total solar eclipse
D) it must be a lunar eclipse of some type
E) it is night time
34)
35) The synodic month is
A) 29.5 days
B) the basis of the year we use in our modern calendar
C) about two days shorter than the sidereal month
D) based on the Moon's position relative to the stars
E) caused by both the Earth's and Moon's rotations
35)
36) If the Moon appears half lit, and is almost overhead about 6:00 AM, its phase is
A) waning crescent
B) first quarter
C) waxing crescent
D) third quarter
E) full
36)
37) If new moon fell on March 2nd, what is the Moon's phase on March 14th?
A) first quarter B) waning crescent C) waxing gibbous D) full
E) waxing crescent
37)
38) A solar eclipse can only happen during a
A) new moon
B) solstice
C) perihelion passage of the Sun
D) first quarter moon
E) full moon
38)
39) What will occur when the full moon is on the ecliptic?
A) a partial solar eclipse B) a total lunar eclipse C) a partial lunar eclipse if the Moon is at perigee D) an annular lunar eclipse
E) a total solar eclipse
39)
40) If you are in the Moon's umbral shadow, then you are witnessing
A) nighttime
B) some kind of lunar eclipse
C) a total lunar eclipse
D) a partial solar eclipse
E) a total solar eclipse
40)
Trang 441) The time for the Moon to orbit Earth, relative to the stars is
A) 23 hours, 56 minutes
B) about 7 days
C) 27.3 days
D) 29.5 days
E) 18 years, 11.3 days
41)
42) The interval from new Moon to first quarter is about a(n)
42)
43) The star Thuban in Draco
A) lies as the center of the precession cycle
B) is used to locate the vernal equinox
C) was an excellent north pole star in 3,000 BC
D) is brighter than Polaris
E) lies halfway between the bowls of the Big and Little Dippers
43)
44) If Scorpius is now prominent in the summer sky, in 13,000 years it will be best seen
A) in the winter sky
B) in the spring sky
C) in the autumn
D) at the same season; the heavens do not change
E) It will not be visible then at all All of its stars will have vanished by then
44)
45) If Taurus is now rising at sunset, which constellation will rise at sunset next month?
45)
46) The fact that the Earth has moved along its orbit in the time it took to rotate once is the reason for
A) precession
B) the position of the Celestial Equator
C) seasons
D) the difference between solar and sidereal time
E) Earth's 23.5-degree tilt
46)
47) When the Moon is directly opposite the Sun in the sky, its phase is
A) first or third quarter
B) waxing or waning gibbous
C) waxing or waning crescent
D) full
E) new
47)
48) You note that a particular star is directly overhead It will be directly overhead again in
A) 1 hour
B) 12 hours
C) 23 hours 56 minutes
D) 24 hours
E) 24 hours 4 minutes
48)
Trang 549) As you watch a star, you see it move 15 degrees across the sky How long have you been watching it?
A) 15 seconds B) 1 hour C) 15 minutes D) 1 minute E) 3 hours
49)
50) That Polaris will not always be the pole star is due to
A) the Earth's revolution being slightly less than exactly 365.25 days
B) the Moon following the ecliptic, instead of the equator
C) precession shifting the celestial pole
D) the sidereal day being shorter than the solar day
E) the Solar winds blowing the Earth farther away from the Sun
50)
51) From the horizon to the observer's zenith is an angle of
A) 90 degrees for everyone on the Earth
B) 0.0 degrees for an observer at the Earth's north pole
C) 66.5 degrees for everyone on the Earth
D) 30 degrees for observers at a latitude of 30 degrees north
E) 23.5 degrees for observers at the Tropics of Cancer and Capricorn
51)
Trang 652) This diagram explains
A) the reason for the solstices
B) the difference between solar time and sidereal time
C) precession
D) the sidereal day's relation to the seasons
E) the solar day's relation to the Moon
52)
53) The 26,000 year cycle that changes the poles and equinoxes is called
A) regression
B) the Earth's rotation
C) revolution
D) a retrograde loop
E) precession
53)
Trang 754) The twelve constellations the solar system bodies move through are the
A) signs of the zodiac
B) stages of heaven
C) nodes of the ecliptic
D) galactic equator
E) equatorial constellations
54)
55) A star with a right ascension of 1.0 hours will rise
A) 13.0 hours before the vernal equinox
B) 1.0 hours after the vernal equinox
C) 1.0 hours before the vernal equinox
D) at the same time as the vernal equinox
E) 11.0 hours after the vernal equinox
55)
56) What are constellations?
A) groups of stars making an apparent pattern in the celestial sphere B) apparent groupings of stars and planets visible on a given evening C) groups of stars gravitationally bound and appearing close together in the sky D) groups of galaxies gravitationally bound and close together in the sky E) ancient story boards, useless to modern astronomers
56)
57) A star with a declination of +60.0 degrees will be
A) east of the vernal equinox
B) west of the vernal equinox
C) south of the celestial equator
D) north of the celestial equator
E) None of these answers is correct
57)
58) Into how many constellations is the celestial sphere divided?
58)
59) In general, what is true of the alpha star in a constellation?
A) It is the westernmost star in the constellation
B) It is the reddest star in the constellation
C) It is the easternmost star in the constellation
D) It is the star that is closest to Earth
E) It is the brightest star in the constellation
59)
60) If the Moon rises at sunset, then its phase must be
A) full
B) waxing crescent
C) new
D) third quarter
E) waning gibbous
60)
Trang 861) If the Moon is on the ecliptic, new, and at its farthest distance from Earth, we will get a(n) eclipse
A) partial solar B) annular solar C) total solar D) annual lunar E) total lunar
61)
62) Over the course of the year, the Sun's noon altitude varies by degrees
62)
63) If one star has a parallax ten times larger than another's, the first star is than the second
63)
SHORT ANSWER Write the word or phrase that best completes each statement or answers the question.
64) Like latitude on Earth, in the sky is measured in degrees north and south of the
equator
64)
65) The twelve constellations through which the Sun passes are signs of the 65)
66) The time interval of 365.242 days is defined as the 66)
67) The time for the Moon to orbit the Earth, relative to the distant stars is the 67)
68) The apparent annual path the Sun takes through the sky is called the 68)
69) Our seasons are a consequence of the Earth's 23.5 degree 69)
70) That we do not get eclipses every new and full Moon is due to the degree tilt of
the Moon's orbit, relative to the ecliptic
70)
71) The apparent angular shift of any object across a distant background, when viewed from
two different places, is called shift
71)
72) Sirius has a parallax of 0.38", while Alpha Centauri's is 0.77." Alpha Centauri is about
as Sirius
72)
73) If two observatories on opposite sides of the Earth were to measure the position of a star to
calculate its parallax, then the diameter of the Earth would be the
73)
74) One of the requirements of the Scientific Method is that an experiment must be 74)
75) What do both latitude on Earth and declination in the sky measure? 75)
Trang 977) What are the minimum and maximum values for declination in the sky for both north and
south?
77)
78) How are right ascension in the sky and longitude on Earth different? 78)
80) What are the minimum and maximum values for right ascension in the sky? 80)
82) At the solstice, what is the maximum angle the Sun can be above or below the equator? 82)
84) If intending to teach his students the constellations by season, why would an astronomy
instructor be advised to always assign the stars in the current western sky at the beginning
of each term?
84)
85) Which star shows the least motion in the northern sky over the course of an hour? 85) 86) Pensacola, Florida lies at a latitude of 30 degrees north Where is Polaris in its sky? 86) 87) How far above or below the equator can the Sun appear to move? Why? 87) 88) What happens on or about March 20th, and what does the name signify? 88)
90) What is the length of the sidereal month, and how is it determined? 90) 91) How long does the synodic month take, and how it this observed? 91) 92) How far above and below the celestial equator can the Sun move? 92)
93) The first quarter moon rises about noon today; what will its phase be, and when will it rise
tomorrow?
93)
94) The last quarter moon rises tonight about midnight; when will it rise, and what will its
phase be tomorrow night?
94)
95) If the Moon rises exactly at sunset, what will its phase be? Why? 95)
Trang 1097) If Sirius transits my local meridian tonight at 6:43 PM, when will it transit tomorrow? 97)
98) Compare and contrast latitude and declination How does each relate to your position on
Earth?
98)
100) Compare hours of right ascension to time zones on the Earth 100)
101) The Sun and stars rise in the east, and set in the west Contrast ancient and modern
explanations for this observation
101)
103) Why can many more people witness a total lunar eclipse than a total solar eclipse? 103)
106) Describe how Eratosthenes measured the circumference of our planet 106)
108) We get a new and full moon every month Why don't we get two eclipses every month? 108)
Trang 11Answer Key
Testname: UNTITLED1
1) FALSE
2) FALSE
3) TRUE
4) TRUE
5) TRUE
6) TRUE
7) FALSE
8) TRUE
9) FALSE
10) TRUE
11) FALSE
12) TRUE
13) TRUE
14) TRUE
15) FALSE
16) TRUE
17) TRUE
18) TRUE
19) TRUE
20) TRUE
21) TRUE
22) FALSE
23) FALSE
24) TRUE
25) FALSE
26) TRUE
27) TRUE
28) TRUE
29) FALSE
30) C
31) C
32) A
33) D
34) E
35) A
36) D
37) C
38) A
39) B
40) E
41) C
42) C
43) C
44) A
45) E
46) D
Trang 12Answer Key
Testname: UNTITLED1
51) A
52) B
53) E
54) A
55) B
56) A
57) D
58) D
59) E
60) A
61) B
62) C
63) D
64) declination
65) zodiac
66) tropical year
67) sidereal month
68) ecliptic
69) axial tilt
70) 5.2 (or just 5)
71) parallax or parallactic
72) twice as close, or half as far
73) baseline
74) repeatable
75) Angular distance in degrees above or below the geographical and celestial equators
76) Both measure positions east or west from a fixed point; Greenwich on Earth, the vernal equinox in the sky
77) From the equator at 0 degrees, to +90 degrees for the north celestial pole, and down to -90 degrees for the south celestial pole
78) Right ascension is measured in units of time eastward from the vernal equinox, while longitude is measured in degrees east or west of the Greenwich meridian
79) An imaginary hollow sphere, with Earth at its center, on which all the stars (and other celestial bodies) are fixed As the sphere rotates around the Earth, the stars move across our sky
80) From 0 to 24 hours, going eastward from the vernal equinox
81) The solar day is approximately four minutes longer than the sidereal day
82) +23.5 degrees in summer and -23.5 degrees in winter
83) The Sun follows the ecliptic eastward across the sky, never leaving it
84) As the Earth revolves around the Sun, the Sun appears to move one degree eastward per day These stars are,
therefore, soon lost in the Sun's glare
85) Polaris, the North Star, lies within a degree of the celestial pole, and does not move noticeably with the naked eye over
an entire night
86) 30 degrees high in the north
87) The Earth's axial tilt means the Sun's declination can reach 23.5 degrees north or south of the equator at the solstices 88) The vernal equinox, because the days and nights are approximately equal in length
89) The Moon's orbit is not a perfect circle When the Moon is closer to Earth, it is big enough to cover the Sun completely; when it is too far away it appears smaller, so a ring of sunlight is still seen
90) It takes 27.3 days for the Moon to revolve around us and return to the same position against the background of stars 91) The phase cycle of the Moon takes 29.5 days to return to exactly the same phase
92) The Sun never appears more than 23.5 degrees above or the below the celestial equator