Deck 21: Origin of Modern Astronomy

Question 1

Why do the planets "drift" east relative to the stars and then move west for periods of time?

A)They are moving in separate orbits around the sun as it goes around the earth,producing the periodic backtracking.
B)They are moving in large elliptical orbits,so when observed from Earth,their motion changes depending on whether they are near or far from the sun at a given time.
C)They are moving in the same rotation sense as the earth around the sun,but as the earth moves faster (or slower,depending on the planet)the motion appears to be backwards.
D)They don't move,they stay fixed relative to the stars.

Answer 1

C

Question 2

The earliest astronomical records appear to have been made by the ancient Chinese,Egyptians,and Babylonians in order to ________.

A)predict future positions of celestial objects to identify good or "lucky" dates for various important events
B)determine who should be sacrificed or promoted based on heavenly signs at their birth
C)predict the best dates for traveling,particularly by boat,and where to build temples
D)determine when to plant crops or hunt animals based on seasonal changes

Answer 2

D

Question 3

The true shape of the planetary orbits was discovered by ________.

A)Sir Isaac Newton
B)Galileo
C)Tycho Brahe
D)Nicolaus Copernicus
E)Johannes Kepler

Answer 3

E

Question 4

What is the modern explanation for what the ancient Chinese called "guest stars"?

A)They are comets.
B)They are planets.
C)They are Nova or Supernova.
D)They are meteorites.
E)None of the above.

Question 5

According to the Ptolemaic (Greek)model of the universe,how many "heavenly" bodies could be observed wandering along the background of stars?

A)one
B)two
C)five
D)seven

Question 6

One of the discoveries which led to the modern view of the solar system was that the orbits of the planets are ________.

A)circles
B)ellipses
C)hyperbolas
D)parabolas

Question 7

When viewing the planets,Mars appears to move backwards,or retrograde,because ________.

A)it is rotating around the sun slower than the earth's rotation
B)it is rotating around the sun faster than the earth's rotation
C)it is rotating at approximately the same speed but its orbit is more elliptical than the earth's rotation
D)it is rotating at approximately the same speed but its orbit is more circular than earth's orbit

Question 8

Three laws of planetary motion were discovered by ________.

A)Johannes Kepler
B)Galileo
C)Tycho Brahe
D)Nicolaus Copernicus

Question 9

Why were planets called "wanderers" by early Astronomers?

A)They move in random paths across the sky due to their complex orbits around the Sun.
B)They move relative to the stars.
C)They move relative to the moon because of their orbits around the earth.
D)They move relative to the North Star,but not other stars.

Question 10

This scientist determined the nature of the forces that kept the planets in their orbits.

A)Sir Isaac Newton
B)Galileo
C)Tycho Brahe
D)Nicolaus Copernicus

Question 11

How did the Greeks estimate the size of the earth?

A)They didn't; everyone thought the world was flat until Columbus' time.
B)They measured the angle of the sun above the horizon at midday in two places with different latitude and used the angle to estimate the circumference of the earth.
C)They used the height of sailing ships as they sailed over the horizon to estimate curvature of the earth,which allowed estimation of the size of the earth.
D)They measured the altitude of mountains in Greece,then used the distance they were lost from sight to estimate the curvature of the earth,which allowed estimation of the size of the earth.

Question 12

Galileo observed several features using the telescope.Which one of the following did he not discover?

A)sunspots
B)phases of Venus
C)Jupiter's four largest moons
D)the two moons of Mars

Question 13

What is the modern explanation for "guest stars" that appear in the night sky and then disappear?

A)unusually bright planets produced when they pass closest to earth
B)comets passing close to Earth
C)stars that go Nova or Supernova and appear as bright objects during the event
D)alignments of stars that make them suddenly appear bright

Question 14

The first modern astronomer to propose a Sun-centered universe was ________.

A)Sir Isaac Newton
B)Galileo
C)Tycho Brahe
D)Nicolaus Copernicus

Question 15

In the Ptolemaic (Greek)model of the universe,the ________.

A)earth was flat
B)earth was in the center of the universe
C)Sun was in the center of the solar system
D)earth rotated on its axis to produce night and day

Question 16

In the Ptolemaic (Greek)model of the universe,the stars are attached to the ________.

A)celestial sphere
B)zodiac
C)plane of the ecliptic
D)deferent
E)stadia

Question 17

Planets appear to move ________ each night,but occasionally they appear to stop and reverse direction.

A)northward
B)southward
C)eastward
D)westward
E)It varies significantly.

Question 18

The apparent westward "drift" of the planets compared to the background stars is called ________.

A)Ptolemaic motion
B)occultation
C)precession
D)retrograde motion

Question 19

Who wrote the book entitled Of the Revolutions of Celestial Spheres (De Revolutionibus)?

A)Sir Isaac Newton
B)Galileo
C)Tycho Brahe
D)Nicolaus Copernicus
E)Johannes Kepler

Question 20

This scientist was the first to use the telescope in astronomy.

A)Sir Isaac Newton
B)Galileo
C)Tycho Brahe
D)Nicolaus Copernicus

Question 21

The apparent path of the Sun upon the celestial sphere is called the ________.

A)parallax
B)ecliptic
C)precession
D)declination
E)sidereal

Question 22

Think about the correlation of the celestial coordinate system,the tilt of the earth's axis,and the positions on Earth.If you are an observer in the Southern Hemisphere,2 degrees north of the Tropic of Capricorn,What time of year will you be able to see the North Star?

A)Never; you can never see the North star from the Southern Hemisphere.
B)on the Southern Hemisphere vernal equinox
C)on the Southern Hemisphere summer solstice,around Dec.21
D)at the Northern Hemisphere summer solstice,around June 21

Question 23

This scientist wrote a book entitled Dialogue of the Great World Systems that compared the Earth-centered system with the Sun-centered system.

A)Sir Isaac Newton
B)Galileo
C)Tycho Brahe
D)Nicolaus Copernicus
E)Johannes Kepler

Question 24

Kepler's third law states that the planet's orbital period squared is equal to its mean solar distance cubed.Consequently,the solar distances of the planets can be calculated when their periods of revolution are known.The orbital period of Jupiter is 12 years,what is its distance from the sun in astronomical units?

A)12
B)5)2
C)530
D)16.1

Question 25

The belt of constellations through which all the planets move is called the ________.

A)Planetoid
B)Parallax
C)Cosmos
D)Zodiac
E)Milky Way

Question 26

Alpha Centauri is a famous star because it is one of the closest stars to earth (other than the sun of course).Where would you look in the night sky for Alpha Centauri?

A)RA 15hr 30min; D 56 degrees
B)Look for the second brightest star in the constellation Alpha.
C)Look for Hydra,then to the right for Hercules,and it will be half way between.
D)Look for the brightest star in the constellation Centaurus.

Question 27

The ________ day is the time it takes for Earth to make one complete rotation with respect to a star other than our Sun.

A)equinox
B)sidereal
C)synodic
D)zodiacal
E)Julian

Question 28

Which of these men formulated the Law of Universal Gravitation?

A)Sir Isaac Newton
B)Galileo
C)Tycho Brahe
D)Nicolaus Copernicus
E)Johannes Kepler

Question 29

The planets are "wanderers" in the night sky because they move relative to the stars.However,there movement is limited to the plane of the solar system,which is disk shaped.So relative to the celestial coordinate system,how do the planets actually move across the sky?

A)They move along the celestial equator.
B)The move perpendicular to the celestial equator.
C)The move along the zodiac.
D)They follow wobbling paths related to the precession of equinoxes.

Question 30

What is the right ascension and declination for Polaris,the North Star?

A)RA 0 hr,D 0 degrees
B)RA 0 hr,D 80 degrees
C)RA indeterminate,D 90 degrees
D)RA 90 hr,D -90 degrees

Question 31

A statement you will sometimes hear people say is that a day is not 24 hours but is really 23 hr.56 min.and 4 sec.What does this refer to?

A)The original definition of the hour was off,and with more accurate atomic clocks we now realize the real day is this length.
B)This is sidereal time,not solar time; a solar day is 24 hours.
C)Our clocks drift that much each day,and we average out the affect with period time shifts,like leap years and leap seconds.
D)It is just an urban geek myth; the day really is 24 hours long.

Question 32

Tyco Brahe set out to disprove Copernicus,so why is he famous for developing modern astronomical theory?

A)He made very precise measurements that were key data used by Kepler.
B)He theorized the concept of gravity with no data,which was left undiscovered until Newton.
C)Although he set out to disprove Copernicus,he ultimately accepted Copernicus' theory and was executed by the inquisition.
D)None of these is correct.

Question 33

Astrology is the folklore that arose from watching alignments in the night sky and the belief that these "celestial events" controlled human events.A 1960's folk song,"The Age of Aquarius" has numerous astrology references that relate to the positions of objects in the sky.The song has a line: "When the moon is in the 7th house,and Jupiter aligns with Mars,then peace will guide the planet..." From your knowledge of the stellar constellations and the celestial coordinate system,what does this line mean?

A)When Jupiter and Mars align in the sky,and the moon is in the 7th constellation of the zodiac,then
B)When Jupiter and Mars align with the sun,and it is the 7th full moon of the year,then peace…
C)When the moon crosses the zodiac in the 7th month of the year,and Jupiter and Mars align with the moon,then peace…
D)It is just a nonsense line with no meaning.

Question 34

A very slow motion of Earth's axis that requires 26,000 years to complete is called ________.

A)Ptolemaic motion
B)occultation
C)axial precession
D)perturbation
E)retrograde motion

Question 35

Any variance in the orbit of a planet from its predicted path is referred to as ________.

A)Ptolemaic motion
B)occultation
C)precession
D)perturbation
E)retrograde motion

Question 36

At the beginning of spring,the vernal equinox,what is the right ascension of the sun?

A)0
B)12 hr
C)18 hr
D)90 degrees

Question 37

The Southern Cross is a Southern Hemisphere constellation that is as famous the big dipper in the Northern Hemisphere because of the brightness of the stars.It has a Southern Hemisphere declination slightly higher than the big dipper's Northern Hemisphere declination.Is it visible anywhere in the United States?

A)No,it is not visible anywhere in the U.S.because the entire country is too far north.
B)Yes,it is visible in most of the southern tier of states during summer months.
C)Yes,it is visible during much of the year,but it is obscured by the full moon.
D)Yes,it is visible in Hawaii during the summer months.

Question 38

Where will the North Star be,relative to the celestial coordinates,12,000 years from now?

A)Right where it is now; it isn't going anywhere.
B)Several degrees from the North Pole position,with Vega as the North Star.
C)23 1/2 degrees away from the pole,due to precession.
D)None of these is correct.

Question 39

Why did Galileo's observation that Venus showed phases like the moon indicate that the geocentric theory of the solar system was not possible?

A)It demonstrated that Venus orbited earth like the moon,but both had to orbit the sun.
B)It demonstrated that Venus could not be in orbit around earth between earth and the sun because it shows "full" and "new" phases that would never occur with geocentric geometry.
C)It showed that Venus had to have a highly elliptical orbit that nearly crosses earth's to produce phases like the moon.
D)It was not an important observation supporting heliocentric theory,but it did work out to be consistent with the theory.

Question 40

Earth hits its perihelion position in January.Solar radiation is proportional to the distance squared between the sun and the earth,so why isn't it hot in "winter" at perihelion?

A)It is; it is called summer in the Southern Hemisphere,and there is just a time lag for the Northern Hemisphere.
B)Precession modifies the effect as the earth wobbles on its axis.
C)The ellipticity of the orbit is small,so the affect is small; seasons are caused by tilt of the earth's orbit.
D)None of these is correct.

Question 41

Why are there only 4-7 eclipses per year?

A)There are more,they just aren't visible on both sides of the earth.
B)The moon's orbit is inclined to the ecliptic and only crosses the ecliptic twice per year.
C)The moon's orbit is inclined to the ecliptic and only crosses the ecliptic 3-4 times per year.
D)There are only 4 full moons and 4 new moons per year,so no more than 4-7 are possible.

Question 42

Axial precession is sometimes called the precession of equinoxes because it results in a gradual shift,relative to the celestial background,of the position where the sun crosses the celestial equator at the equinox.Astrology is a mythology based on things like your "sign" which refers to the position of the sun in the celestial zodiac (the 12 constellations along the ecliptic)on your birthday.This system was established almost two thousand years ago.If this mythology were true (and you believe your horoscope)can you use the dates for your "sign" based on this 2000 year old system?

A)Yes,the dates are fixed; your sign is your sign.
B)Yes,any changes are insignificant in 2000 years.
C)No,although the precession shifts the equinox position,the other zodiac positions do not change because they are fixed to the celestial sphere.
D)No,because 2000 years is almost 1/12,or one full sign shift,in the zodiac,so the 2000 year old signs are off by almost one full sign.

Question 43

The concept that the earth was a sphere was not known until the Renaissance,in Columbus's time.

Question 44

A sidereal day is defined as ________.

A)24 hours in a day
B)the time for one complete revolution of the earth relative to the celestial reference
C)the time between periods when the sun is at the exact same height in the sky,for example,noon
D)24 hours at Greenwich,England

Question 45

The period of time required for the Moon to complete a cycle of phases is called the ________ month.

A)equinox
B)sidereal
C)synodic
D)zodiacal
E)Julian

Question 46

The ancient Greeks proposed an Earth-centered view of the universe.

Question 47

Relative to the celestial background,the moon moves ________.

A)east to west
B)west to east
C)southeast to northwest
D)south to north

Question 48

If you determine the number of days in a year with solar time and sidereal time how would they vary?

A)They wouldn't; a year is always about 365 1/4 days,and the 1/4 day is taken up with leap years.
B)A year measured in sidereal time would be about one day longer than a year based on solar time.
C)A year measured in sidereal time would be about one day shorter than a year based on solar time.
D)A year measured in sidereal time would be about 15 minutes different than a solar day,so the difference only accumulates over time.

Question 49

When the moon appears as a thin crescent in the evening sky,just after sunset,the lunar phase is ________.

A)new moon
B)between new moon and first quarter
C)between first and second quarter
D)between second and third quarter

Question 50

According to the Ptolemaic (Greek)system,the planets have circular orbits.

Question 51

A total eclipse of the Sun is only possible at ________.

A)first quarter
B)second quarter
C)third quarter
D)new moon

Question 52

declination right ascension perihelion equatorial system

Question 53

rotation revolution precession declination

Question 54

The concept that the earth maintained a circular orbit around the Sun was dogma during the middle ages.

Question 55

The length of daylight on the Moon is about ________.

A)24 hours
B)48 hours
C)two weeks
D)one month
E)one year

Question 56

Using the telescope,Galileo discovered that the planet Mars had polar ice caps not unlike those on Earth.

Question 57

During a total lunar eclipse,the moon remains visible because ________.

A)the earth is too far from the moon to totally cover the solar disk
B)the atmosphere of the moon diffuses light from the other side of the moon
C)the atmosphere of the earth refracts light around its perimeter
D)None of the above; the moon completely disappears against the night sky.

Question 58

Galileo Aristotle Kepler Newton

Question 59

The planets maintain elliptical orbits around the Sun.

Question 60

At first quarter it is approximately ________ week(s)until the new moon.

A)1
B)2
C)3
D)4

Question 61

Tycho Brahe discovered the three laws of planetary motion.

Question 62

If you are north of the Tropic of Cancer,you will never see stars south of the celestial equator.

Question 63

Sir Isaac Newton was convicted of heresy for supporting the Sun-centered view of the universe.

Question 64

The ecliptic and zodiac are different names for the same thing

Question 65

The angular distance north and south of the celestial equator is called right ascension.

Question 66

When Earth is the farthest from the Sun,it is said to be in the perihelion position.

Question 67

Earth is closest to the Sun in July.

Question 68

Galileo discovered Jupiter's four largest moons.

Question 69

Patterns or configurations of stars named in honor of mythological characters are called perturbations.

Question 70

The North Star (Polaris)will always be in this position in the night sky.

Question 71

The star Vega will be the North Star in a few thousand years.

Question 72

The length of daylight on the Moon is about one month.

Question 73

Earth is closest to the Sun in January.

Question 74

Galileo discovered that the Sun has "blemishes," which we call sunspots.

Question 75

Galileo believed in a Sun-centered view of the universe.

Question 76

The distance from Earth to the Sun is used to measure distances in the solar system and is called a light year.

Question 77

The apparent annual path of the Sun upon the celestial sphere is called the ecliptic.

Question 78

Tycho Brahe used a telescope to accurately record the position of the planet Mars.

Question 79

The signs of the zodiac used in astrology refer to the constellations that lie along the plane of the ecliptic.

Question 80

Because of axial precession the constellations of the zodiac shift by about 1 month every 2500 years.