SCI 103 Feb 2007

First Astronomy Exam: The Apparent Motion of the Stars, Sun, Moon and Planets and their interpretation in Copernican Astronomy.

Name______

Class Meeting Time (Circle one)

MWF 8:00 MWF 9:05 TTh 4:30 TTh 6:00


The boxes below represent a hypothetical view of the stars looking North, East and South at 25° North latitude. Make the following marks in each of the boxes as directed in the text to the left of each box.

A. 

In the space below write a brief, but complete, paragraph that describes the apparent motion of the Sun on diurnal and annual timescales. Include all quantitative information such as times and angles.

The sketch to the right shows the Moon in a certain phase.

Name the phase of the Moon shown.

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Estimate the number of days till the next Full Moon

______Days

The position of the Sun and Moon are show on the 360° Mercator view of the sky below. Show your work in the margins.

·  Label the approximate position of the Sun in 7 months from the position shown.

·  Label the approximate position of the Moon in 2 weeks from the position shown.

Around 1600 AD, Johannes Kepler discovered two “laws” of planetary motion that removed the last vestiges of Aristotle from the Copernican model of the Universe and correct two flaws in Copernicus’ original model. What are those two laws and how are they contrary to Aristotelian philiosophy.

In a sentence or two explain how the modern Copernican model of the Universe explains the occurrence of retrograde motion for the superior planets.

Please choose one of Galileo’s telescopic observations of either Jupiter, or Venus and briefly describe what he saw and how it contradicted the Aristotelian Model of the Universe.


Multiple Choice Questions: Answer on the provided Scantron Answer Sheet.

1)  Imagine that you are visiting OCC’s sister University of Namibia located next to the country of South Africa. You step outside at night to see the stars. Where would you look to see Polaris?

A)  North, near the horizon (0 altitude)

B)  Near the zenith (90 altitude)

C)  North, near 43 altitude

D)  Northwest, in the direction towards the U.S.A.

E)  Polaris cannot be seen from this location.

2)  The long exposure image of star trails shown to the right was taken while looking toward the east. From which of the locations listed below was the image obtained?

A)  Fairbanks, Alaska (Latitude 65N)

B)  Syracuse, New York (Latitude 43N)

C)  Miami, Florida (Latitude 26N)

D)  Phitsanulok, Thailand (Latitude 0N)

E)  Sydney, Australia (Latitude 34S)

3)  In which of the below locations would the northern star Vega (Declination = +40) be above the horizon for the longest time?

A)  Fairbanks, Alaska (Latitude 65N)

B)  Syracuse, New York (Latitude 43N)

C)  Miami, Florida (Latitude 26N)

D)  Phitsanulok, Thailand (Latitude 0N)

E)  Sydney, Australia (Latitude 34S)

4)  During which of the following months of the year will the Full Moon be lowest in the night sky (i.e. which month will the Full Moon act most like a southern star)?

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A)  December

B)  March

C)  June

D)  September

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5)  Imagine you are taking a leisurely sail down the inter-coastal waterway from New York to Miami. Each night on your journey of a few weeks, you spend some time observing the stars. Which of the statements below would represent one of your observations?

A)  The region of the sky that was circumpolar diminished each night.

B)  Polaris was seen higher in the sky on each succeeding night.

C)  The northern stars were above the horizon longer each succeeding night.

D)  Stars near the celestial equator were above the horizon for about 8 hours.

E)  All of the above were observed

Use the drawing below showing the Sun and several constellations to answer the next two questions.

6)  If you could see stars during the day, the drawing above shows what the sky would look like at noon on a given day. The Sun is near the stars of the constellation Gemini. Near which constellation would you expect the Sun to be located at sunrise?

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A)  Leo

B)  Cancer

C)  Gemini

D)  Taurus

E)  Pisces

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7)  Which constellation will be highest in the sky 6 hours after the time shown in the drawing above?

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A)  Leo

B)  Cancer

C)  Gemini

D)  Taurus

E)  Pisces

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8)  Yesterday you went outside and saw the star Bellatrix rise at precisely 10 p.m. Two weeks from now, at what time will Bellatrix rise?

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A)  around 8 p.m.

B)  around 9 p.m.

C)  around 10 p.m.

D)  around 11 p.m.

E)  around midnight

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Use the graph provided below, on which an imaginary planet’s motion has been plotted over several months, to answer the next question.

9)  For how many days would this planet have appeared to move with retrograde motion?

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A)  10 days

B)  12 days

C)  15 days

D)  17 days

E)  32 days

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10) What time is it when the moon phase shown at right

first begins to rise above the horizon?

A)  in the early morning

B)  at noon

C)  in the mid-afternoon

D)  in the evening

E)  at midnight

11) Imagine you see Mars rising in the east at 10:10 pm. Six hours later what direction would you face (look) to see Mars?

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A)  toward the north

B)  toward the east

C)  toward the south

D)  toward the west

E)  directly overhead

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12) Which Moon position (A-E), shown in the diagram at right, best corresponds with the moon phase shown below?

13) The Moon appears to cycle around the zodiac once every______.

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A)  23 hours 56 minutes

B)  24 hours

C)  27.3 days

D)  29.5 days

E)  365.25 days

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14) The planet shown in the drawing at right obeys Kepler’s Second Law. Each lettered position represents the location for the planet during a particular day in a year. At which lettered positions would the planet move the most during a period of a day?

15) The figure at right shows a stick and its shadow at noon for an observer in the continental U.S. on Mar 22 (Spring Equinox). How will the shadow length at noon change during the course of the following week?

A)  The Shadow length will be longer than on Mar 22.

B)  The Shadow length will be the same as on Mar 22.

C)  The Shadow length will be shorter than on Mar 22.

D)  The shadow will not appear because we are in Syracuse and the Sun never shines in Syracuse.

A B C D E

16) If the moon is in the full phase today, how many of the moon phases shown above (A-E) would the moon go through during the next 13 days.

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A)  none

B)  only one

C)  two

D)  three

E)  more than three

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17) Polaris has not always been the “North Star”. Which of the statements below best describes the reason why Polaris has not always been the “North Star”?

A)  The stars are not really fixed to the celestial sphere and the motion of Polaris through space will move it away from the celestial pole and, in time, another star will move into the space to become the “pole star”.

B)  The rotation period of the Celestial Sphere is slowly increasing causing Polaris to slowly move away from the celestial pole.

C)  The Celestial Sphere is slowly tipping over so that the North Celestial Pole will become the South Celestial Pole in about 26,000 years.

D)  The Earth’s rotation axis “wobbles” around a cone shape every 25,800 years.

18) Which of the following is a FALSE statement about the motions of the planets?

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A)  The planets move through the Zodiac constellations.

B)  Only the planets whose orbits are larger in size than that of the Earth exhibit retrograde motion

C)  The planets orbit roughly in the ecliptic plane.

D)  Only planets whose orbits are smaller in size than that of the Earth exhibit a new phase for observers on or near the Earth.

E)  The planets rise in the east and set in the west, even when they undergo retrograde motion.

19) The figure to the right illustrates a

hypothetical sunset and a planet

appearing in the twilight. The

planet has a measured elongation

angle of 35 from the Sun. Which

of the planets listed below could

NOT be seen in this configuration?

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A)  Venus

B)  Mars

C)  Mercury

D)  Jupiter

E)  It could be any of these planets.

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20) Which of the statements listed below best represents the apparent relationship between the Sun and the Superior Planets?

A)  The Superior Planets only go retrograde when in opposition to the Sun.

B)  The Superior Planets have a maximum elongation and appeared “tied” to the Sun.

C)  The Superior Planets are never seen at opposition to the Sun.

D)  The Superior Planets only go retrograde when in conjunction to the Sun.

21) The Moon is full. At what time does the Moon appear highest in the sky?

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A)  Noon

B)  Sunset

C)  Midnight

D)  Sunrise

E)  It depends on the season.

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22) The daily motion of celestial objects is caused by ______.

A)  the Earth's revolution about the Sun

B)  the Earth's rotation on its axis

C)  the motion of the Moon about the Earth

D)  the precession of the Earth's axis of rotation

E)  the Sun's motion through the stars

23) On the winter solstice, the Sun ______.

A)  crosses the Celestial equator moving southward

B)  crosses the Celestial equator moving northward

C)  the shortest day of the year occurs

D)  reaches its furthest point south of the Celestial equator

E)  circles parallel to the horizon for an observer at the equator

24) The ancient Ptolemaic astronomers had deduced an order for the planets as one proceeded away from the Earth towards the stellar sphere. On which of the following apparent physical properties of the planets was this order based upon?

A)  Apparent Magnitudes of the Planets (i.e. their brightness)

B)  Maximum elongation angles

C)  Periods of retrograde motion

D)  Apparent sidereal periods

E)  Their mythological hierarchy

Please evaluate the following numerical problems.

Using the fact that our solar system has a diameter of about 40 AU and that the nearest star is about 4x1013 km away, calculate the number of solar systems that could fit between the Sun and the next nearest star.

On one particular night, an astronomer measures the angular size of the Moon through his/her telescope to be 32 arcminutes. Knowing that the diameter of the Moon is 3,476 km, what is the distance to the Moon at that time?

Relevant Formula:

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