Astronomy 121
Examination 1
Questions -- Select the best answer

The first 8 questions refer to the figure below (Sorry, I've lost the exam for now--I reproduced the figure but don't remember the exact locations for various letters, however, you get the idea):

1.  Which letter best marks the location of the North Celestial Pole?

		a.  H


		b.  G


		c.  S


	*       d.  E


		e.  F


2.  Which letter best marks the location of the Vernal Equinox?

	*	a.  A

		b.  C

		c.  D

		d.  G

		e.  H

3.  The ecliptic is best described by which set of letters?

        *       a.  A,B,C,D

		b.  A,E,C,F

		c.  A,B,C,G

		d.  A,D,C,H

		e.  A,G,C,H

4.  The Celestial Equator is best described by which set of letters?

		a.  A,B,C,D

		b.  A,E,C,F

		c.  A,B,C,G

		d.  A,D,C,H

	*       e.  A,G,C,H

5.  In Eugene, OR, fall begins when the Sun reaches which letter?

		a.  A

	*	b.  C

		c.  G

		d.  H

		e.  B

6.  In Eugene, OR, the day with the greatest number of hours of daylight 
    occurs when the Sun is near which of the following letters?

	*	a.  B

		b.  G

		c.  H

		d.  D

		e.  E

7.  The star marked by the letter S has coordinates

		a.  right ascension = 6 h, declination = 45 degrees North

		b.  right ascension = 12 h, declination = 90 degrees North

	*	c.  right ascension = 18 h, declination = 45 degrees North

		d.  right ascension = 0 h, declination = 90 degrees North

		e.  right ascension = 18 h, declination = 90 degrees North

8.  The star marked by the letter S is best viewed by an observer in
    Eugene, OR in

		a.  the spring

	*	b.  the summer

		c.  the fall

		d.  the winter

		e.  Star S is never visible in Eugene, OR

9.  The concept of the Celestial Sphere was originated by

		a.  the ancient Eqyptians

		b.  the American Indians

        *	c.  the ancient Greeks

		d.  the early inhabitants of Australia

		e.  decree of the International Astronomical Union in 1918

10.  The diurnal path of a celestial object is best described as

		a.  a circle centered on the zenith of the observer.

		b.  an ellipse centered on the zenith of the observer.

        *	c.  a circle centered on the North Celestial Pole.

		d.  a circle centered on the Vernal Equinox.

		e.  a circle centered on the Summer Solstice.

11.  The  solar day differs from the  sidereal day because

		a.  the Earth's rotation period is increasing.

		b.  the rotation axis of the Earth is slowly precessing.

	*	c.  the Earth orbits around the Sun.

		d.  the Moon is slowing down the Earth's rotation.

		e.  the Earth's orbital period is slowly increasing.

12.  The  true orbital period of the Earth is given by

		a.  the tropical year.

		b.  the calendrical year.

		c.  the lunar year.

	*	d.  the sidereal year.

		e.  the synodic revolution period.

13.  Suppose that the Earth rotated in the clockwise sense as viewed
     from the North Celestial Pole,  i.e., it spun from east to west,
     while it still orbited about the Sun in the counter-clockwise sense.
     Which of the following statements about this hypothetical Earth is true?

	*	a.  The stars rise in the west and set in the east.

		b.  The solar day is longer than the sidereal day.

		c.  The annual motion of the Sun through the stars is east to west.

		d.  The ecliptic plane is the same as the equatorial plane.

		e.  All of the above are correct statements.

14.  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.

15.  The Greeks supported the notion that the Earth was stationary in 
     the center of the Celestial Sphere by

		a.  simply stating, "that's the way it is, Bud."

		b.  showing that the stars were much smaller than the Earth.

		c.  their failure to detect daily changes in star positions.

		d.  their failure to find other life in the Solar System.

	*	e.  their failure to detect annual shifts in star positions.

16.  In Eugene, OR (latitude = 44 N, longitude = 123 W), the
     altitude of the North Celestial Pole above the horizon is

		a.  0

	*	b.  44

		c.  90

		d.  123

		e.  It depends on the time of year.

17.  Where on the Earth are all visible stars  circumpolar?

	*	a.  the North Pole

		b.  in a small region around Eugene, OR

		c.  the equator

		d.  anywhere in a small region the size of Ohio centered on the North Pole

		e.  anywhere in a small band the size of Rhode Island around the equator

18.  Where must an observer be located on the Earth in order to see the
     entire sky over the course of a year?

		a.  the North Pole

		b.  Eugene, OR (or near Eugene, OR)

	*	c.  the equator

		d.  the South Pole

		e.  near Santiago, Chile

19.   You notice that on the Summer Solstice, the Sun reaches a maximum
      altitude above the southern horizon of 69.5.  What is your
      latitude (on the Earth)?

		a.  lat = 90; you are at the North Pole

		b.  lat = 69.5; you are near the Arctic Circle

	*	c.  lat = 44; you are in Eugene, OR

		d.  lat = 23.5; you are near the Tropical Zone

		e.  lat = 0; you are on the equator

20.  Suppose that the rotation axis of the Earth was perpendicular to
     the ecliptic plane, that is, the tilt of the rotation axis was 0 degrees,
     The seasonal variations on this hypothetical Earth would be

		a.  shorter than for the current Earth

		b.  longer than for the current Earth

		c.  the same as those for the current Earth

	*	d.  mild; seasonal variations would be small

		e.  extreme; seasonal variations would be enhanced

21.  On what day does the Sun rise for an observer at the South Pole of
     the Earth?

	*	a.  the autumnal equinox (Sep 21)

		b.  the summer solstice (June 21)

		c.  the vernal equinox (Mar 21)

		d.  the winter solstice (Dec 21)

		e.  the Sun never rises at the South Pole

22.  The Tropical year differs from the Sidereal year because

		a.  the Earth's rotation period is slowly increasing

	*	b.  of the effects of precession

		c.  the Moon's orbital period is slowly increasing

		d.  the Earth's rotation axis is tilted with respect to the ecliptic

		e.  the Earth's orbital period is slowly increasing

23.  If a total solar eclipse occurred 2 weeks ago, what would be the
     approximate phase of the Moon today?

		a.  new

		b.  first quarter

	*	c.  full

		d.  third quarter

24.  Eclipses do not occur every month because

		a.  the Moon is always in the ecliptic plane

		b.  the Moon is never in the ecliptic plane

		c.  the Earth's axis is tilted with respect to the ecliptic plane

		d.  the Moon's orbit is in the ecliptic plane

	*	e.  the Moon's orbit is tilted 5 with respect to the ecliptic plane

25.  If the angular diameter of the New Moon is slightly less than the angular
     diameter of the Sun, what type of eclipse should occur?

		a.  total solar eclipse

		b.  partial solar eclipse

	*	c.  annular solar eclipse

		d.  total lunar eclipse

		e.  partial lunar eclipse

26.  The annual variations in the appearance of the sky are due to the

	*	a.  orbit of the Earth about the Sun

		b.  orbit of the Moon about the Earth

		c.  orbit of the Sun about the center-of-mass of the Solar System

		d.  rotation of the Earth on its axis

		e.  the rotation of the Sun on its axis

27.  Yesterday I went outside and saw star Z rise at precisely 10:00 p.m.  
     If I go outside tonight, when will star Z rise?

        *       a.  before 10:00 p.m.

		b.  at precisely 10:00 p.m.

         	c.  after 10:00 p.m.

		d.  can't predict when star Z will rise because of precession

28.  The  horns of the crescent moon

		a.  point towards the Sun

		b.  point directly toward the North Celestial Pole

	*	c.  point away from the Sun

		d.  point directly toward the South Celestial Pole

29.  On the winter solstice, the Sun

	*	a.  reaches its farthest point south of the Celestial equator

		b.  crosses the Celestial equator moving northward

		c.  reaches its highest point north of the Celestial equator

		d.  crosses the Celestial equator moving southward

		e.  circles parallel to the horizon for an observer at the equator

30.  The location of the North Celestial Pole is determined by

		a.  the direction in which the Earth orbits about the Sun

		b.  the direction in which the Moon orbits about the Earth

	*	c.  the direction in which the Earth's rotation axis points

		d.  the direction in which the Sun moves on the Celestial Sphere

		e.  the direction in which the Moon rotates on its axis

31.  The Zodiac constellations lie along

		a.  the Celestial equator

		b.  the line-of-nodes

	*	c.  the ecliptic

		d.  the celestial meridian

32.  The assumption that the stars are fixed firmly to the Celestial 
     Sphre turns out to be reasonable because

		a.  stars are, in fact, stationary; they do not move

		b.  stars move very slowly compared to planets; speeds much less than 1 
                    mile per hour

	*	c.  stars are extremely distant

		d.  stars are fairly nearby

		e.  stars are optical illusions

33.  A total lunar eclipse can occur only

		a.  at midnight

		b.  at noon

		c.  when the Moon is new

		d.  when is the Moon is at First Quarter

	*	e.  when the Moon is full

34.  Which of the following is true about the motions of the planets?

		a.  They, in general, move west to east through the stars.

		b.  They move through the Zodiac constellations.

		c.  They rise in the east and set in the west over the course of a day.

		d.  At times, they perform loops on the sky known as Retrograde motion.

	*	e.  All of the above statements about planets are true.

35.  Suppose you are near the equator.  You go out and see the third
     quarter moon and  it is rising.  Roughly, what time is it?

		a.  noon

		b.  sunset

	*	c.  midnight

		d.  sunrise

 36.  Suppose you are standing on the Moon.  You see a  full Earth, 
     what is the phase of the Moon?

	*	a.  New

		b.  First Quarter

		c.  Full

		d.  Third Quarter

		e.  Gibbous

37.   Precession

		a.  is the accuracy with which numbers are given in astronomy

	*	b.  causes the motion of the Earth's rotation axis on the Celestial Sphere

		c.  produces the apparent backward motion of the planets on the sky

		d.  causes the daily eastward motion of the Sun on the Celestial Sphere

38.  Suppose that the Tropical Year was exacltly 365.2 days long.  
     How often would 
     we need leap  years?

		a.  Never

		b.  Once every 10 years

	*	c.  Once every 5 years

		d.  Once every 4 years

		e.  Once every 2 years

39.  The seasons are caused by

		a.  the Sun being closer to the Earth in June than in December

		b.  the tilt of the plane of the Moon's orbit in relation to the ecliptic

		c.  the motion of the Vernal Equinox on the sky

	*	d.  the tilt of the Earth's rotation axis in relation to the perpendicular
                    to the ecliptic

40.  As viewed from the North Celestial Pole, the Sun moves in which
     sense on the Celestial Sphere?

		a.  in the clockwise direction (East to West)

	*       b.  in the counter-clockwise direction (West to East)

		c.  The Sun is fixed on the Celestial Sphere.

		d.  The Sun exhibits both prograde and retrograde motions.

		e.  The Sun moves only north to south on the Celestial Sphere.