Test: Part One

Do not refer to the text when taking this test. A good score is at least 30 correct. Answers are in the back of the book. It’s best to have a friend check your score the first time, so you won’t memorize the answers if you want to take the test again.

1. A solar flare can produce

(a) disturbances in the Earth’s magnetic field.

(b) lunar libration.

(c) a total solar eclipse.

(d) a dark spot on the Sun.

(e) A reddish glow on the Moon.

2. Longitudes are not assigned values greater than 180 degrees east or 180 degrees west because

(a) doing so would result in a redundant set of coordinates.

(b) the King of England forbade it in the seventeenth century, and no one has contradicted him since.

(c) Galileo saw that such a thing could not possibly occur.

(d) 180 degrees represents a full circle.

(e) Oh, but they are! Latitudes are commonly assigned values greater than 180 degrees east or 180 degrees west.

3. The Sun’s declination is 0 degrees on

(a) January 21.

(b) July 21.

(c) October 21.

(d) December 21.

(e) none of the above dates.

4. The Moon’s diameter is

(a) about 1/81 that of the Earth.

(b) about 1/30 that of the Earth.

(c) about 1/4 that of the Earth.

(d) about the same as that of the Earth.

(e) variable, depending on its phase.

5. Which of the following constellations consists of a group of stars early in their lifespans, and still shrouded in the gas and dust from which they formed?

(a) The Pleiades

(b) Orion

(c) Ursa Minor

(d) Pollux

(e) Bootes

6. In the southern hemisphere, the Sun’s right ascension is 12 hours on or around the twenty-first day of

(a) September.

(b) December.

(c) March.

(d) June.

(e) no month; the Sun never reaches a right ascension of 12 hours in the southern hemisphere.

7. The reddish color of the Moon during a total lunar eclipse is caused by

(a) sunlight passing through the Earth’s atmosphere.

(b) sunlight reflected from the Earth back to the Moon.

(c) sunlight scattered by particles in interplanetary space.

(d) solar flares.

(e) solar prominences.

8. If you were at the south geographic pole, the elevation of Polaris, the North Star, would be approximately

(a) –90°.

(b) 0°.

(c) +90°.

(d) 180°W.

(e) 180°E.

9. Scattered artificial light, such as that produced by the lights of a large city,

(a) obscures many of the dimmer stars and constellations, which can be seen easily from locations in the outback.

(b) causes the Moon to appear larger than it really is.

(c) affects star visibility near the zenith more than star visibility near the horizon.

(d) has no effect on stargazing whatsoever.

(e) renders the dimmest stars more visible than they would be in the outback.

10. If Orion, the hunter, appears to be standing upright in the southern sky on a January evening as seen from New Hampshire, then at the same time, to viewers in Santiago, Chile, the hunter is

(a) standing upright in the northern sky.

(b) lying on his side in the northern sky.

(c) standing on his head in the northern sky.

(d) invisible because the seasons in the southern hemisphere are inverted with respect to the seasons in the northern hemisphere.

(e) invisible because it would never rise above the horizon.

11. The constellation Octans, near the south celestial pole, can be seen rising in the east on evenings in the month of

(a) April.

(b) July.

(c) October.

(d) January.

(e) None of the above

12. The relatively dark, central part of a sunspot is called the

(a) core.

(b) ecliptic.

(c) pole.

(d) umbra.

(e) synodic.

13. Assuming that interstellar travel is possible and that humans will do it someday, the constellations will not be usable by the captains of interstellar spaceships because

(a) stars are invisible at warp speeds.

(b) the constellations have their characteristic shapes only from the vantage point of our solar system and its vicinity.

(c) all the stars will have moved to new positions and the present constellations will no longer exist.

(d) they do not radiate electromagnetic fields of the proper type.

(e) Wrong assumption! The constellations will be perfectly good navigational tools for long-distance interstellar travel.

14. Meridians on the Earth

(a) are circles centered at the equator.

(b) are circles centered at the south pole.

(c) are half circles connecting the north and south poles.

(d) are half circles parallel to the equator.

(e) are straight lines passing through the Earth’s physical center.

15. At which of the following times of year would the number of hours of daylight change the least rapidly from one day to the next?

(a) Late June

(b) Late August

(c) Early October

(d) Early March

(e) Early April

16. The angular diameter of the Moon, considered as a whole and as viewed from the Earth, is

(a) about 1/6 the angular diameter of the Earth.

(b) about 1/2 the angular diameter of the Sun.

(c) largest at apogee, and smallest at perigee.

(d) tilted about 5 degrees with respect to the ecliptic.

(e) about the same as the angular diameter of the Sun.

17. How many hours of right ascension are there in 30 degrees of arc, measured along the ecliptic?

(a) One hour

(b) Two hours

(c) Three hours

(d) Four hours

(e) Six hours

18. Which constellation, easily visible at temperate latitudes in both the northern and southern hemispheres, is also known as the hunter?

(a) Hercules

(b) Libra

(c) Orion

(d) Pollux

(e) Ursa Major

19. An effect of libration is:

(a) that the Moon’s orbit is not a perfect circle.

(b) to accelerate solar particles as they encounter the Earth’s magnetic field.

(c) to cause the tides to lag the gravitational effects that produce them.

(d) to let us see slightly more than half the Moon’s surface.

(e) to allow viewing of the solar corona during a total solar eclipse.

20. The summer solstice in London, England, occurs within a day of

(a) March 21.

(b) June 21.

(c) September 21.

(d) December 21.

(e) None of the above

21. At the time of the first-quarter moon,

(a) the Earth is directly between the Sun and the Moon.

(b) the Moon is directly between the Sun and Earth.

(c) the Sun is directly between Earth and the Moon.

(d) the Moon is 90 angular degrees from the Sun in the sky.

(e) the Moon is 180 angular degrees from the Sun in the sky.

22. Which of the following constellations lies in the same direction as the center of our galaxy?

(a) Cancer

(b) Ursa Minor

(c) Gemini

(d) Orion

(e) Sagittarius

23. From which vantage point on the Earth would the star Sirius rise in the west and set in the east?

(a) The far northern hemisphere

(b) The north pole

(c) The equator

(d) The far southern hemisphere

(e) Nowhere

24. What do the two stars Epsilon Eridani and Tau Ceti have in common?

(a) They are both red giants.

(b) They are members of a double-star system.

(c) They have both been suggested as possibly having Earthlike planets.

(d) They are both in the process of formation.

(e) Nothing; these are the names of constellations, not stars.

25. As seen from a midlatitude location in the southern hemisphere at around sunset, the first-quarter moon

(a) would be in the northern sky.

(b) would be in the southern sky.

(c) would be rising in the east.

(d) would be beneath the horizon and therefore not visible.

(e) might or might not be visible depending on the season of the year.

26. The Sun’s declination is approximately +90° on or around the twenty-first day of

(a) September.

(b) December.

(c) March.

(d) June.

(e) no month; the Sun never reaches a declination of +90°.

27. The brightest star in the sky, other than the Sun, is

(a) Procyon.

(b) Deneb.

(c) Rigel.

(d) Sirius.

(e) Aldebaran.

28. Suppose that we make a scale model of the Earth-Moon system. The Earth’s is represented by a beach ball 1 meter in diameter. The Moon would best be represented as:

(a) a basketball 30 meters away.

(b) a baseball 5 meters away.

(c) another beach ball 100 meters away.

(d) a marble 3 meters away.

(e) another ball, but we need more data to know how big it should be and how far from the beach ball to place it.

29. Azimuth is essentially the same thing as

(a) celestial longitude.

(b) right ascension.

(c) compass bearing.

(d) elevation.

(e) declination.

30. In the southern hemisphere, azimuth 0° is sometimes considered to be

(a) east.

(b) west.

(c) south.

(d) at the zenith.

(e) at the nadir.

31. The Sun’s rotational period, averaged between the poles and the equator, is roughly

(a) the same as the period of the Moon’s orbit around the Earth.

(b) the same as the Earth’s rotational period.

(c) one synodic day.

(d) synchronized with the tides.

(e) synchronized with the equinoxes.

32. At the north celestial pole,

(a) none of the observed constellations are circumpolar.

(b) the stars all stay above the horizon for 11 hours and 58 minutes a day and stay below the horizon for the other 11 hours and 58 minutes.

(c) half the constellations are circumpolar.

(d) all the observed constellations are circumpolar.

(e) Polaris is exactly on the northern horizon.

33. Suppose that you are in Calcutta, India, on March 21. For how long is the Sun above the horizon that day, measured with respect to the center of its disk?

(a) Much longer than 12 hours

(b) A little longer than 12 hours

(c) Exactly 12 hours

(d) A little less than 12 hours

(e) Much less than 12 hours

34. The constellations as we know them today would no longer exist if we were to travel in time

(a) 100 years into the future.

(b) 200 years into the future.

(c) 300 years into the future.

(d) 400 years into the future.

(e) The constellations would appear the same as seen from all the above time-journey destinations.

35. Magellanic Clouds are

(a) high-altitude weather phenomena visible long after sunset.

(b) vast tracts of interstellar dust.

(c) a part of the Sun’s corona.

(d) caused by solar flares.

(e) none of the above.

36. The Sun derives its energy primarily from

(a) hydrogen combustion.

(b) hydrogen fusion.

(c) matter-antimatter reactions.

(d) nuclear fission.

(e) Gravitational pressure.

37. From April 1 to July 1, as viewed at 10:00 P.M. from a midlatitude northern place such as Colorado, the circumpolar constellations appear to rotate

(a) 90 degrees clockwise.

(b) 90 degrees counterclockwise.

(c) 180 degrees.

(d) 0 degrees; they are in the same positions.

(e) by some amount, but we need more information to quantitatively answer this question.

38. In a few minutes on a clear, starry night, a star at the zenith will move toward the

(a) north celestial pole.

(b) south celestial pole.

(c) vernal equinox.

(d) celestial equator.

(e) none of the above.

39. As seen from the Earth’s equator, Polaris is approximately how many angular degrees from the zenith?

(a) 0°

(b) 30°

(c) 60°

(d) 90°

(e) There is not enough information given here to answer this.

40. The circumference of the ninetieth parallel in the northern hemisphere is

(a) the same as that of the equator.

(b) half that of the equator.

(c) one-third that of the equator.

(d) zero because it is the north geographic pole.

(e) impossible to determine without more information.