Astronomy 100 Quiz 1       NAME_____________________________

Circle the ONE most comprehensive response.

1. Is it possible to prove, for certain, that a scientific theory is false?

a. Yes, by taking a vote among all scientists who are experts concerning that theory.
b. Yes, by means of a single confirmed experiment that contradicts the theory.
c. Yes, by performing a large number of experiments and finding that the outcomes that dispute the theory outnumber the outcomes that support the theory.
d. No, because it is always possible that future experiments will agree with the theory.
e. No, because science can never be certain of anything.
2. In this age of space exploration, Man has now traveled to the Moon. By how many orders of magnitude (powers of ten) was the distance of the lunar journey greater than that of Columbus' Atlantic ocean crossing when he discovered the Americas?
a.   3
b.   2
c.   6
d.   1
3. An inhabitant of a planet orbiting the star Betelguese observes the flash from the first nuclear weapon on Earth, exploded in July 1945. If this extraterrestrial being were to send a signal to Earth immediately to confirm this sighting, and we were watching her planet, when would we expect to see the signal? (Betelgeuse is 520 light years distant)
a.   2465 AD
b.   2985 AD
c.   2040 AD
d.   1976 AD
4. In a dream, you land on a planet in a location such that all the stars you can see rotate in circular arcs in the sky, and they do not rise or set; a star directly overhead (your zenith) remains stationary. You then walk in one direction a distance of 3000 km to a location such that the stars you now see all set and rise at right angles relative to the E-W horizons. What is the circumference of this dream planet?
a.    1,500 km
b.    3,000 km
c.    6,000 km
d.    9,000 km
e.    12,000 km
5. Is it possible to prove, for certain, that a scientific theory is true?
a. Yes, by means of a single confirmed experiment that verifies the theory.
b. Yes, by carrying out a sufficient number of independently confirmed experimental observations.
c. Yes, by deducing it logically from other scientific theories that are known to be true.
d. No, because experimentalists sometimes make serious mistakes.
e. No, because it is possible that a future experiment will disagree with an aspect of the theory.
6. Which of the following statements about the ecliptic plane is FALSE?
a. It is the plane of the Earth’s orbit around the Sun.
b. During a solar eclipse, the Moon lies in the ecliptic plane.
c. During a lunar eclipse, the Moon lies in the ecliptic plane.
d. The nodes of the Moon’s orbit lie in the ecliptic plane.
e. It is the plane of the Moon’s orbit around the Earth.
7. Why is it winter in Earth’s Northern Hemisphere when it is summer in the Southern Hemisphere?
a. The Northern Hemisphere is further from the Sun than the Southern Hemisphere.
b. The Northern Hemisphere is "on top" of the Earth and therefore receives more sunlight.
c. The Northern Hemisphere is tilted toward the Sun and receives more direct sunlight.
d. The Northern Hemisphere is tilted away from the Sun and receives more indirect sunlight.
8. If the Moon is rising at noon, the phase of the Moon must be
a. first quarter.
b. third quarter.
c. new.
d. full.
9. Why do we see the same face of the Moon at all times?
a. because the other face points toward us only at new moon, when we can’t see the Moon
b. because the Moon does not rotate on its axis
c. because the Moon’s rotation (spin on axis) and orbital periods are equal
d. because the Sun only illuminates one half at a time
e. because the Moon has a nearly circular orbit around the Earth
10. If the angular size of the Moon in the sky is 30 arc-minute, and the angular size of the Sun in the sky is 32 arc-minute, what kind of solar eclipse would an earth-based observer witness, assuming the observer is perfectly aligned with the Sun and Moon?
a. a penumbral solar eclipse.
b. a partial solar eclipse.
c. an annular solar eclipse.
d. a total eclipse.
11. Patterns of stars in constellations hardly change in appearance over times of even a few thousand years. WHY?
a. Stars are fixed and do not move.
b. Stars move, but they move slowly, only a few kilometers in a thousand years.
c. Although most stars move through the sky, the brightest stars do not, and these are the ones that trace the patterns we see in the constellations.
d. The stars in our sky actually move rapidly relative to us - thousands of km/hour, but are so far away that it takes a long time for this motion to make a noticeable change in the sky patterns.
e. Stars within a constellation move together as a group, which tends to hide their actual motion and prevent the pattern from changing.
12. Over a period of one year, what fraction of the overall (night) sky would a Bellingham observer be able to see?
a. 100%
b. about 50%
c. between 50% and 100%
d. a variable amount, depending upon which year
13. When we watch the northern hemisphere nighttime sky, we find that...
a. stars and constellations toward the south slowly rise in the east, pass the meridian, and set in the west.
b. all stars and constellations reach their highest point in the sky at midnight.
c. stars and constellations slowly rise in the west, pass overhead, and set in the east.
d. the stars and constellations remain fixed in our sky, not rising or setting in a time as short as one night because they are so far away.
14. The Sun subtends about 0.5 degree in angular diameter. On the equator, about how long does it take for the Sun to set, from time of first contact with the western horizon to the time the Sun completely disappears below that horizon?
a.  2 seconds
b.  about 1 hour
c.  4 minutes
d.  2 minutes
15.  If the Moon’s orbital plane were exactly aligned with the ecliptic plane (i.e., not tilted 5 degrees)...
a.  there would never be a solar or lunar eclipse.
b.  there would be about a dozen solar eclipses per year and only 1-2 lunar eclipses per year.
c.  there would be a solar eclipse every new moon and a lunar eclipse every full moon.
d.  there would be a solar eclipse every full moon and a lunar eclipse every new moon.
16. What is the difference between a theory and a fact?
a.  A fact is a theory that has been scientifically proven.
b.  A fact is an observation and a theory is an explanation.
c.  A theory is a fact that has withstood the test of time.
d.  A theory is always eventually disproven and facts are forever.
17.  Suppose that at midnight you observe the Moon due south on the meridian. Where will it be two nights later at the same time?
a.  It will be about 26 degrees west of my meridian.
b.  It will be about 26 degrees east of my meridian.
c.  It will be about 26 degrees north of my meridian.
d.  It will be about 26 degrees south of my meridian.
18. You read in a popular children's book that a full Moon is rising at midnight on Halloween.  What is wrong with this statement, and why?
a.  At Halloween, the Earth is near the point in its orbit of the fall equinox, so the Moon will rise near sunset.
b.  Halloween corresponds with the time of the harvest Moon, which will always be rising near sunset to enable night-time gathering of food-crops grown during the summer and fall.
c.  At midnight for any observer, a full Moon will be on the opposite side of the Earth from the Sun, so the Moon will be transiting, not rising.
d.  Nonsense - there is nothing wrong with the statement, because the full Moon will always rise at midnight when the Earth is near fall or spring equinox, and Halloween occurs near fall equinox.
19. You are on the far side of the Moon at its equator. Describe the motions of the stars (not including the Sun) from that vantage point. Remember that the Moon has no atmosphere, so you could always see stars.
a. The stars would be stationary in the sky, because the Moon does not spin relative to the stars.
b. The stars would rotate from east to west with a period of 27.3 days, because the Moon spins on its axis in the same sense as Earth does, once in 27.3 days
c. The stars would rotate from east to west with a period of 1 year, because the Moon orbits the Earth, which orbits the Sun once a year.
d. None of the above.
20. You are still on the far side of the Moon at its equator.  Would Polaris remain stationary in the sky, as it does from Earth? Why or why not?
a.  Polaris will remain stationary in the sky, along with all stars, because the Moon does not spin on an axis.
b.  Polaris will remain stationary in the sky, because Polaris would remain stationary for all satellites orbiting Earth, provided the satellites orbit in the ecliptic plane.
c.  Polaris would not remain stationary in the sky because the Moon's orbital plane around the Earth is not aligned with Earth's orbital plane around the Sun
d.  Polaris would not remain stationary in the sky because the Moon's spin axis is not aligned with Earth's spin axis.