Astronomy Test 1 - Introduction - February 3, 2003

Please put your name on the back of the last sheet only, near the staple.

Multiple choice - Place the number corresponding to the best answer in the blank provided.

___ A typical galaxy is a
1-relatively small, icy object orbiting a star.
2-nearby object orbiting a planet.
3-collection of a hundred million or more stars.
4-large, glowing ball of gas powered by nuclear energy.

___ What do we mean when we say that the universe is expanding?
1-Everything in the universe is gradually growing in size.
2-The statement is not meant to be literal; rather, it means that our knowledge of the universe is growing.
3-Average distances are increasing between star systems within galaxies.
4-Average distances between galaxies are increasing.

___ Based on observations of the universal expansion, the age of the universe is roughly
1-between 12 trillion and 16 trillion years.
2-between 12,000 and 16,000 years.
3-between 12 million and 16 million years.
4-between 12 billion and 16 billion years.

___ Suppose we look at two distant galaxies: Galaxy 1 is twice as far away as Galaxy 2. In that case:
1-We are seeing Galaxy 1 as it looked at an earlier time in the history of the universe than Galaxy2.
2-Galaxy 2 must be twice as old as Galaxy 1.
3-Galaxy 1 must be twice as big as Galaxy 2.
4-We are seeing Galaxy 1 as it looked at a later time in the history of the universe than Galaxy 2.

___ Which of the following statements about the celestial sphere is NOT true?
1-The celestial sphere does not exist physically.
2-The "celestial sphere" is just another name for our universe.
3-When we look in the sky, the stars all appear to be located on the celestial sphere.
4-The Earth is placed at the center of the celestial sphere.

___ When standing outside on a clear, dark night, we can see the disk of the Milky Way as a
1-a small grouping of galaxies in the sky.
2-spiraling pinwheel of gas and dust.
3-concentrated island of 400 billion stars.
4-whitish band of light stretching across part of the sky.

___ Which of the following correctly describes the meridian in your sky?
1-A half-circle extending from your horizon due east, through the north celestial pole, to your horizon due west.
2-The point directly over your head.
3-A half-circle extending from your horizon due east, through your zenith, to your horizon due west.
4-A half-circle extending from your horizon due north, through your zenith, to your horizon due south.

___ When traveling north from the United States into Canada, you'll see the North Star (Polaris) getting
1-lower in the sky.
3-higher in the sky.

___ Lunar eclipses can occur only at
1-full moon.
2-third quarter moon.
3-new moon.
4-first quarter moon.

___ The Sun appears lowest in the sky in the northern hemisphere on
1-the winter solstice.
2-the 21st of December.
3-the first day of winter.
4-all of these choices.

___ Local solar Noon is defined as when
1-the Sun is directly overhead.
2-the Sun is overhead in Greenwich.
3-the Sun crosses the meridian.
4-most people eat lunch.

___ If the tilt of the Earth's axis were increased
1-the length of the winter night (the time of continuous darkness) at the North and South poles would be shorter than it is presently.
2-the Sun would be farther North in the Summer and farther South in the winter.
3-there would be no noticeable variation in the seasons from what we see now.
4-there would be no seasonal variation during the year.

___ Based on the date of his or her birth, a person's astrological "sign" is the constellation which
1-is visible at midnight.
2-was hidden by the Sun on that date 2000 years ago.
3-appears to be most like that individual's personality.
4-is between the Sun and Moon.

___ In science, the status of an idea that has been repeatedly verified, giving scientists great confidence, is
1-an experiment.
2-an observation.
3-a hypothesis.
4-a theory.

___ Which of the following is NOT part of a good scientific theory?
1-Scientific theories are based on older theories that have been verified.
2-Scientific theories make predictions of new behavior that can be searched for via new experiments or observations.
3-Scientific theories are proven to be right through many experimental and observational trials.
4-Scientific theories can change in response to observations.

___ The Ptolemaic model of the Universe
1-was used to explain the seasons.
2-(despite being wrong) was able to describe the motions of the planets as well as the modern, Sun-centered model does.
3-was always considered a mere aid in making predictions, but never an accurate depiction of the Universe.
4-used circles upon circles to explain the complex motions of the planets.

___ How will you be able to tell the difference between science and pseudo-science?
1-Always consider the source of your information.
2-Take science classes, learn the basics of science and statistics, and learn how to ask the best questions.
3-Read science news from reputable sources, such as Science or Nature.
4-All of the other answers (and more!)

___ If the Earth's axis were not tilted
1-our year would be much longer.
2-summers and winters would be much more extreme.
3-stars would not rise and set in our sky.
4-we would not have seasons.

___ The Moon completes a cycle of phases roughly once every
1-two weeks

___ The Moon always shows nearly the same face to Earth because
1-the Moon does not rotate.
2-the Moon rotates once in the same amount of time that it takes the Earth to orbit the Sun once.
3-the Moon rotates once in the same amount of time that it takes to orbit the Earth once.
4-sunlight always hits the same face of the Moon.

Short answer - 6 points each (above were 3)

1. Draw and label the positions of the earth, moon and sun and the shadows for a total lunar eclipse.

2. The planet Saturn is about 9 times as far from the sun the earth is from the sun. How many astronomical units from the sun is Saturn?

3. The 23 1/2° tilt of the earth's axis causes the seasons. What two effects of this tilt cause summer to be warmer than winter?

4. Explain in your own words what causes the phases of the moon. Use a diagram if you wish.

5. Why is the hypothesis "Intelligent life exists somewhere else in the universe besides earth" not a scientific hypothesis?