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78 Cards in this Set
- Front
- Back
The Milky Way Galaxy is |
a disk-shaped collection of more than 100billion stars, including the Sun. |
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Which of the following has the various objectslisted in order from smallest to largest? |
the solar system; the Milky Way; the Local Group |
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Most of the material that makes up Earth andall life on Earth, including humans, was formed |
inside stars that died before Earth formed. |
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When we look at the most distant observableobjects in the universe, we see them |
as they were about 14 billion years ago |
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What is the observable universe? |
everything out to a distance of about 14 billionlight-years from Earth |
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Which of the following has astronomicaldistances listed in order from smallest tolargest? |
1 AU, the size of the solar system, 1 light-year |
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Which of the following distances isapproximately equal to the distance from theSun to Earth? |
8 light minutes |
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The International Astronomical Union does notclassify Pluto as a planet because |
it has not cleared its orbital neighborhood ofother objects |
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The distance to the nearest star to the Sun is |
about 4 light-years |
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The diameter of the Milky Way is about |
100,000 light-years |
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If the Sun were reduced to the size of agrapefruit, Earth on the same scale would be |
the size of the tip of a ballpoint pen, about 15meters away from the Sun |
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If the age of the universe were compressed toone year, with the Big Bang on January 1,about when did the solar system form? |
in September |
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If the age of the universe were compressed toone year, with the Big Bang on January 1,about when did the Milky Way Galaxy form |
in February |
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If you could count all the stars in the Milky WayGalaxy at a rate of one star per second, itwould take |
about 3000 years |
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Which of the following ranks your differentastronomical motions from slowest to fastest? |
rotation of Earth; motion of Earth around the Sun;motion of the Sun around the center of the Milky Way |
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Your speed due to Earth's rotation is |
about 1,000 km/hour |
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Ever since the Big Bang |
space has continued to expand with clusters of galaxiesmoving away from each other, but stars remaining ingalaxies and galaxies remaining in clusters |
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The Sun completes one revolution of the MilkyWay galaxy every |
230,000,000 years |
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Earth's axis of rotation is tilted about 23.5degrees relative to |
the axis of its orbit around the Sun |
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Which of the following astronomical endeavorshas not affected human history |
All of the above have affected human history |
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The ecliptic is |
the path of the Sun on the celestial sphere AND the projection of Earth's orbit onto the celestialsphere |
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The meridian is |
the boundary between the eastern and westernhalves of your local sky |
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All of the following are points on your local sky.Which one does not move on the celestialsphere over the course of a day? |
the north celestial pole |
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If the Sun and a constellation are at the samelocation in your local sky, then that constellationis |
visible at a different time of year AND part of the zodiac |
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A star near the north celestial pole, observedfrom the northern hemisphere |
will never rise or set AND is called a circumpolar star |
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In order to see all of the celestial sphere atnight, one must |
observe from different longitudes |
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On the (northern) spring equinox the Sun |
all of the above |
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The Sun is at its most southern position on thecelestial sphere |
on the winter solstice (December 21) |
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If you are at a latitude of 23.5 degrees north,when will the Sun be directly overhead? |
at noon on the summer solstice (June 21) |
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Which lists the various motions of Earth inincreasing order of the period (duration) of themotion |
rotation, revolution, precession |
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Which of the following is not changed by theprecession of Earth's axis? |
the location of the North Celestial Pole in yourlocal sky |
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When the phase of the Moon is full |
the Moon and Sun are on opposite sides of Earth. |
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When the phase of the Moon is gibbous |
more than half of the visible face of the Moon isilluminated AND the Moon is closer to Full Moon than to New Moon |
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What time does the first quarter moon rise? |
noon |
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When the Moon passes through Earth's shadow,this is called |
a lunar eclipse |
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Which of the following results in an annularsolar eclipse? |
Earth passes behind the Moon's umbra |
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Lunar eclipses do not occur every monthbecause |
the orbit of the Moon is tilted relative to theecliptic. |
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The Saros cycle describes |
the 18+ year cycle of lunar and solar eclipses. |
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What causes the apparent retrograde motion ofMars? |
When Earth passes Mars it appears to change itsmotion relative to the background stars. |
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Stellar parallax is |
the changing position of nearby stars comparedto background stars as Earth orbits the Sun. |
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Scientific thinking is |
all of the above |
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Which of the following is not an example ofmeasurements of ancient astronomers? |
All of the above were measurements made byancient astronomers. |
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Which is longer, a solar year or a lunar year? |
A solar year, because a lunar year is 12 lunar monthsthat are 29–30 days long each, for a total of 354–355days |
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What does the 19-year Metonic cycle describe? |
the time it takes for phases of the Moon to repeat on thesame dates |
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How did Ptolemy's model differ from Aristotle'smodel of the universe? |
Ptolemy's model had the planets moving in smaller circlesattached to the larger spheres. |
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How was the great library of Alexandriadestroyed? |
It was destroyed deliberately by people in the 5th centuryA.D. |
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Why didn't scientific thinkers immediatelyaccept the Copernican model of the solarsystem? |
B and D |
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Who observed a nova in 1572, showing thatthere could be changes in the realm of theheavens? |
Tycho Brahe |
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Which of the following is not a contributionmade by Tycho Brahe to the CopernicanRevolution? |
He measured the parallax of stars, showing that the Earthorbits the Sun. |
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Which of the following is not one of Kepler'slaws of planetary motion? |
The rotation of a planet is always aligned with itsorbital motion around the Sun. |
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Which of the following parts of an ellipse is ameasure of its shape? |
the eccentricity |
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Which of the following was not an observationmade by Galileo supporting the Sun-centeredmodel? |
He measured the parallax of a comet. |
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A scientific model |
uses math and logic to describe and predict thebehavior of a real-world system. |
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The concept of a scientific model comes from |
Greek philosophers. |
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If an experiment or observation contradicts ascientific theory, then |
the theory must be revised to account for the newdata, or discarded. |
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Which of the following is not a hallmark ofscience? |
A scientific theory is built on logic and common sense toexplain observed phenomena. |
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Which of the following is an astrologicalprediction? |
When Saturn enters a particular constellation, theweather will improve. |
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Astrology is |
not a scientific enterprise because it does not maketestable predictions. |
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Which of the following is not changing forsomeone driving a car in a circle at 30 milesper hour? |
acceleration |
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What does a force acting on an object do to thatobject's motion? |
A force changes an object's momentum. |
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Space Station astronauts are weightless because |
their acceleration is equal to the accelerationdue to gravity. |
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If you take off in a rocket accelerating upward |
your weight increases and your mass stays thesame. |
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Which of the following was Newton's insightabout gravity? |
It is responsible for the motion of the Moonaround Earth. |
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Newton's second law of motion states that |
the acceleration of an object is equal to the force actingon it divided by its mass. |
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All of Newton's laws of motion express theconcept that |
a force (and only a force) always changes themomentum of an object. |
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Which of the following describes how a rockettakes off? |
The backward momentum of the rocket exhaust iscanceled by the forward momentum of the rocket. |
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When two objects collide |
all of the above |
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What is required to change an object's angularmomentum? |
a twisting force |
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The energy of Earth's rotation is an example of |
kinetic energy |
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When a ball is dropped, some of the ball'senergy changes from |
gravitational potential energy to kinetic energy |
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Which of the following processes violates aconservation law? |
An object orbiting the Sun and affected only by the Sun'sgravity spirals into the Sun |
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How does the force of gravity between twoobjects depend on the distance between theobjects? |
It increases in proportion to 1/distance squared. |
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What happens to the energy of an object whileit follows an unbound orbit around the Sun? |
The total remains constant while gravitational potentialenergy is converted to kinetic energy as it approachesthe Sun. |
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The masses of orbiting objects can bedetermined from |
Newton's version of Kepler's third law. |
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Objects on bound orbits |
all of the above |
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The Moon always keeps the same face towardEarth because |
friction due to tides slowed the rotation of the Moon untilit reached the point where it always keeps the same facetoward Earth. |
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Tidal forces from the Moon and Sun add up tomake larger tides on Earth when the Moon is |
new and full. |
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The acceleration due to gravity of an object onthe surface of Earth depends on |
the radius of Earth and the mass of Earth. |