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27 Cards in this Set
- Front
- Back
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What forms in the great clouds of gas and dust in the spiral arms of a galaxy?
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stars
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How many stars are there in our milky way galaxy?
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100,000,000,000
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How long does it take light to cross the diameter of our milky way galaxy?
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80,000
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During a lunar eclipse what is the correct ordering of celestial bodies?
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Sun,Earth,Moon
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The moon appears darkest when it passes into which part of the Earth's shadow?
A. The penumbra B. The Umbra C. The Annulus |
B. The Umbra because it is the darkest part of the shadow
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Why does the moon turn red during an annular eclipse?
A. Dust particles in outer space make the moon appear red B. Scattering of blue light in the Earth's Atmosphere C. The surface of the Moon has a reddish tent |
B. Scattering of blue light in the Earth's Atmosphere
This is also the reason we have red sunsets |
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What is the Sidereal Month?
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One lunar orbit with respect to the stars it takes 27.3 days
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What is the Synodic Month?
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The time it takes for a lunar phase to complete. It takes 29.5 days
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The moon moves exactly along the ecliptic. True or False
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False it moves along but not exactly along the ecliptic
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What is the ecliptic?
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The apparant path of the sun around the sky
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Which of these statements are true?
A. The moon orbits eastward around the Earth once every 29.53 days B. Since a full moon occurs when the moon is on the opposite side of Earth as the sun it is only visible at night C. Quarter phases occur between the new and full phases D. The Lunar phase changes as the moon passes in and out of Earth's shadow E. During the new phase no sunlight reaches the side of the moon facing the Earth |
B,C,E
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Why don't eclipses occur every month?
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Because the moon is not always on the ecliptic
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How can scientists predict when eclipses will occur
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Because they occur in a repeating pattern
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The point directly overhead on the sky
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Zenith
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The apparent motion of an object against a background as the observer's position changes is the? And why does it occur?
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Parallax, because of Earth's motion around the Sun during a year
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Once a distance to an object is accurately known the true physical size of an object can be determined by measuring its
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angular diameter
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How far is an AU?
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150 million km or the distance from Earth to the Sun
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What is a light year?
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The distance light or any electromagnetic radiation travels in one year. About 10^13 km
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How fast does light travel?
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300,000 km/sec
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The circle where the Earth and sky appear to meet is
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Horizon
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If two cities have about the same latitude but different longitudes the night's sky in the two places:
A. will have completely different sets of constellation B. Will look about the same C. Will have partially different constellations |
B because they both have the same zenith point and the same horizon
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In winter Earth's axis points toward the star Polaris. In Spring.
A. The axis points toward the sun B. The axis points toward Vega C. The axis still points toward Polaris |
C Since the star at Earth's NCP is the same star over the course of the year Earth's rotation axis must point the same direction in space as it orbits the sun
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If the Sun rises precisely in the east:
A. It must be the day of the summer solstice B. It must be the day of either the spring or fall equinox C. You must be located at the Earth's equator |
B In the northern hemisphere the sun rises north of due east in the summer and south of due east in the winter
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When it is winter in Australia, it is:
A. Winter in the United States B. Summer in the United States C. Spring in the United States |
B
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If the Moon orbited closer to the Earth than it does currently, how would the following change?
i. The number of total eclipses would: A.Increase B. Decrease C. Remain the same ii. The number of annular solar eclipses would: A. increase B. Decrease C. remain the same |
i. A
ii. B For a total eclipse to occur the apparent size must be equal or greater. For Annular eclipses it must be less apparent than the size of the sun |
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Because of their higher frequencies, X-rays travel through space faster than radio waves.
A. True B. False |
B Both travel the same speed
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Radios and cell phones work inside brick buildings because bricks are opaque to visible light, but transparent to radio waves.
A. true B. false |
A
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