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215 Cards in this Set
- Front
- Back
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What are the largest known structures in the universe?
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Filaments and walls outlining voids.
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North is up in this figure. (picture is of the Earth). Can we tell whether the daylight and darkness line at the right is the sunset line or the sunrise line?
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It is the sunset line because Earth rotates counterclockwise when viewed from ABOVE Earth's North Pole.
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Cooler days in winter are due to:
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Less direct Sunlight, therefore less heating and fewer hours of sunlight.
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Which property of a star is represented by the different size dots in this figure?
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Apparent brightness
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a) Use what you learned in Chapter 1 to rank the following objects from smallest to largest:
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Smallest:
Earth Sun Solar system Milky Way Galaxy at largest |
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b) Rank the following objects from largest to smallest:
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Largest: filament
Galaxy Star Planet at the smallest |
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a) Rank the following distances in order from smallest to largest:
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Smallest:
Earth to moon Earth to sun Sun to nearest star Milky Way Galaxy to next nearest galaxy as largest |
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b) Rank the ratio of the distance compared to the size of the objects involved in order from largest to smallest:
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Largest:
Sun to nearest star Earth to sun Earth to moon Milky Way at smallest |
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Which of the following descriptions is a definition of an astronomical unit?
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The average distance between Earth and the sun.
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What types of distances are typically listed in astronomical units?
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Distances in the solar system.
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The number 7.14 x 10(6) is equivalent to which of the following?
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7,140,000
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Which of the figures shown here is that of a single galaxy?
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Figure C (of a galaxy)
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What does the size of the star image in a photograph tell you?
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The larger the Star's image is in a photograph, the brighter the star appears in the sky
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About how many stars in our home galaxy, also known as the Milky Way Galaxy?
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Over 100,000,000,00
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Approximately how many astronomical units (AU) are there in one light year?
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63,0000
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what is the difference between the Milky Way and the Milky Way Galaxy?
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The Milky Way is a fairly narrow band of faint diffuse light around the celestial sphere. The Milky Way Galaxy is a spiral galaxy of about 100 billion stars.
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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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Which of the following lists is in order of increasing size?
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Solar system<Milky Way Galaxy<Universe
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a) Which planet is currently the outermost in our solar system?
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Neptune
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b) Is it possible that the answer to the last question could change? Why?
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No, the outermost planet is always the same.
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c) Which planet on average is the outermost in our solar system?
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Neptune
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Comment on the line between daylight and darkness on the far right of the figure below. (Earth)
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This is the sunset line, because Earth rotates from west to east.
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How many miles does a runner travel in a five-kilometer race?
END OF CHAPTER ONE--------------------------- |
about three miles (3.25)
END OF CHAPTER ONE--------------------------- |
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Use your knowledge of star names and constellations.
a) Which star is probably brightest? b) Which star is probably dimmest? c) Which star is probably brightest? d) Which star is probably dimmest? |
a) a Ursae Majoris
b) e Ursae Majoris c) e Pegasus d) e Scorpii |
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Which of the following is true for an observer located at the tip of the umbra in this figure?
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The angular size of the tack is the same as the angular size of the light source.
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a) If the Earth's tilt were 13.5 degrees instead of 23.5 degrees, the path of the Sun would be:
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Not as far north in summer nor as far south in winter.
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b) Just as the Sun sets, the shadows are:
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Always the same length BUT pointed to a different compass point according to the season.
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c) Cooler days in winter are due to:
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Less direct Sunlight, therefore less heating and fewer hours of sunlight.
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Which type of eclipse may be visible to all the people on one side of Earth?
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a total lunar eclipse
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a) Several constellations are shown in more than one season. Which observation is true?
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Constellations move in a westward direction from one season to the next.
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b) What best describes the pattern described in the previous question?
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Earth's position moves eastward from one season to the next.
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The Celestial Sphere
a) From what location is it possible for an observer to see the entire Celestial Sphere? |
the equator
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b) Observers at latitudes of 20 degrees north and 20 degrees south both will see exactly the same view of the Celestial Sphere.
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true
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a) What is true about the stars on the celestial sphere?
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They are all different distances away.
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b) What is true about the celestial sphere?
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It was once believed to represent reality.
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c) What is true about astronomers?
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They use the celestial sphere, a scientific model, to explain motions of the stars.
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a) Which of the following is true for modern constellations?
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They are located in the southern sky because the southern regions of the world were explored morerecently.
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b) Which of the following is true for most modern constellations?
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They are composed of dimmer stars, because the brighter stars were already included in constellations a long time ago.
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a) From what location is the north celestial pole not visible?
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Anywhere in the southern hemisphere.
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b) From what location is the south celestial pole not visible?
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Anywhere in the northern hemisphere.
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c) From what location is the celestial equator not visible?
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Actually, the celestial equator is visible from all locations on Earth.
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Why does the sun move relative to the stars as observed from Earth?
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It is due to Earth revolving around the sun.
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Seasons
a) The minimum/maximum temperatures for any location are reached on the solstices. |
False
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b) Which factor does NOT contribute to the low temperatures in Antarctica?
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For most of the year, it is farther from the sun.
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During a total lunar eclipse, the moon is which of the following?
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A reddish color and in Earth's Umbra.
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Imagine that Earth did not turn on it's axis.
a) What would be true about the ecliptic? b) What would also be true? |
a) It would still be defined and could be seen from all points on Earth, but only when they faced the sun.
b) The day would be the same length as the year. |
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a) To predict an eclipse, it is necessary to have knowledge of which of the following?
b) The amount of time between two solar eclipses visible from the same location is about: |
a) the saros cycle
b) 54 years |
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When it is autumn in Asia, what season is it in Antarctica? (click link)
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Spring
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Lunar Phases
a) By approximately how many degrees does the moon's position change from one day to the next? b) The full moon is never visible at noon? c) In the animation, Earth's rotation is not illustrated. If Earth did not rotate, how would our view of the moon differ? |
a) 13 degrees
b) True c) The moon would almost appear to hold still during the course of a 24 hour day, only moving 1/28th of a full circle around us. |
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a) What magnitude star is greatest?
b) The answer to part A can be confusing because of which of the following? |
a) -1
b) A more negative magnitude number means a brighter star. |
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a) Which of the following is true for the celestial poles?
b) Which of the following is true about the celestial equator? |
a) The poles are the points on the celestial sphere directly above Earth's poles.
b) It is visible from all locations on Earth. |
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The postage stamp below shows the constellation Orion. Why would Orion look odd to residents of the northern hemisphere?
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Orion appears upside down.
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Which statement below most accurately describes modern constellations?
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They are 88 well defined regions on the celestial sphere.
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Based on this figure, in what constellation is the sun on July 1 each week?
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Gemini
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a) a star's Greek letter designation tells you which of the following?
b) A star with an ancient Arabic name is which of the following? |
a) its absolute brightness.
b) a relatively bright star |
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What is responsible for the observed motion of a star along the celestial equator?
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Earth's rotation on it's axis.
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Rotation of the sky
a) For Northern Hemisphere observers, at what compass point does each object reach it's highest altitude, or distance from the horizon? b) The stars seem to move across the sky together, maintaining their positions relative to one another. Why? c) For an observer at the North Pole, what would the star trails look like? |
a) South
b) All the stars are so far from Earth that we cannot perceive their individual motions. c) A dome of concentric circles, that appears as straight horizontal lines at the horizon. |
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The apparent visual magnitude of star A is 2 and the apparent visual magnitude of star B is 1. Based on that information which statement below must be true?
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Light output and distance cannot be determined from a star's apparent visual magnitude alone.
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a) Use the figure below to rank the following objects from brightest to dimmest:
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Brightest:
Full Moon Venus Sirius Polaris at dimmest |
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b) Rank the following objects in the figure from dimmest to brightest:
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Dimmist:
Polaris Sirius Venus Sun at brightest |
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c) Use the figure to rank the magnitude difference between the following pairs of objects (or magnitudes) from the biggest difference to the smallest difference:
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Biggest:
Naked eye limit/ Hubble space telescope limit Sun/ Full Moon Venus/ Polaris Venus/ Sirius |
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a) Why are winter days colder than summer days?
b) What is another reason for winter days being colder that summer days? |
a)The sun is up for less time in the winter.
b) the sun is higher in the sky in the summer. |
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a) Rank the lunar phases shown in the order that they appear during a month
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first phase:
waxing crescent first quarter waxing gibbous full moon at last phase |
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Rank the lunar phases shown in the order of the time of day the moon will rise in each phase:
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first phase:
waxing crescent first quarter waxing gibbous full moon at last phase |
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Rank the lunar phases shown in the order of the of the night you will see the moon in each phase:
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First phase:
full moon waxing gibbous first quarter waxing crescent |
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The five naked-eye planets and three telescopic planets that wonder among the stars in the sky are always near which of the following?
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Ecliptic
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What part of the sun is visible during the "peak" of a total solar eclipse?
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corona and chromosphere
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Look at the phases of the moon diagrams and visualize yourself on Earth looking at the moon.
a) Which lunar phase would be visible in the sky at dawn? b) Which lunar phase would be visible in the sky at dusk? c) Which lunar phase would be visible in the sky at noon? d) Which lunar phase would be visible in the sky at midnight? |
a0 third quarter
b) first quarter c) new moon d) full moon |
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The apparent visual magnitude of four stars are listed below. Of these four stars, which one appears dimmest in the sky?
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+2.8
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Why is the amount of solar heating less on a clear day in January at northern latitudes than on a clear day in July?
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Both the sun ia above the horizon for less than 12 hours in January in the north and at low sun angles, the received sunlight is spread over a larger surface area.
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Lunar Eclipse
a) During a lunar eclipse, what is the correct ordering of celestial bodies? b) The moon appears darkest when it passes into which part of the Earth's shadow? c) Why does the moon turn red during a lunar eclipse? |
a) Sun, Earth, Moon
b) The umbra c) Scattering of blue light in the Earth's atmosphere. |
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Why does the number of circumpolar constellations depend on the latitude of the observer?
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As an observer moves away from the equator, towards the north or south pole, there are more constellations that the rotation of the earth does not ever block his or her view throughout one full rotation.
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A total solar eclipse occurs when the moon is which of the following?
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at new phase and near ecliptic
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The postage stamp below shows a crescent moon in a starry sky. What is wrong with the depiction of the moon in this picture?
****END CHAPTER TWO--------------------**** |
The point's crescent always point away from the sun, so the sun should be visible in the sky.
****END CHAPTER TWO--------------------**** |
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Center of Mass
a) What condition must be necessary for both stars or bodies to share a common orbital path? |
They must have the equal masses.
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b) Two stars in a binary system may sometimes be found on same side of the center of mass.
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False
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c) Do two co-orbiting bodies have equal velocities?
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Sometimes- when their masses are equal.
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What does Kepler's second law indicate about the orbital speed of a planet?
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A planet moves at its fastest when it is closest to the sun.
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What of the following is true for an object moving in a circle at a constant speed?
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The acceleration is not zero, and there must be a force acting on the object in the same direction as the acceleration.
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Which feature of Aristotle's model of the universe was included in the model proposed by Copernicus?
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uniform circular motion.
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Which of these two figures matches the phases of Venus observed by Galileo?
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figure b (right)
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Kepler's Laws
a) A planet moves fastest in its orbit b) According to Kepler's first law, the orbits of the planets are what shape? c) In order to sweep out equal areas in equal times, a planet |
a) when it is closest to the Sun.
b) Ellipses c) must change its speed throughout its orbit. |
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Why did the model of the universe proposed by Copernicus gain support soon after publication?
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It was a more elegant explanation of retrograde motion.
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Galileo made several important telescopic discoveries.
A) How did Galileo's telescopic discovery of craters on the moon contradict Ptolemaic theory? |
It showed that a heavenly body was not perfect.
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b) How did Galileo's telescopic discovery of the moons of Jupiter contradict Ptolemaic theory?
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It showed that not everything orbited Earth.
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c) How did Galileo's telescopic discovery of sunspots contradict Ptolemaic theory?
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It showed that a heavenly body was not perfect.
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d) How did Galileo's telescopic discovery that Venus went through the same cycle of phase as the moon contradict Ptolemaic theory?
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It was possible in Copernican theory, but not in Ptolemaic theory.
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Epicycles
a) In which of these situations can retrograde motion be observed? |
Both
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b) Viewed from the surface of a planet, an observer is likely to see one of the moons that orbit the planet exhibit retrograde motion?
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False
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c) Which of these are characters of retrograde motion?
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A planet apparently reverses direction from its orbital path.
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WHEN Tycho observed the new star of 1572, he could detect no parallax. Why did that result undermine belief in the Ptolemaic system?
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The star is further away than the moon and thus the heavens are not perfect and unchanging.
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How did Kepler's first law of planetary motion alter Copernican system?
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It changed the perfect circles to ellipses and it placed the sun at one focus of each orbit.
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Who taught that the Earth is stationary and at the center of the universe with the sun, the moon, and the planets moving around Earth in perfect circles?
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Aristotle (384-322 BC)
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According to Newton's laws, how does the amount of gravitational force exerted on Earth by the sun compare to the amount of gravitational force exerted on the sun by Earth?
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The amount of force exerted on the sun by Earth is the same as the amount of force exerted on Earth by the sun.
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Newton's cannon
a) What is the orbital velocity due to gravity just above the Earth's atmosphere? |
7.9 km/s
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What would you expect the orbital velocity for the oon to be?
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7.9 km/s
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Once escape velocity is reached, continuing to increase velocity has no effect on the trajectory object.
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False
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Plato proposed that all heavenly motion is which of the following?
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both circular and uniform
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Why did Newton conclude that some force had to pull the moon toward Earth?
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all of the below
(*The moon's orbital motion is a curved fall around Earth. * The moon has an acceleration toward Earth. * The force and acceleration in Newton's second law must have the same direction. * The moon has an acceleration toward Earth and the force and acceleration in Newton's second law must have the same direction) |
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How was Tycho Brahe able to make more accurate astronomical measurements than had been made before his time?
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He designed and used large devices to measure small angles.
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Which of the "First Principles of Ancient Astronomy" did Kepler's laws contradict?
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Both Earth is at the center of the universe and all heavenly motion is uniform and circular.
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Which of Kepler's laws of planetary motion is a consequence of the conservation of angular momentum?
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The planet-sun line sweeps out equal areas in equal intervals of time.
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How did Nicolaus Copernicus account for the retrograde motion of the planets?
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Inner planets orbit the sun faster and pass outer planets as they orbit around the sun.
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How did Claudius Ptolemaeus account for the retrograde motion of the planets?
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Each planet moves on an epicycle that in turn moves on a deferent that circles around Earth.
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One of the first principles of ancient astronomy is that the heaven's beyond --------- are perfect, and the Earth is corrupt.
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the moon
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Newton's Laws
a) An ice skater glides forward effortlessly due to which of these Laws? |
Newton's first law
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How is force related to acceleration?
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It is proportional to the mass.
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If you push on a wall, how hard does the wall push on you?
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The wall pushes back exactly as hard.
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Which statement below best describes the difference between your mass and your weight?
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Your mass is a measure of the amount of matter that you contain and your weight is is a measure of the amount of gravitational pull that you experience.
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Gravity is a force that acts without contact between objects.
a) What is it called when a force acts on an object without contact? |
a) action at a distance
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b) What is another force besides gravity that acts without contact?
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both electricity and magnetism
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a) What is the assertion or conjecture that must be tested?
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a) a hypothesis
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b) Which is a system of rules and principles that can be applied to a wide variety of circumstances?
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b) a theory
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c) Which is a theory that has been refined, tested, and confirmed so often that scientists have great confidence in it?
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c) a natural law
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d) Which represents an unchangeable truth?
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d) none of the above
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Geosynchronous Orbit
a) What is the Radius to be used in the Orbital Velocity calculation for a Geosynchronous orbit? |
42,250 miles
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Is it possible to place a satellite in geosynchronous orbit at a much lower altitude?
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No, it can't be done
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In astronomical timescales, tidal forces between the Earth and Moon are pushing the Moon to a higher orbit. How is that affecting the moon's orbital velocity?
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*it's staying the same
*it's increasing *it's decreasing (not sure of this answer) |
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Consider the life work of the following scientists
a) Rank the scientists chronologically in the order of the dates of their birth: |
Earliest:
Ptolemy Copernicus Tycho Galileo Kepler at the latest |
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b) Rank the scientists chronologically in order of the dates of their deaths:
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Earliest:
Ptolemy Copernicus Tycho Kepler Galileo at the latest |
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c) Rank the scientists chronologically in order of the dates of their contributions to astronomy:
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Earliest:
Ptolemy Copernicus Tycho Kepler Galileo at the latest |
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What was the most important contribution of Tycho Brahe to modern astronomy?
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Twenty years of accurate measurements of planetary positions.
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What did Newton determine necessary for the force exerted by the sun on the planets to yield elliptical orbits?
****END CHAPTER THREE**** |
The force must be attractive and the force must vary inversely with distance squared.
****END CHAPTER THREE**** |
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If you were to make a telescope using the two lenses shown here, which lens should you use for the primary (objective) and which for the eyepiece?
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One uses top lens for the eyepiece and bottom lens for the primary.
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a) Which reason to build a large radio telescope also applies to optical telescopes?
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a) better resolution
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b) Which reason for building a large telescope applies to radio telescopes?
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b) long wavelength light
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c) Which reason to build a large radio telescope does not apply to optical telescope?
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c) *poor resolution
*low intensity light *actually, none of these reasons to build a large telescope apply to optical telescopes ___Not Sure of answer______ |
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Which is true about an object launched from Earth into an "open" orbit?
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Since it is still in a type of orbit, it is not necessarily traveling faster than its escape velocity.
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In which device do astronomers take advantage of chromatic aberration?
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the prism
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What can radio telescopes do that optical telescopes cannot?
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Find the location of cool hydrogen gas and see through dust clouds.
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The entire electromagnetic spectrum can be divided into seven bands: radio, microwave, infrared, ultraviolet, X ray, and gamma ray (from longest to shortest wavelength). To which of these two bands is Earth's atmosphere the most transparent?
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visible and radio
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In this figure you can see the different wavelength of light are refracted (bent) by different amounts. Which wavelengths are bent by the greatest amount?
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short wavelengths
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What is the purpose of the colors in a false-color image?
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To indicate areas of different intensity in an image.
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The visible part of the electromagnetic spectrum can be divided into seven color bands: red, orange yellow, green. blue, indigo, and violet (from long to short wavelength).
A single photon of which of these colors has the greatest amount of color? |
violet
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Radio telescopes are often connected together to do interferometry. What is the primary problem overcome by radio interferometry?
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poor resolving power.
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a) Why do nocturnal animals usually have large pupils in their eyes?
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To gather more light, so they can see better at night.
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b) Which is NOT an advantage of a larger telescope objective?
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A larger objective gives higher magnification.
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Why do radio telescopes have such poor resolution?
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because radio waves have such a long wavelength
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Which power of a large ground-based optical telescope is severely limited by Earth's atmosphere on a cloudless night?
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resolving power
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Why do the pupils of a cat's eye open wider at night?
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To increase light gathering power
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What do the newer light-sensitive electronic CCD chips do better than the older photographic plates coated with light-sensitive chemicals?
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They have greater sensitivity to light.
They can detect both bright and dim objects in a single exposure. Photometry can be done with CCD images. |
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Which would NOT be an advantage of an observatory built on the surface of the moon?
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always night
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a) Rank the following colors of visible light in order of increasing wavelength:
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Least:
blue green yellow red at the greatest |
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b) Rank the following colors of visible light in order of increasing frequency:
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Least:
red yellow green violet at the greatest |
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c) Rank the following types of electromagnetic radiation in order of decreasing wavelength:
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greatest:
radio infrared visible ultraviolet gamma-ray at the least |
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a) Which is NOT a type of electromagnetic wave?
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sound
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b) Which is something that all electromagnetic waves have in common?
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speed
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b) Which is NOT a reason to not classify sound as an electromagnetic wave?
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its wavelength is too short
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Astronomers are both hindered and assisted by chromatic aberration. In which device is chromatic aberration a big problem for astronomers?
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the primary lenses of of refracting telescopes
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a) Which is NOT an advantage of building a telescope mirror thin?
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a) Thinner mirrors are less subject to atmospheric distortion.
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b) Which could be a disadvantage of a thin or "floppy" telescope mirror?
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They tend to sag under their own weight.
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Why must telescopes observing in the far infrared be cooled to low temperatures?
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If not cooled, the telescope will give off more infrared radiation than what it is observing.
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Which power of a telescope might be expressed as "0.5 seconds of arc" ?
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resolving power
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Why must far-infrared telescopes be cooled to a low temperature?
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To reduce interfering heat radiation emitted by the telescope.
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a) Which is NOT a good reason for putting an optical telescope on a mountain?
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a) closer to space
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b) Which is the reason that radio telescopes are often put in valleys?
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b) interference
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c) Which is NOT a cause of interference for radio telescopes?
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artificial radio signals, TV transmissions, automobile ignition systems (all of the above ARE causes of interference with radio telescopes.
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What advantage do the builders of large telescopes today have over the previous generation of telescope builders?
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don't have this answer
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Refractors and Reflectors
a) In which design is the path of the light most directed? b) The image viewed viewed in any telescope is adjusted so that it is oriented "right side up" |
a) Refractor
b) False |
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Which theoretical power of an optical telescope is determined by the diameter of the primary mirror or lens?
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light gathering power and resolving power
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Why have no large refracting telescopes been built since 1900?
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all of the below**
Refracting telescopes suffer fro chromatic aberration, Making large glass lenses without interior defects is difficult, Refracting telescopes have several surfaces to shape and polish, Large glass lenses are more difficult to support than large mirrors. |
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a) What is the cause of the distortion shown in image A?
b) How was image A corrected to give image B? |
a) Earth's atmosphere
b) with adaptive optics |
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Of the two telescopes shown here, which allow you to see dimmer objects?
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The telescope on the left (bigger one)
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a) Which type of telescope is more expensive?
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for the same objective, refractors
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b) With limited funds, which type of telescope would be your choice?
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A reflector, because it is less expensive than the same size refractor, and can be made larger than a refractor.
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c) Which is NOT a reason to choose a reflector over a refractor when building a large telescope with limited funds.
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the same size reflectors are cheaper to make than refractors.
Refractors cannot be made larger than about a meter across. Reflectors do not suffer chromatic aberration. (all of the above) |
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What is a disadvantage of radio telescopes compared to optical telescopes?
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all of the below-----
Radio photons have lower energy, thus radio waves have low intensity. Interference from nearby sources of radio waves. Poor resolving power. Radio photons have lower energy, thus radio waves have low intensity and interference from nearby sources of radio waves. |
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The image below is a x-ray image of an exploded star. The colors in the image are:
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false colors that represent areas of different intensity within the image.
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Which power of a telescope is the least important?
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magnifying power
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Why are the sources of cosmic rays difficult to locate?
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Cosmic rays are charged particles, thus their paths are curved by magnetic fields, which masks the location of their source.
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Telescope mirrors have a reflective coating on their front surface as shown here. What major problem would be introduced if the reflective coating were beneath the glass surface?
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There would be some chromatic aberration.
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What do large diameter, gently curved convex (thicker in the middle) lenses and large diameter gently curved concave (thinner in the middle) mirrors have in common?
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They both have long focal lengths and can be used as primary light collectors for a telescope.
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Why are near-infrared telescopes located on mountaintops and ultraviolet telescopes in Earth's orbit?
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The primary infrared blocker, water vapor, is mostly in the lower atmosphere and the primary ultraviolet blocker, ozone, is located high in the atmosphere, far above mountaintops.
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a) Rank telescopes designed for the following specific types of electromagnetic waves in order of the maximum altitude at which they would be useful:
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Least:
radio visible infrared x-ray at the greatest |
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b) Rank telescopes designed for the following specific types of electromagnetic waves in decreasing order of the altitude at which they would be useful:
****END OF CHAPTER FOUR**** |
Greatest:
ultraviolet infrared visible radio at the least ****END OF CHAPTER FOUR**** |
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Why do hot stars look bluer than cool stars?
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The wavelength that a star radiates the most energy is inversely proportional to the temperature.
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What heats the chromosphere and corona to high temperatures?
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fluctuating magnetic fields from below that transport energy outward
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What is responsible for the sun's surface and atmospheric activity?
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the sun's magnetic field
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The nebula shown in the figure below will produce a(n)______ spectrum.
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emission
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a) Which layer is considered the "surface" of the sun?
b) Why can't you see deeper into the photosphere? |
a) the photosphere
b) The upper photosphere blocks the light from the deep photosphere. |
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a) Which are is of super-hot gas that extends farthest from the sun?
b) To which of these are sunspots NOT related? c) Which is the hottest part of the sun? |
a) Corona
b) The sun's magnetic field, Areas of lower temperatures on the Sun's surface answer: none of the above. c) core |
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If you observe that the lines of a certain element are not present in a spectrum, what can you conclude?
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It could be due to the temperature of the star.
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Which subatomic particle has a negative charge?
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electron
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Which of the following statements is true about the Celisius and Kelvin (absolute) temperature scales?
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The size of one degree is the same on both scales.
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Doppler shifts in the wavelengths of stellar spectra can tell us about the motions of a star?
a) If the lines in a stellar spectrum are blueshifted, which of the following is true? b) If the lines in a stellar spectrum are redshifted, which of the following is true? c) If the lines in a stellar spectrum show no Doppler effect, which of the following is true? |
a) The star is moving toward us.
b) the star is moving away from us. c) The star could be moving perpendicular to a line between Earth and the star. |
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What conditions produce a dark (absorption line) spectrum?
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light from a continuous spectrum source passing through a cooler low-density gas.
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What evidence do we have that sunspots are magnetic?
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The spectral lines of sunspots are split by the Zeeman Effect and observations at far ultraviolet show material arched above the sun's surface fro one sunspot to another.
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a) The image at the top is of a solar:
b) The image on the bottom is of a solar: c) What are the objects in these two images? |
a) filament
b) prominence c) they are the same |
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Kirschoff"s Laws
a) Describe what an absorption spectrum looks like b) The light bulb here serves as the blackbody. Which of these are characteristic of blackbodies? c) A star has an emission spectrum, since it is a blackbody surrounded by a thinner atmosphere. |
a) A continuous spectrum with specific colors of light missing
b) they are very hot c) False |
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How can the Doppler Effect explain wavelength shifts in both light and sound?
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The Doppler effect is produced when the source and observer of a wave are moving relative to each other, regardless of the type of waves produced.
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How constant is the solar constant? That is, by how much has the solar constant of 1360 joules per square meter per second been observed to vary over days or weeks?
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0.1%
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Why is the binding energy of an electron related to the size of its orbit?
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The closer two oppositely charged particles are to each other, the stronger the Coulomb force of attraction, and hence the stronger the binding energy. Therefore, electrons that are closer to the nucleus are more tightly bound than electrons farther from the nucleus.
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Which of the following is true of an atomic nucleus?
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Xxx all of the below (correct answer)
It contains more than 99.9% of an atom's mass. It contains all of an atom's positive charge. It contains no electrons. It contains more than 99.9% of an atom's mass and all of an atom's positive charge. |
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The wavelength of maximum intensity that is emitted by a black body is which of the following?
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inversely proportional to temperature
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Consider the figure below.
(a) The above image was recorded in which of the following? (b) The above image was recorded by which of the following? (c) The above image is of which of the following? |
a) extreme ultraviolet
b) the SOHO spacecraft c) solar prominences the chromosphere active regions Xxx all of the above ( correct answer) |
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What does a Maunder butterfly diagram show?
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During the 11 year sunspot cycle, the spots begin at high latitude and then form progressively closer to the equator.
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The spectrum of the corona has bright spectral lines of highly ionized elements. What does this reveal?
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The corona is a very hot, low-density gas.
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Explain why ionized calcium can form absorption lines, but ionized hydrogen cannot.
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Ionized calcium has remaining electrons capable of absorbing photons, whereas ionized hydrogen has no electrons.
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The Doppler Effect
(a) Light and sound waves from a moving source are ________ in the direction of movement. (b) The light or sound waves from a moving object increase in frequency when (c) What does an observer moving at the same speed with a sound source measure? |
a) compressed
b) it us moving toward an observer c) There is no change in wavelength or frequency |
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How are astronomers able to explore the layers of the sun below the photosphere?
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By measuring and modeling the modes of vibration of the sun's surface.
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What is the source of the sun's changing magnetic field?
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The differential rotation of the sun and convection beneath the photosphere.
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What is the difference between an isotope and an ion?
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An ion is an atom that has lost or gained one or more electrons. Isotopes are determined by the relative number of neutrons they have compared to the number of protons.
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a) Rank the following layers of the solar atmosphere in order from the outermost to the innermost: chromosphere, corona, photosphere
(b) Rank the following layers of the solar atmosphere in order of increasing temperature: chromosphere, corona, photosphere. (c) Rank the following layers of the solar atmosphere in order of increasing wavelengths of their peak-emissions: chromosphere, corona, photosphere. |
a) outermost : corona
chromosphere innermost: photosphere b) least: photosphere chromosphere greatest: corona c) least:corona chromosphere greatest: photosphere |
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What determines the wavelengths of the photons an atom will absorb or emit?
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the difference in energy between electron energy levels
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Which active feature in the sun's atmosphere, seen from a different point of view, corresponds precisely to the dark filaments that are observed with a hydrogen alpha filter?
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Prominence
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(a) What type of energy transport is occurring just below the photosphere?
(b) What is the evidence in the photosphere of the type of energy transport occurring beneath it? (c) What is the reason that the evidence in question A suggests the type of energy transport in question A? |
a) convection
b) granulation c) These features are cooler at their edges and hotter at their centers. |
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What are the general trends in temperature and density from the photosphere to the chromosphere to the corona?
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The temperature increases and density decreases.
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The temperature of a gas is a measure of which of the following?
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average motion of its atoms
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(a) How does a blacksmith judge the temperature of a heated piece of iron?
(b) Which piece of iron is hottest? |
a) by its color
b) blue |
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What kind of spectrum does a neon sign produce?
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Emission
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Of the following, which color represents the lowest surface temperature for a star?
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Red
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You research the star Sirius and find that its spectral lines are blue-shifted. What does this tell you about Sirius?
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It has a radial velocity that is toward us.
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Why do different atoms have different lines in their spectra?
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Different atoms have different lines in their spectra because different elements have different energy levels for the electrons.
The total number of protons, neutrons, and electrons that the individual atom contains determines the electrons energy levels; therefore, the number of protons, neutrons, and electrons determines where the energy levels are to be for the atoms and these energy levels control the energies of the transitions that can occur. |
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(a) Rank the following layers of the solar interior in order from the outermost to the innermost: convective zone, core, radiative zone.
(b) Rank the following layers of the sun in order of increasing temperature: convective zone, core, radiative zone. |
a)outermost: convective zone
radiative zone innermost:core b) least: convective zone radiative zone greatest: core |
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**********END CHAPTER FIVE***********************
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**********END CHAPTER FIVE***********************
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