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. The Copernican Model: a. What 2 features of the Ptolemaic model led Copernicus to suspect that the model was incorrect? b. According to Copernicus, what do the planets orbit around, what is the shape of their orbits, and do they move at constant or non-constant speeds through space? c. d. e....

. The Copernican Model: a. What 2 features of the Ptolemaic model led Copernicus to suspect that the model was incorrect? b. According to Copernicus, what do the planets orbit around, what is the shape of their orbits, and do they move at constant or non-constant speeds through space? c. d. e. In the Copernican model, what are the 3 components of Earth's motion? What was Copernicus' correct explanation for retrograde motion? In the Copernican model, when do planets appear to slow down and increase their brightness, and why? Does this match what we observe in the sky?. g. What was Copernicus' correct order of the planets? In the Copernican model, what is the explanation for the different motion of Mercury and Venus compared to Mars, Jupiter and Saturn? The Ionian Philosophers: a. Why is Thales called one of the "original scientists"? According to legend, what celestial event did Thales successfully predict in order to prove his philosophy? b. Describe (very generally) the features of Anaximander’s cosmology and how it explained some of the cycles of the sky. 3. The Pythagoreans: a. b. What was Pythagoras proposing when he called the Universe a "cosmos"? What did Pythagoras propose about the shape of planetary orbits? What did he propose about the shape of the Earth? c. Describe 3 observations that support the Pythagorean hypothesis about the shape of the Earth. 4. Philolaus, Herakleides and Aristarchus: a. What did Philolaus believe about the Earth? What did this belief explain about the sky? b. What did Herakleides believe about the Earth, and what caused him to propose a different theory than Philolaus’? What did Herakleides believe about the motion of Mercury and Venus, and why? c. What two measurements are Aristarchus famous for? Combining these measurements, what did he correctly conclude about the relative sizes and distances of the Sun and Moon? What did these conclusions lead Aristarchus to propose about the known Universe?5. Apparent Planetary Motion: a. What is meant by apparent planetary motion?9. Claudius Ptolemy: a. What was the Latin name of the definitive Astronomy textbook written by Ptolemy in roughly 150 CE? b. Is the Ptolemaic model geocentric or heliocentric? What was the purpose of Ptolemy's 'equant point', and where is it located? Why does the equant point conflict with the Aristotelian view of planetary motion? Why did the Ptolemaic model become widely accepted, despite having violated one of Aristotle's fundamental principles? What was Ptolemy able to explain by establishing 2 different rules that attached the motion of the planets to the Sun? d. What wrong assumption about space led Ptolemy to underestimate the size of our visible planetary system (i.e. out to Saturn)? What was the importance of his measurement, despite being an underestimate?b. Describe the 3 features of apparent planetary motion discussed in the lecture. 6. Plato and Eudoxus: a. What was Plato's view on the scientific method? b. What were the two beliefs of Plato's about the celestial bodies that directed the objectives of the next generations of ancient Greek astronomers? c. According to Eudoxus, what do the planets reside on in space? Explain why a planet required 4 rotating spheres to explain its motion. 7. Aristotle: a. Explain the thought experiment, attributed to Aristotle, that was taken as "proof" that the Earth is fixed. b. In Aristotle's cosmology, what body is at the centre? c. According to Aristotle, what is everything in the terrestrial realm composed of? How did Aristotle explain the cause of motion in the terrestrial realm? d. According to Aristotle, what is everything in the celestial realm composed of? What are the qualities of this material? e. Whose model did Aristotle use to explain the motion of the planets? In this model, what are the shapes of the planetary orbits, and do the planets have constant or non-constant speed through space? f. How did Aristotle explain the daily motion of the sky? g. What was Aristotle's explanation for the source of all motion in the celestial realm? h. Why did Aristotle believe that comets are atmospheric phenomena? 8. Apollonius and Hipparchus: a. Describe the components of Apollonius' epicycle model. Is this model geocentric or heliocentric? Is all motion constant and circular in this model? b. How does Apollonius' epicycle model explain retrograde motion, the planets' changing brightness and their changing apparent speed? c. Which feature of the Antikythera Mechanism suggests that it was constructed to predict the motion of the celestial bodies using Hipparchus' model? d. What is the difference between a sidereal year and a solar year? What observation led Hipparchus to discover the precession of the equinoxes? e. How does precession affect our view of the Sun relative to the stars? Introduction to Ancient Greek Astronomy: a. According to historians, what was it about the ancient Greek empire that made it possible for theories about natural science, and astronomy in particular, to progress further than in other ancient civilizations? b. b. What does a geocentric cosmology refer to? How about a heliocentric cosmology? How would each cosmology explain the daily cycle of the Sun and the stars? 2. Use this to explain why our zodiac signs are gradually changing. f. How does precession affect our pole star? Use this to explain why the Ancient Egyptians constructed a shaft in one of their pyramids which pointed to the star Thuban. g. Explain (briefly) how it was determined that the Farnese status of Atlas is holding a celestial globe constructed using Hipparchus' lost star catalogue. 1. The Dark Ages: a. Explain why the knowledge of the Ancient Greeks gradually became inaccessible to scholars during the Dark Ages. b. What is the example provided in the lecture which demonstrates the lack of knowledge about the sky during this time period? 2. The Rise of Islamic Astronomy: a. Describe how the knowledge of the Ancient Greeks was preserved during the Dark Ages. Why were Islamic scholars interested in the astronomical knowledge of the Ancient Greeks? b. c. Why is Ptolemy's astronomy textbook known as "The Almagest"? What can we tell about the star “Alpha Centauri” based on its name, and who named the stars in this format? d. Why are the names of bright stars typically Arabic in origin? Describe one of the examples provided in the lecture or reading material. 3. Early Renaissance Astronomy: a. b. What was the importance of Regiomontanus’ translation of The Almagest? Whose cosmology did the medieval Church adopt, and why? Was it geocentric or heliocentric? c. How did Buridan's thought experiments about moving objects on Earth pave the way for heliocentrics like Copernicus? 4 5. Copernicus’ De Revolutionibus: a. When Copernicus compared the orbital periods of the planets with their orbital radii in his heliocentric model, what did he find? b. What is the (shortened) name of Copernicus' famous book in which he presented his heliocentric cosmology? c. What did Copernicus' colleague add to the book in order to make it appear less controversial? What important purpose did this preface serve in the decades following the book’s publication? 6. The Early Observations of Tycho Brahe: a. What planetary event did Tycho Brahe witness in 1563? Describe what causes this event and how it appeared in the sky. What did this event motivate Tycho to do, and why? b. What discovery did Tycho make about the supernova of 1572 ("Tycho's Star"), and how did it contradict Aristotelian beliefs about celestial bodies? Is "Tycho's Star" still visible without a telescope? How can we tell today that a supernova really did occur in the Cassiopeia constellation? c. What sort of observations did Tycho make from his observatories on the island of Hven, and why were these observations so valuable? 7. Tycho’s Search for Stellar Parallax: a. What is parallax? Describe how parallax would affect a photograph of a stop sign if you took the photograph from two different locations. b. Describe how parallax affects our view of the stars. Can we see stellar parallax with the naked eye? Why/why not? c. Explain (very generally – no calculations necessary) why Tycho’s search for stellar parallax led him to believe that the Earth is motionless. d. What is the definition of an 'Astronomical Unit'? 8. The Tychonic System: a. b. Describe the motion of the Sun, Moon, stars and planets in the Tychonic system. Does the Tychonic system explain the 3 features of apparent planetary motion? Why/why not? c. Explain how Tycho’s observations of the Great Comet of 1577 led him to conclude that the crystal orbs do not exist. Why did this conclusion make the Tychonic system more believable? 9. Kepler’s Cosmographic Mystery: a. What astronomical connection did Kepler make during one of his lectures when he drew a triangle with an inscribed and circumscribed triangle? Describe the model that Kepler published in Cosmographic Mystery as a result of this realization. nb. c. Was Kepler’s model in Cosmographic Mystery heliocentric or geocentric? What were the shapes of the planetary orbits? When Kepler compared his model to the Copernican model, why did Kepler become convinced that his own model was correct? 10. Kepler’s Search for the Driving Force of Planetary Motion: a. b. What did Tycho hire Kepler in order to prove? Why did Kepler accept Tycho’s offer? In Gilbert's book On The Magnet, what was his correct explanation for why compass needles always point to the Earth's North geographic pole? c. After reading On the Magnet, what did Kepler conclude about the cause of planetary motion? 11. Kepler’s 1st and 2nd Laws: a. Explain why Kepler’s theory about the driving force of planetary motion led him to conclude that the speeds of planets cannot be constant. b. c. What is it about the planet Mars that led Kepler to the true shape of planetary orbits? What is Kepler's 1st Law? What is location at each of the focus points in a planetary orbit? d. What is the 'semimajor axis' of an ellipse? What does the 'eccentricity' of an ellipse refer to? What is the eccentricity of a perfect circle? e. f. g. What does 'perihelion' and 'aphelion' mean? Describe the speed of a planet according to Kepler's 2nd Law. Why does Mars experience a large change in speeds compared to Earth? 12. Kepler’s 3rd Law: a. Kepler represented the orbit of each planetary in our solar system as an ascending and descending series of music notes. Why is this? b. Describe the connection that Kepler made between the spacing of the planetary orbits and musical intervals. c. What does Kepler's 3rd Law tell us about the relationship between the orbital periods of planets and their distance to the Sun? d. What are the Rudolphine Tables, who wrote them, and whose planetary model are they based on? How does their accuracy compare to the tables made using the other available models? 1. Introduction to Mayan Astronomy: a. What 2 features of the Pyramid of Kukulkan tell us that the Maya had deciphered the solar cycle? b. What was El Caracol likely used for, and how do we know this? Diagram 1 Diagram 2 e. For each position in the diagram below, you should be able to determine: The solstice or equinox that each position of the Earth corresponds to, both in the northern and southern hemisphere The local time at the position of each observer The cause of seasons: a. What causes the seasons? Describe the orientation of the Earth relative to the Sun on the solstices and equinoxes. b. c. Why does direct light feel warmer than indirect light? What season does the Southern Hemisphere experience during Northern summer, and why? 8. The Sun and latitude: a. What is the latitude of the equator? What is the latitude of the North and South pole? b. Within what latitudes can an observer see the Sun directly overhead? How did these latitudes get their names? c. What are polar nights and polar days? Within what latitudes do these occur? What happens to the number of polar days and nights as you get closer to one of Earth’s poles? 9. The celestial sphere: a. Where is the zenith and what is its altitude? Where is the horizon and what is its altitude? b. What is the altitude of the Sun when it is halfway up the sky? Does the Sun’s altitude and azimuth depend on the observer's location? Explain. 10. Describing lengths in the sky: a. What is the Sun’s altitude if you can fit 3 fists in between the horizon and the Sun’s position in the sky? b. Given that the Moon’s angular length is 0.5°, what fraction of the width of your finger would span the length of the Moon? 2. Mayan Record Keeping: a. Briefly describe the origin of the belief that the world was going to end on Dec 21, 2012. b. What physical proof do we have that the Maya tracked eclipses and the planet Venus? c. What was it about the Mayan number system that facilitated their ability to find patterns in their numeric records of the events in the sky? 3. The Moon’s Phases: a. What causes the Moon's phases? b. What is a lunation? c. State the 8 phases of the Moon, in order of appearance, starting from New Moon. d. What is the difference between a waxing and waning moon? If we look at the moon on a given night, how can we tell if it is waxing or waning? e. Why are crescent moons seen primarily during the day? Why are gibbous and full moons seen primarily at night? f. On the diagram below, you should be able to determine the moon’s phases at each of the 4 positions of Earth (A, B, C, D) © Jesse Rogersong. In the diagram above, what is the Earth’s phase at positions A and C, as seen from an astronaut on the Moon? Describe how the Earth would appear to an astronaut on the Moon at positions B and D. 4. Solar and Lunar Eclipses: a. Why did many ancient civilizations believe that eclipses are bad omens as well as unpredictable? b. What is the cause of a solar eclipse? What is the Moon's phase when this happens? c. d. Describe the appearance of a total solar eclipse and a partial solar eclipse. If an observer sees a total solar eclipse, where is this observer standing? Where is an observer standing if they see a partial solar eclipse? What will the Sun look like if you are standing outside the umbra and penumbra during a solar eclipse e. What is the cause of a lunar eclipse? What is the Moon's phase when this happens? Describe the appearance of a total lunar eclipse, a partial lunar eclipse and a penumbral lunar eclipse. f. If a total lunar eclipse is seen, what is the Moon passing through? How about if a partial lunar eclipse is seen? How about if a penumbral lunar eclipse is seen? g. If an observer on the night side of Earth witnesses a total lunar eclipse, will all observers on the night side of Earth see a total lunar eclipse at the same time?. The Eclipse Cycle and the Mayan Eclipse Records: a. b. Why don’t eclipses occur every New and Full moon? What do we call the time period when eclipses can occur? On average, how many lunations are there between these time periods? Why are there always at least 1 (or 2) solar eclipses and 1 (or 2) lunar eclipses during these time periods? c. d. Why are lunar eclipses seen more frequently than solar eclipses? On the diagram in question 3, you should be able to identify the position(s) (A, B, C and/or D) at which either a solar eclipse or lunar eclipse is possible e. Describe the evidence in the Mayan Dresden codex that tells us that the Maya understood the eclipse cycle and were able to predict, for eternity, the dates on which eclipses could occur. f. Why did the Maya believe that they had occasionally prevented an eclipse by worshiping the Sun and Moon god? 6. The Cycle of Planet Venus and the Mayan Venus Records: a. What 2 characteristics of the planet Venus caused the Mayans to identify it as a special kind of star? b. What is a heliacal rise of Venus, and how does Venus appear when this occurs? According to Mayan legend, why was this event an important day of Mayan worship? c. When is Venus seen (morning or evening) during the ~8-month period after its bright heliacal rise? Is it getting brighter or dimmer, and why? Why does it disappear after this period? When it finally reappears, is it a morning or evening star? For the next ~8 months, is it getting brighter or dimmer? Why does it disappear again after this period, before its next heliacal rise? d. Look up the date of the most recent heliacal rise of Venus, and use this to figure out Venus' current appearance. Is it visible or invisible? If it's visible, is it a morning or evening star? Is it getting brighter or dimmer? If it's invisible, why is this? e. Describe the evidence in the Mayan Dresden codex that tells us that the Maya understood the Venus cycle and were able to predict, for eternity, the dates on which the appearances and disappearances of Venus would occur. 7. Babylonian Astronomy: a. According to historians, what was it about climate conditions in the region of Ancient Babylon that motivated the Babylonians to study the sky? b. Why are there so many ‘60s’ in our units for time and angle? 8. The Naming of the Visible Planets: a. For each of the 5 visible planets, what aspect of their appearance was used to choose the Babylonian/Greek god to name them for? © Jesse Rogerson9. Daily Cycle of the Stars: a. b. Why do the stars move across the sky throughout the night? Suppose we are standing on Earth’s North pole, what are the stars moving around, and where in the sky is their centre of rotation? What happens to this point if we travel toward the equator? c. When standing on the equator, how will the stars appear to move if we face north? How about if we face south? What will happen to the centre of the Southern stars’ rotation if we travel south of the equator? d. e. What objects (if any) mark the North and South Celestial Poles? In the Northern hemisphere, how can we use a star to determine our latitude on Earth? 10. Annual Cycle of the Stars: a. b. Why do we see different stars and constellations at different times of the year? How is it possible to use a star to determine when 1 year has elapsed? 11. Astronomy in Ancient Egypt: a. b. c. What was the primary motivation for studying the sky in Ancient Egypt? Why was the star Sirius used to mark the beginning of a new year? Why did the Ancient Egyptians divide the day into 24 hours? 12. Origin of the Modern Calendar: a. Why do we add a leap day every 4 years? Who incorporated this rule into our calendar, and from what civilization did he learn this rule? b. Why do we now use the Gregorian calendar instead of the Julian calendar? 13. The Zodiac: a. Where are the zodiac constellations? Why were they significant to the Babylonian astrologers? b. c. Why can we not see our astrological constellation in the month we were born? Why have our zodiac signs changed since their original definitions by the Ancient Greeks? Introduction to archaeoastronomy: a. List the cycles of the sky described in the lecture videos that have been obvious to skywatchers since ancient times. b. What is archaeoastronomy? 2. Newgrange: a. What celestial event is Newgrange aligned to? What is special about this day of the year, and the days that follow it? Describe what happens at Newgrange on this day. 3. The Sundagger of Chaco Canyon: a. What days and times of the year can the Sundagger be used to indicate? Describe what happens to the Sundagger on these days and times. 4. Stonehenge: a. What celestial event is Stonehenge aligned to? Describe what happens at Stonehenge on this day, in the 21st century. b. Why do archaeoastronomers suspect that Stonehenge's Heel Stone had a missing partner stone? 5. The Sun’s daily cycle: a. What causes the Sun to rise in the east and set in the west every day? b. Describe the Sun’s height & approximate direction (N, E, S or W) in the sky at noon, sunset, midnight & sunrise, as seen from both the northern and southern hemisphere. 6. The Sun’s annual cycle: a. What does the word "solstice" mean? How does it describe what happens to the Sun's rising and setting positions on the summer and winter solstices? b. Which day is the longest day of the year? Which day is the shortest day of the year? Describe the difference between the Sun’s path through the sky on these 2 days. Use this to explain the 2 reasons that summertime is warmer than wintertime. c. d. What are the lengths of day time and night time on the equinoxes? On the two diagrams below, you should be able to determine: the hemisphere of the Earth (north or south) that each diagram represents which daily path of the Sun (A, B, or C) corresponds to the summer solstice, winter solstice & equinoxes, and the months in which they occur. the Sun’s rising, setting, & noon position on each path the direction the Sun is travelling on each of the daily pathways