ASTR 1010 Exam #1 (Sections 1.1 - 4.2) Feb 11, 2015ASTR 1010 Exam #1 (Sections 1.1 - 4.2) Feb 11, 2015-This summarizes most, but not necessarily all, topics that will be on the exam-* What are stars, planets, the solar system, a galaxy, and the universe. Milky Way-* Approximate size scales (grapefruit analogy). What are astronomical unit and light year-* What is the speed of light; understand d = v t relation-* Approx. number of stars in the Milky Way. Recognize Earth is not sitting still in space-* The observable universe. How big is it. How old is universe. How do we know this-* How are stars in a constellation related. How many official constellations are there-* Number of arcminutes in a degree. Arcseconds in a arcminute. Zenith and horizon-* Celestial sphere, celes. equator, and celes. poles. Ecliptic. Circumpolar stars-* Cause of stars’ apparent rotation around poles. Why is Polaris a special star-* Why whether a star is visible depends upon latitude and time of year-* Why do the Earth’s north and south poles have 6 months of day/night each year-* How to estimate time of day using a diagram that tells you where you are on Earth-* What causes the seasons. How much is the Earth’s tilt. Tilt is relative to what-* Why does the angle of the incoming light make a difference. the Zodiac-* Summer and winter solstices, spring and fall equinoxes. What are they. Precession-* Names for and progression of the lunar phases. Basic cause. Waxing vs. waning-* Moon’s orbital period. Why is the lunar cycle 2 days longer. Always see same side-* Relation between lunar phase and the time of day the moon is observable from Earth-* What is an eclipse. Solar and lunar types. Why sometimes partial or total-* Why are solar eclipses sometimes annular; approximate angular size of Moon and Sun-* Phase of moon required for each type of eclipse. Why are there not eclipses every orbit-* Five easiest to see planets. Why was their motion hard to explain by early observers-* Why do planets appear to exhibit retrograde motion-* Plato/Aristotle - what influence did they have on future “astronomers”-* Ptolemy - geocentric solar system model. How did it explain retrograde motion.-* Copernicus - Sun centered model; why did it not work much better.-* Tycho Brahe - precise observations; Kepler - Laws of planetary motion.-* What are Keper's 3 Laws (and what do they mean).-* Galileo - what objections to Sun-centered model did he help overcome; know 4 things-he observed with telescope to accomplish this; when did he do this (early 1600s)-* What makes something a scientific theory/hypothesis. astronomy vs. astrology.-* Speed, velocity, acceleration; what is the “acceleration of gravity”. What does it mean-* Newton’s 3 laws: constant velocity unless ... (or, inertia), F=ma, action/reaction forces-* Mass versus weight. Apparent weightlessness. Why do objects (e.g. moon) stay in