Hi,Sorry I didn’t quite get this out to you on Tuesday. These are the lecture summaries for the first four lectures. On Thursday, I will update what was covered this week.Handouts are available at http://www.astro.umd.edu/~astr101/astr101Here is the first lecture summary. Students have found the summariesmost useful if they use them to supplement the class notes. It ishelpful to look over the terms and questions because these are the thingsthat I expect you to have learned during class. (Lunar phases lab thisweek should help you increase your understanding and prepare you for thesecond homework assignment.)Past students have found it useful to define terms weekly and write outanswers to the questions. You then will have some good study aids forpreparing for exams.REMINDERS: Homework #1 late date: Feb. 13 due at the beginning of lecture–see p. 7 of syllabusAstrology Exercise is due at the beginning of discussionsection on Feb. 18 & 19–see last page of syllabusREADING that should be completed: Read pages 1-42; Study Handouts; Review your notes.LECTURE SUMMARY 1, 2, 3, 4 (1/28, 1/30, 2/4, 2/6) Important items in the syllabus were discussed. The firstassignment was to read the syllabus and complete the pink cover sheetfor 2 pts. If you haven't done this, please make sure thatyou complete this assignment.The term light year was defined. The immensity of the universe in bothspace and time and the relative tininess of our Earth should have"boggled your mind" if you had never thought about our place in theuniverse before this class. The "Powers of Ten" video was shown. Ifyou missed it or would like to see it again, the video is available forviewing in Hornbake Library, 4th floor, Non_Print Media. Ask at thedesk for "Powers of Ten" QA 342P68. Scientists use the scientific method for acquiring knowledge.The steps followed were outlined in class. Assumptions are made inscience, such as natural forces understood on Earth are universal and notheory is above modification. Scientific theories are not proven; theyare supported to varying degrees based on consistency when scrutinizedusing the scientific method. Mrs. Deming demonstrated her "faith" inthe scientific method by using the Giant Pendulum. The appearance of the sky changes depending on your location onEarth and the celestial sphere was draw for several locations on Earthusing a purple handout in lecture. Your latitude on Earth equals thealtitude of the celestial pole and this orientation of the skydetermines what you see. Circumpolar stars, like Polaris, never rise orset; they are up all the time for a College Park observer. You reviewed sky appearance in discussion this week and will do a laboratory usinga celestial sphere next week. The apparent position of the Sun changes over the course of a year.The rotational axis of the Earth is tilted at 23 ½ degrees. The positionof sunrise on the horizon at the equinoxes is due east. The sun setsdue west after 12 hours (equinox means equal night with day). FromCollege Park on the summer solstice the Sun rises in the NE and sets NWremaining above the horizon the greatest number of hours of any day(about 15 hrs.). On the winter solstice the Sun rises in the SE andsets SW remaining above the horizon for the fewest number of hours(about 9 hrs.). In the summer the Sun's path carries it higher in thesky and it shines on us more directly than in winter. During winter thesun is low in the sky and the rays are less concentrated producing aminimal heating effect. The seasons were explained. Be sure that you canexplain why seasons occur given the season and hemisphere. Example:Explain why winter occurs in the S. Hemisphere. A green handout on lunar phases and eclipses was distributed inlecture. Keep in mind that how the Moon appears to us on Earth dependson the position of the Sun (source of light) and the position of theMoon. On the handout you should fill in the appearance of the Moon,timesof moonrise and moonset, and answer any other questions. We did some ofthis in class. The viewing of only one side of the moon was accountedfor using synchronous rotation. Mrs. Deming illustrated this bypretending to be the moon. Earthshine and eclipses werealso diagramed and discussed. Slides were shown on eclipses.TERMS you should be able to use: astronomy, planet, satellite (moon),Solar System, star, galaxy, light year, universe, scientific method,hypothesis, theory, laws of nature, circumpolar,latitude, NCP, SCP, celestial equator, zenith, altitude, horizon,ecliptic, solstices, equinoxes, seasons, lunar phases, earthshine,synchronous rotation, lunar eclipse, solar eclipse, annular eclipseQUESTIONS you should be able to answer: 1. Describe the position of the Earth in the Solar System. " in the galaxy. " in the universe. 2. What is a light year? 3. How do scientists use the scientific method to acquireknowledge?4. Compare how the sky would appear to an observer at the N. Pole,equator or College Park. 5. Using a labeled diagram explain why seasons occur. 6. Make a sketch showing the positions of Sun, Earth and Moonduring last quarter moon. What time would the Moon rise and set? Whenwould you expect the Moon to rise the following night? (You should beable to answer questions like this.) 7. Why don't two eclipses occur every month? Explain. 8. Explain what earthshine is and why it occurs.Mrs.