Transcript Lecture 1
Lecture 1 ASTR 111 – Section 002 Introductory Astronomy: Solar System Dr. Weigel Outline 1. 2. 3. 4. Course Overview Course Logistics and Syllabus Angular Measurements Accuracy vs. Precision Course Overview Topics * Note * I will send a link to these lecture notes later today Some slides will appear in lecture that are not on your print-outs. Ashes to ashes, dust to dust. Gasses to gasses, stardust to stardust? How did the solar system form? There is a theory which states that if ever anyone discovers exactly what the universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another which states that this has already happened. Douglas Adams (1952-2001) What are the differences between planets? www.mattjonesblog.com/img/scale/SolScaleC.jpg http://www.mattjonesblog.com/img/scale/SolScaleB.jpg How does the sun interact with Earth? Why does the sun follow a certain path in the sky? http://antwrp.gsfc.nasa.gov/apod/ap071222.html Why do we have eclipses? Why are some eclipses different? http://apod.nasa.gov/apod/image/0604/eclipse2006_seip.jpg http://antwrp.gsfc.nasa.gov/apod/ap080808.html What causes the moon’s phases? Why do we have seasons? http://www.whisperedhope.com/Images/seasons%20Of%20Life%20Large.jpg Course Overview General Information • Astronomy 111 is designed to give you an overview of the solar system and the methods of astronomy. • It has been developed for non-science majors who wish to gain a better understanding of the known universe, ancient and modern astronomy, and methods for interpreting astronomical observations and measurements. • A mathematical background including high school algebra, geometry, and trigonometry is necessary to do well in this course. Course Overview How to succeed • Come to class and participate – 70% of success in life is just showing up – Woody Allen • Do the reading assignments – The reading for this week is Chapter 1 (all) and Chapter 2 (section 2.1-2.2 only). • Take the quizzes – The quiz for this week will only cover topics discussed in lecture Course Overview Key goals • I want you to understand the basic principles of astronomy • I want you to think critically – Perspective of any employer: Baseline knowledge of facts is helpful. But baseline knowledge will not help you in new and unusual situations. • I want you to be able to think like a scientist – Simplify the complex by using basic principles – Interact with other people to solve a problem Outline 1. 2. 3. 4. Course Overview Course Logistics and Syllabus Angular Measurements Accuracy vs. Precision Course Web Page, etc. • I use both Blackboard and a separate web page. • Lecture notes and syllabus: http://aurora.gmu.edu/astr111 • Quizzes: http://gmu.blackboard.com. Assigned Thursday, due Tuesday before class. • Announcements via your regular GMU email. If you do not receive an email before 10 pm tonight, send me an email at [email protected]. • You should receive an email from me every Monday and Wednesday. Step 1: Log-in Step 2: Click Assessments Exams and Quizzes • Three exams + a final exam all of equal weight • Lowest score is dropped • Quizzes count for 10% of final grade • Best three exam scores count for 30% each • Letter grades are – – – – – – – – – – A AB+ B BC+ C CD F = = = = = = = = = = 93-100 90-93 87-90 83-87 80-83 77-80 73-77 70-73 60-70 0-60 Make-up Exams No make-up exams Contact [email protected] 703-993-1361 The Office Hour • After class (Tues/Thurs 10:15-?) • By appt. (send me email) Lecture Notes • Lecture notes posted the day before class. • I will send an email to your GMU account when it is posted. • I suggest printing out the lecture notes (or at least the in-class exercises) prior to class. Do you need to take the lab? • Probably • See your academic advisor! http://www.bio.psu.edu/people/faculty/strauss/anatomy/misc/Lab%201943.jpg Textbook 8th Edition Cover 7th Edition Cover Honor Code • Student members of the George Mason University community pledge not to cheat, plagiarize, steal, or lie in matters related to academic work. http://ndn.newsweek.com/media/36/071005_SO02_vl-vertical.jpg Lecture Structure “I hear and I forget. I see and I remember. I do and I understand.” http://www.thequoteblog.com/wp-content/uploads/2007/06/confucius.jpg Attendance Outline 1. 2. 3. 4. Course Overview Course Logistics and Syllabus Angular Measurements Accuracy vs. Precision Angular Measurements • Subdivide a circle into 360 degrees 1 degree Astronomers use angles to denote the positions and apparent sizes of objects in the sky =Observer’s Zenith • Astronomers use angular measure to describe the apparent size of a celestial object—what fraction of the sky that object seems to cover • The angular diameter (or angular size) of the Moon is ½° or the Moon subtends an angle of ½°. If you draw lines from your eye to each of two stars, the angle between these lines is the angular distance between these two stars The adult human hand held at arm’s length provides a means of estimating angles Angular Measurements • Subdivide a circle into 360 degrees 1 degree • Subdivide one degree into 60 arcminutes – minutes of arc – abbreviated as 60 arcmin or 60´ • Subdivide one arcminute into 60 arcseconds – seconds of arc – abbreviated as 60 arcsec or 60” 1° = 60 arcmin = 60´ 1´ = 60 arcsec = 60” What is 0.5 degrees? • Using arcminutes and arcseconds? What is 0.5 degrees? • Using arcminutes and arcseconds? 0.5 degree 60 arcminutes 1 degree What is 0.5 degrees? • Using arcminutes and arcseconds? 0.5 degree 60 arcminutes 30 arcminutes 1 degree What is 0.5 degrees? • Using arcminutes and arcseconds? 0.5 degrees 60 arcminutes 60 arcseconds 1800arcseconds 1 degree arcminute Group Questions • Form groups of exactly 4 • Optimal configuration is two students in one row and two students in another row No Yes No http://antwrp.gsfc.nasa.gov/apod/image/0808/moongames_lavederN080717_9416.jpg Turn in one card per group … if you disagree on answer, write down what you disagreed about • • • • Name, seat #, and height Name, seat #, and height Name, seat #, and height Name, seat #, and height • Question 1 Answer • Question 3 Answer • Question 4 Answer • Question 2 Answer Front side Back side Turn in one card per group … if you disagree on answer, write down what you disagreed about • • • • Name, seat #, and height Name, seat #, and height Name, seat #, and height Name, seat #, and height • Question 1 Answer • Question 3 Answer • Question 4 Answer Me Row 1, seat N Row 1, seat 1 • Question 2 Answer Row 2, seat N Front side Row 2, seat 1 Back side A B 1. What is the angular distance between points A and B on this slide (In degrees and arcminutes). Each student should take their own measurement. 2. Predict what will happen if you made your measurement in two different parts of the room. 3. Next week you sit in the same chair but weigh 30 pounds less. Will your (angular) measurements change? 4. Do you think there will be a relationship between a persons height and the angle they measure? A B 1. What is the angular distance between points A and B on this slide (In degrees and arcminutes). Each student should take their own measurement. 2. Predict what will happen if you made your measurement in two different parts of the room. 3. Next week you sit in the same chair but weigh 30 pounds less. Will your (angular) measurements change? 4. Do you think there will be a relationship between a persons height and the angle they measure? http://antwrp.gsfc.nasa.gov/apod/ap071025.html Before you leave • Turn in cards at front of room. One card per group. • Is this a graded assignment? No.