1. Lecture 1: Introduction Why Astronomy is Fun The Scientific Method Group Activities in Lecture Reading: E5, Appendix 1, 2 (5 pages) Homework: WebCT Diagnostic Survey, Horoscope for Thursday’s lecture

2. Why Astronomy is Fun

12. “Mostly Harmless”

17. radio infrared

22. Syllabus Logistics Office Hours E-mail Web page http://www.physics.drexel.edu/~jca32/teaching/phys181 Book’s Web page (http://wps.prenhall.com/esm_chaisson_BG_5/)http://wps.prenhall.com/esm_chaisson_BG_5/ WebCT Text Astronomy: A Beginner’s Guide to the Universe Lectures Starting/ending Format HW & Quizzes Number/times Format Exams Grading

23. What is Science? Science – the process of distinguishing between the truth, the improbable, and the impossible.

24. Scientific Progress Most descriptions of new physical phenomena are wrong (e.g., Earth is flat) New ideas can seem “wacky” (inconceivable even) at first (e.g., Earth is round) Sometimes those wacky ideas turn out to be correct Sometimes they are not Often these ideas can be hard to test directly or can take a long time to prove/disprove New ideas become accepted theories if they are capable of making correct predictions about future events

25. The Scientific Method Observe Hypothesize Predict Test Modify The Moon has craters The Moon is made of Swiss cheese The Moon tastes like cheese Astronauts find that it tastes like rock The Moon is rocky and the craters are cause by impacts?

26. “Theories” Something that has stood the test of time. Not “just a theory”. More like a law than a hypothesis Something that has proven to be true time and time again, and is likely to be true upon further tests. “ Theory, hypothesis are used in non-technical contexts to mean an untested idea or opinion. A theory in technical use is a more or less verified or established explanation accounting for known facts or phenomena.”