ASTR-1010 Planetary Astronomy Day-3

3 X 5 Card Time Name (legibly)!! What is the language of Science?

Course Announcements Labs are posted on-line. It is your responsibility to print it our prior to coming to the laboratory. Clarksville Astronomy Club meeting Tuesday Jan. 7:30pm in the Sears Planetarium Begin moon observations ASAP … you’ll need them in 2 weeks. 1 st Quarter Observing – Monday Jan. 25 – 7:00pm

HOMEWORK (already) Homework Chapter 1: Due Monday Everyone Everyone should have tried SmartWorks site by now Homework Chapter 2: Due Wednesday Jan. 27 Beginning with chapter 2, you better read the text and THINK before you blindly answer questions. Homework Chapter 3: Due Monday Feb. 8 Rotating Sky SimulationRotating Sky Simulation – Due Wednesday Jan. 27 *** Warning – this will take some time to do, so don’t wait until Tuesday night to start it ***

Heliocentric Universe Anti-intellectual fervor of 5 th Century –Libraries destroyed, The Church came to power –Islamic scholars saved and translated much of the Greek philosophic work –Contact with Hindu scholars, interaction with Chinese culture and science Nicholas Copernicus ( )‏ –Aware of Aristarchus's work –Advocated the heliocentric view Tycho Brahe ( )‏ –Observational data –All done with naked eye

Heliocentric Universe Johannes Kepler ( )‏ –3 Laws of Planetary Motion 1. Elliptical orbits, Sun at one focus 2. Equal area in equal time 3. P 2 = ka 3 (P in years, A in Astronomical Units)‏

Heliocentric Universe Galileo Galilei ( )‏ –Laid foundations of modern physics Inertia (later explained by Newton's 1 st law)‏ Gravity –First to use a telescope for astronomical purposes 1. Sunspots – Sun was not a perfect surface. 2. Craters on Moon – Moon was not a perfect surface. 3. Observations of thousands of stars not visible by eye. –So stars more numerous than Tycho thought. 4. Geocentric Universe death –Four moons orbiting Jupiter –Phases of Venus

Modern Science Isaac Newton ( )‏ –1687 – Principia – precise math descriptions –3 Laws of Motion –Universal Law of Gravitation –Invented Calculus (to prove Kepler's Laws)‏ –Developed new type of telescope

Gravity 1666 – Newton –Apple & tree ==> Moon & Earth Universal Law of Gravitation –Every mass attracts every other mass through a force called gravity. –Directly proportional to product of masses. –Inversely proportional to square of distance between them.

Hallmarks of Modern Science 1. Modern science seeks explanations for observed phenomena that rely solely on natural causes. 2. Science progresses through the creation and testing of models of nature that explain the observations as simply as possible. 3. A scientific model must make testable predictions about natural phenomena that would force us to revise or abandon the model if the predictions do not agree with observations.

Modern Science The Scientific Method. –Observations –Question –Hypothesis –Prediction –Test –Revise/More Predictions

Modern Science OR The Eureka Moment. –Look at Nature in a “general way” not looking for anything in specific –Galileo –Voyager 1, 2 - Europa Must overcome “personal experience” –Gravity doesn't “work” because of drag.

Modern Science Occam's Razor –William of Occam ( )‏ –K.I.S.S. Verifiable Observations –UFOs vs. Einstein Theory of Relativity Science, Nonscience, Pseudoscience Objectivity Scientific Theory –Newton, Darwin, Einstein

Concept Quiz – World View Which of the following would be a scientific way of viewing nature? A.All ideas are equally valuable and should be equally respected. B.Well established ideas should never be checked or tested. C.Nature informs us about the usefulness of our ideas.

Science Is a Process Science is a method for learning about nature. The scientific method works like this: –Ideas are tested against nature. –Tests come from observation or calculation. –The tests falsify some ideas and support others. All scientific knowledge is provisional.

A Scientific Result: We Are Stardust Our bodies contain many types of atoms. Except for the hydrogen in water (H 2 O), all the atoms were made in stars. Stars generate energy by making heavier elements out of light ones. They eject the material into space. New stars and planets (and humans) form out of the ejected material.

Astronomy and mathematics are closely linked Pythagoras 569 – 475BC “The underlying Structure of the Universe is Mathematical”

Science and Mathematics Science discovers patterns and rhythms in nature. Most phenomena work regularly and predictably. Mathematics is the language of patterns. Mathematics works when used to describe nature and its patterns.

Concept Quiz – Astrology as Science Astrology sounds scientific, because it uses charts and graphs and mathematics. Which of these would lead you to conclude that it is not a science? A.Astrologers cannot agree on ways of rejecting ideas. B.Astrological “energies” are not predictable. C.The Earth is viewed as having a special and unique place in the universe. D.All the above.