Overview Of HOU-TRA Workshop Presentation On Using Scientific Models In Astronomy The Following PPT Outlines A Simple Classroom Activity Using Models To Determine Some Properties of The Earth And The Attempts To Link The Simple Models To Using Complex Models & Modeling In Galaxy Evolution Credit To Joe Heafner for the simple modeling activity My version of Joe Heafner’s Modelling Activity Should Be Attached to These Proceedings, All Problems With It Are Stictly My Doing. Galaxy Crash Lab Available at thanks to Chris Mihos, Case Western Reserve University

Models in Astronomy

“My goal in life is to get through teaching without ever having an original idea” Kevin McCarron

THE Master of Low Tech in Astronomy Education Alan Gould

Credit to Original Creator of Activity Joe Haefner

What is…… The Internal Structure Of The Sun? A Cepheid Variable Star? A Neutron Star? A Quasar? Changing About Cosmic Expansion?

How Do You Know? Have You See One? Have You Touched One? Do You Take It On Authority? What Is Your Evidence?

Scientific Method?

Experiments Independent Variables Dependent Variables Controls Constants Blah, Blah, Blah……but what about astronomy?

Astronomy Often Called An “Observational Science” Really A Modeling Science Match Data to Models To Arrive At Conclusions But how often do we do that in the classroom, even the astronomy classroom?

Wiki-Def = Modeling Modeling refers to the process of generating a model as a conceptual representation of some phenomenon. Typically a model will refer only to some aspects of the phenomenon in question, and two models of the same phenomenon may be essentially different, that is in which the difference is more than just a simple renaming.

More Wiki-Def A model is evaluated using a utility function to yield estimates of several values: Ability to explain past observations Ability to predict future observations Ability to control events Cost of use, especially in combination with other models Refutability, enabling estimation of the degree of confidence in the model Simplicity, or even aesthetic appeal

Huh?

Simple Introduction to Models in Astronomy Erathosthenes & Circumference of Earth How did he know Earth was round? Can determine this with simple models & match to observations

Four Conditions To Test Near Sun, Flat Earth Far Sun, Flat Earth Near Sun, Round Earth Far Sun, Round Earth

Simple Materials Small piece of cardboard = “Flat Earth” Styrofoam ball = “Curved Earth” Light bulb = “Sun” Two toothpicks Metric ruler Protractor String

Make Predictions Of Shadow Patterns A. Some Background Here Earth B. Activity Also Asks To Make One Shadow to Disappear

Predictions Near Sun, Flat Earth? Far Sun, Flat Earth? Near Sun, Round Earth? Far Sun, Round Earth?

After Using Models & Light Source 1. Confirm, reject predictions 2. Confirm Far Away Sun by Sticks Stuck in Ground ***MATCHING MODEL TO ACTUAL DATA 3.Give Them History of Eratosthenes’ Method To Confirm Round Earth 4.Students have to use to his method to get circumference of model Earth

So We Can Arrive At Conclusions About The Nature Of The Solar System Through Models And We: Did Not Physically Measure The Sun or Earth Did Not Do Traditional Experiment

So What? We Know Earth is Round Its Just Some Old Dead Greek Guy

Why do galaxies have shapes they do? Spirals? Ellipticals? Irregulars? New Research suggests galaxy interactions are important

Galaxy Crash Lab

Modeling Change Number of Stars Angle Mass Friction From Dust, etc Dark Matter Halos

Is This A Valid Model? Does it explain past observations? Does it predict future observations? Does it give the ability to control events? Is it refutable? Is it simple?

Summary A Simple Activity Done Early In The Year Gives Students A Mental Reference Point to Relate to New, Abstract Concepts & Objects Students Must Understand That New Models May Compete & Replace Each Other Based Upon New Data NEVER Stop Discussing The Evidence & HOW WE KNOW