* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Climate Change
Survey
Document related concepts
Rare Earth hypothesis wikipedia , lookup
Planets beyond Neptune wikipedia , lookup
Astrobiology wikipedia , lookup
Formation and evolution of the Solar System wikipedia , lookup
Definition of planet wikipedia , lookup
Geocentric model wikipedia , lookup
IAU definition of planet wikipedia , lookup
History of Solar System formation and evolution hypotheses wikipedia , lookup
Extraterrestrial life wikipedia , lookup
Planets in astrology wikipedia , lookup
Astronomical unit wikipedia , lookup
Transcript
Climate Change Entry Lesson Planetary Temperatures Activity SC.912.E.7.7 Identify, analyze, and relate the internal (Earth system) and external (astronomical) conditions that contribute to global climate change. (C) Copyright 2014 - all rights reserved www.cpalms.org 1 Essential Questions • What factors determine the average temperature of a planet? • In what ways can you describe how the earth is heated? (C) Copyright 2014 - all rights reserved www.cpalms.org http://commons.wikimedia.org/wiki/File:Thermometer_0.svg 2 Extension Question How can you relate o internal (planetary system) – and o external (astronomical) conditions of Earth’s global climate change to at least 1 of the other inner planets? (C) Copyright 2014 - all rights reserved www.cpalms.org http://wardssciencewiki.wikispaces.com/file/view/composite_earth 1_red.gif/162969781/composite_earth1_red.gif 3 Electromagnetic Spectrum • Photons: packets of energy o Have no mass o Can travel through space o Travel along wave paths (C) Copyright 2014 - all rights reserved www.cpalms.org https://www.flickr.com/groups/pilipinas/discuss /72057594124976565/ 4 Radiation can be reflected, scattered, or absorbed (C) Copyright 2014 - all rights reserved www.cpalms.org http://www.eco-info.net/what-aregreenhouse-gases.html/reflection 5 Planetary Temperature • How does the average temperature of a planet depend on its distance from the sun? • • Simple model Input: From the sun Output: Radiation of a heated object Analysis Equilibrium: Input = Output D=distance from sun, T=average temperature Create a combination of D & T that is a constant Use data to see how close each planet is to the same constant. (C) Copyright 2014 - all rights reserved www.cpalms.org 6 Design a Model to Simulate Solar Radiation (C) Copyright 2014 - all rights reserved www.cpalms.org Photo: credit: Terri Pope-Hellmund 6/16/2014 Orlando, FL FRC-STEM 7 Collect Data Model Planet Name (C) Copyright 2014 - all rights reserved www.cpalms.org Distance from Heat Source cm Equilibrium Temperature Degrees Celsius Input • Let S=total power (energy produced/time) of the sun (S ~ 4x1026 watts) • This power passes through the surfaces of all spheres of that orbit the sun with radius R centered at the sun. • • The surface area of a sphere =4πR2. • Note: Same “inverse square law” applies to gravitational Power/Area = Intensity = S/4πR2 attraction, spatial variation of sound and light intensity. (C) Copyright 2014 - all rights reserved www.cpalms.org Input Intensity = S/4πR2 (C) Copyright 2014 - all rights reserved www.cpalms.org Output • • Radiation of heat from the object Common approximation: treat the planet as a “black body”: Intensity = aT4 T: temperature (measured from absolute zero) A: constant (C) Copyright 2014 - all rights reserved www.cpalms.org Solar Input & Radiative Output (C) Copyright 2014 - all rights reserved www.cpalms.org Equilibrium: Solar Input=Radiative Output • • • • S/4πR2 = aT4 (S/4πa) = R2T4 Model Prediction: RT2 = constant (all R). Test prediction: Measure R and T for various planets and note whether the prediction is valid. • Create a bar graph showing RT2 for each planet PREDICTIONS????? (C) Copyright 2014 - all rights reserved www.cpalms.org Predict temperatures for planets Planet Name Mercury Venus Earth Mars (C) Copyright 2014 - all rights reserved www.cpalms.org Average Distance from Sun Astronomical Units .39 Average Temperature Degrees Kelvin 400 Inner Planet Data Planet Name Average Temperature Degrees Kelvin Mercury Average Distance from Sun Astronomical Units .39 Venus .72 730 Earth 1.00 280 Mars 1.52 213 (C) Copyright 2014 - all rights reserved www.cpalms.org 400 • Excel Model 450000 400000 Venus 350000 300000 250000 200000 150000 100000 50000 Mercury Earth Mars 3 4 0 1 (C) Copyright 2014 - all rights reserved www.cpalms.org 2 Closure: Planetary Temperatures 1. What determined the temperature of your planets? 2. Did your planets come to an equilibrium temperature? What is happening at that temperature? 3. If your sun got hotter, would the temperature change? How? 4. If your planet got farther away, would the temperature change? How? 5. What conclusion can you draw when analyzing your model data and the actual measurements for the inner planets? (C) Copyright 2014 - all rights reserved www.cpalms.org Inner Planets http://evansscienceblog.blogspot.com/2012/02/innerplanets.html (C) Copyright 2014 - all rights reserved www.cpalms.org 18