Clear your desks and get ready for the final part of your unit test.

 Go to bell-science.com  Scroll over “Earth/Environmental Science”  Scroll over “Semester 1”  Click “Unit 1 Our Universe”  Scroll to the bottom of the page and open “Unit 1 Pre- test analysis”, complete the form using your pre-test  Then open “CosmologyTest Analysis”, complete the form using your Cosmology Test Data Entry

 You will be given 15 minutes to use your notes and correct any incorrect answers. For each correction you must also explain why that answer is correct (explain the science in your own words)  You have until next Wednesday (9/24)  You may come in during  Homeroom Friday  Before school any day  After school Thurs, Fri, Mon, Tues Test Corrections

Our Sun

Universe Milky Way (spiral) Galaxy Solar System

Where are we?

 How did it form?  Basic facts  99.8% of mass  100x diameter of Earth  5,527 o C  92.1% H, 7.8% He  Plasma  Sun today Sun today  Main source of Earth’s energy Our Sun

 Definitions  Thermal energy  Temperature  Heat  Types of heat  Occur in different parts of the Sun  Core  Dense, hottest  Hydrogen fusion  Conduction How do we get the Sun’s energy?

 Radiation  Energy transfer (heat)  Light waves  Also how energy gets to Earth  Energy moves slowly  Thick layer Radiation Zone

Convection Zone  Uses convection  In liquids and gases  Material heated (conduction)  Rises….why?  Sinks….why?  Repeat  Moves more quickly in this layer

1.VideoVideo  Write down your observations  Why did that happen? Daily Review #1

 Photosphere  Visible surface  Chromosphere  Red  High speed gas  Corona  Hot  Outermost layer  Seen during an eclipse Outer Solar Structure

 Sunspots  Dark  Cold  Solar flares  High energy  Explosive  Prominence  Loops/arches Surface Feature Basics

 What is a magnetic field?  What causes a magnetic field?  On the Sun?  Effect of rotation  Different rotation rates  Magnetic field lines get wound up  Eventually snap  Causes a solar flare  Solar prominences  Follow magnetic field lines into space Sun’s Magnetic Field

 Cooler than nearby areas  Appear in pairs  Intense magnetic field  Lines go out and in Sunspots

 Hot, high speed, plasma streams  Corona expanding  Coronal Mass Ejections (CME)  Massive eruption  Rearrangement of magnetic field lines  One hit on 10/15/13  Effects on Earth  Disrupt magnetic field shape  Danger to astronauts  Damage electronics  Aurora Solar Wind

 Predictable cycle  11-years  Minimums  Last = 2008  Low # of prominences, flares and sunspots  Cooler climate on Earth  Next maximum = 2013 Sunspot Cycle

 Borealis or Australis  Interaction of particles and magnetic field  Particles drawn to poles  Colors  Elements  Altitude  Constantly changing  Video Video Aurora