Earth and Space Science 14.7 The Sun: An Important Star

1. Grade 9 Academic Science Earth and Space Science14.7 The Sun: An Important Star

2. Quick Facts • the center of our solar system – heliocentric model. • the Sun has many different layers – each performing different activities. • the layers are composed of gases – the sun has no solid surface, however it does have structure (layers).

3. The Reactions • nuclear fusion is the process that produces energy in the Sun • the temperature and pressure are so high that hydrogen nuclei combine to form helium nuclei

4. Structure of the Sun They Might be Giants

5. The Sun’s Surface Features • Sunspots • A dark region of cool matter on the photosphere caused by a twist in the Sun’s magnetic field • Vary in size and colour • Solar Flares • Gases and charged particles that are blasted above an active region of the Sun’s photosphere • Extremely hot – tens of millions of degrees Celsius • Can cause power outages here on earth!!!

6. Sunspots and Solar Flares

7. Solar Flares – Scary and Cool!

8. Solar Winds • The Sun’s corona is constantly releasing electrically charged particles into space. • They travel at speeds of 400 km/sec and are called ‘Solar Winds.’ • Earth’s magnetic field channels these excited particles toward the poles – this results in the AURORAS

9. Auroras http://www.youtube.com/watch?v=N5utQxtma2U • coloured lights in the sky produced when solar wind comes in contact with Earth’s magnetic field and the atmosphere • known as the Northern lights when seen over the North Pole (Aurora Borealis)

10. Homework: • Read pg. 452 - 453 • Fill in the Handout • Answer #1 – 4 , 7 on pg. 453 They might be Giants