2. CAV 100 The Solar System

3. The Sun 99% of solar system’s mass 99% of solar system’s mass Sunspots-11 year cycle Sunspots-11 year cycle Flares Flares Parts of Sun- Parts of Sun- Photosphere-disc Photosphere-disc Chromosphere-interface Chromosphere-interface Corona-solar atmosphere Corona-solar atmosphere

4. Smaller space wanderers Asteroids Asteroids Comets Comets Head-nucleus or core-frozen water & dust Head-nucleus or core-frozen water & dust Coma Coma Tail Tail

5. Meteoroids Classifications of Classifications of Meteoroid-in space Meteoroid-in space Meteor- in atmosphere Meteor- in atmosphere Meteorite-on Earth Meteorite-on Earth

6. Units of measurement Astronomical unit-average distance between sun and earth- AU- 93,000,000 miles Astronomical unit-average distance between sun and earth- AU- 93,000,000 miles Light year –distance light travels in a year Light year –distance light travels in a year Speed of light- 186,284 MPS Speed of light- 186,284 MPS Total over 5 trillion miles Total over 5 trillion miles

7. Beyond the solar system Galaxy of the Milky Way Galaxy of the Milky Way One revolution every 200 million years One revolution every 200 million years Sun’s speed-140 miles per second Sun’s speed-140 miles per second Composition of Galaxy Composition of Galaxy Stars-over 200 billion stars Stars-over 200 billion stars Gas-clouds of hydrogen Gas-clouds of hydrogen Dust Dust

8. Properties of Stars 3000 – 80,000 C 3000 – 80,000 C Red-cool star Red-cool star White- hot star White- hot star Blue-white-hottest star Blue-white-hottest star Stars powered by nuclear fusion- converts hydrogen into helium Stars powered by nuclear fusion- converts hydrogen into helium

9. Dimensions of the Milky Way Spiral shaped Spiral shaped Width-100,000 light years across Width-100,000 light years across Thickness at center-30,000 light years Thickness at center-30,000 light years

10. Other galaxies Andromeda-M-31 two million light years away Andromeda-M-31 two million light years away Discovery published by Edwin Hubble in 1923 Discovery published by Edwin Hubble in 1923 Spiral shaped Spiral shaped Width- 100,000 light years Width- 100,000 light years Billions of stars Billions of stars Local group- 20 galaxies Local group- 20 galaxies

11. Quasars Quasi-stellar objects Quasi-stellar objects Most distant yet discovered Most distant yet discovered Light emissions vary Light emissions vary