2. Exploring the Universe

3. Earth and Moon  Our moon orbits us  Gravity between the moon and Earth keep it in orbit  The moon appears to change shape –due to our view of the part of the moon that is lit by the sun changing –See diagrams in text on page C85  LUNAR ECLIPSE = darkening of the moon when it passes through Earth’s shadow  TIDES = rise and fall of water in the ocean and seas caused by the gravitational pull of the moon on the Earth

4. Moon Phases  Phases = the changing appearances of the moon as seen from Earth  New Moon occurs when dark side of moon is facing the Earth  Waxing = lit side becomes visible –Waxing Crescent = 1 st thin slice of lit side –1 st Quarter = ½ of lit side or ¼ of moon’s surface –Waxing Gibbous = less than ½ but more than ¼ visible

5. Moon Phases  Full Moon = ½ of the surface facing the Earth is lit up  Waning = lit portion becomes smaller –Waning Gibbous = less than ½ but more than ¼ visible –3 rd (last) Quarter = ½ of lit side or ¼ of moon’s surface –Waning Crescent = last thin slice of lit side

6. To Review  When it appears to us that the moon is getting bigger, we call it: A.Waning B.Waxing  The 3 rd or Last Quarter of the moon is when the: A.Left side of the moon appears lit B.Right side of the moon appears lit C.Entire half of the moon we see is lit

7. The Earth’s Motion  We REVOLVE around the sun once every 365 days  We also ROTATE on our axis once every 24 hours  We tilt in a west-to-east direction  We rotate from west to east also  ½ of planet faces the sun during the rotation

8. Earth’s Seasons  When North Pole leans to sun = long days  When North Pole leans from sun = short days  = change in seasons  Why don’t days change much at Equator?  SUMMER SOLSTICE = daylight is the longest, June 21 or 22 in N. Hemisphere  WINTER SOLSTICE = shortest amount of daylight, Dec. 21 or 22 in N. Hemisphere  EQUINOX = sun is directly above the equator and hours of daylight and night are =

9. To Review  The Earth does this around the sun: A.Rotate B.Revolve  We do this on the Earth’s axis: A.Rotate B.Revolve

10. To Review  When the North Pole leans toward the sun we experience: A.Longer days B.Shorter days  T/F We experience the longest day of the year on December 21 or 22.

11. The Sun  Our most important star!  Gives us RADIANT ENERGY –White light of sunlight –Ultraviolet light (invisible) –Stored in fossil fuels – coal and oil Used to power cars Used to heat homes

12. The Sun  Made of hot gases –Hydrogen and Helium  Core is 15,000,000°C  Hydrogen atoms move so quickly in the core that they crash into one another and form helium = FUSION  This gives the sun energy  Energy comes to us as sunlight and radiant energy

13. How does the energy transfer from the core to the surface of the sun? A. Conduction B. Convection C. Radiation

14. How does the energy transfer to the Earth? A. Conduction B. Convection C. Radiation

15. The Sun  CORONA is the thin layer of gases that lie above the suns surface  We usually don’t see this  Hotter than the sun’s surface

16. The Sun  SOLAR ECLIPSE is when the moon is directly between the Earth and the sun  Sun is completely covered and we can see the corona  NEVER LOOK AT THIS WITH YOUR OWN EYES!

17. SUNSPOTS http://www.nasa.gov/mission_pages/themis/auroras/aurora_live.html http://www.nasa.gov/mission_pages/themis/auroras/aurora_live.html  Sunspots are regions of the sun with a very high magnetic field  These spots are cooler than the rest of the surface  They would appear darker than surrounding areas  # varies over a 11 year cycle http://www.nasa.gov/vision/universe/solarsystem/0723sunspots.html

18. SOLAR FLARES  Solar flares are explosions of hot gases from the sun  They occur when the sunspot cycle is at its peak  Gas particles and radiation reach our atmosphere  May result in blackout or power surge

19. SOLAR FLARES  Can cause AURORAS =  A glow or display of lights  Form when gas given off by solar flares hit oxygen and nitrogen over the North and South poles

20. To Review…  What is the layer of gases that surround the sun’s surface? A.Corona B.Flares C.Sunspots D.Auroras

21. To Review…  What type of eclipse occurs when the moon is between the Earth and sun? A.Lunar B.Full C.Solar

22. To Review…  What are the displays of light at the North and South Poles called? A.Lunars B.Flares C.Auroras D.Sunspots

23. Stars and their Classification  We will visit the following website:  http://www.kidsastronomy.com/stars.htm http://www.kidsastronomy.com/stars.htm  View from Hubble: http://hubblesite.org/newscenter/newsdesk/ archive/releases/2005/05/image/ http://hubblesite.org/newscenter/newsdesk/ archive/releases/2005/05/image/  Apollo11 http://www.nasm.si.edu/collections/imager y/apollo/AS11/a11av.htm http://www.nasm.si.edu/collections/imager y/apollo/AS11/a11av.htm

25. Back to the life cycle Black Dwarf Nova Mid-sized

26.  http://hubblesite.org/explore_astronomy/bl ack_holes/ http://hubblesite.org/explore_astronomy/bl ack_holes/