The Moon and the Sun

1. The Moon and the Sun

2. Our Moon on February 2, 2011 • How has the Moon changed the last week? • Is there a volunteer to draw what they saw on the board? • What shape would you predict tonight? • Does anyone know the name of this Moon phase? • Why does this change occur? • Did anyone observe the Moon at the same time each evening? • Was the Moon always in the same location in the sky?

3. Phases of the Moon • Cycle requires 29.5 days • The synodic month • Each phase depends on its position relative to the Sun as it orbits Earth

4. The Moon rises 53 minutes later each day Crescent waxing Moon sets in the west at sunset Crescent waning Moon rises at sunrise Full Moon rises in the east at sunset

5. Notice the direction of the crescent moon, waxing versus waning. • When the bright part is getting bigger, the Moon is waxing. • When it is getting smaller, the Moon is waning. • When the Moon is more than half-lit, it is called a gibbous Moon. • When the moon is less than half-lit, it is called a crescent Moon.

6. What is the name of the Moon’s phase last night? Waning crescent

7. Moon’s Formation 5.17 • A large size planet , thought to be the size of Mars, collided with Earth- 4.4 billion years ago • Heavier more dense material was held by the Earth’s gravitational pull The debris formed the moon

8. Day side of the Moon: high temperaturesNight side: very low temperatures The period (the time it takes to make one complete turn)around the axis and its revolution around Earth are the same. The same lunar hemisphere always faces Earth Surface scarred with meteor impact craters implies lack of crustal movement.

9. The sidereal month: when the Earth, Moon, and distant stars are aligned

10. The Moon’s influence on Earth

11. Seasons • The impact, set the Earth on its axis 23.5 degrees • Seasons help regulate the Earth’s temperature

12. Moon’s gravitational force influences the Earth’s tides Variations of tides is determined by the Moon’s location in respect to the Earth and Sun.

13. New moon • The Sun and Earth lie in one plane • The Moon’s orbit around Earth lies in another • The shadows of either Moon or Earth are normally avoided • Two times a year this pattern is changed. 5.2° Full moon Earth Sun

14. Lunar Eclipse, August 28, 2007 • The moon passes through the Earth’s shadow

15. February 9, 2009 • Penumbra lunar eclipse • Sketch a diagram of a lunar eclipse. Label the Sun, Moon, Earth, umbra and penumbra. Sketch a circle where a penumbra lunar eclipse would be located.

16. December 21, 2010, lunar eclipse

17. June 15, 2011, Lunar eclipse Draw a diagram showing a lunar eclipse and label with the following terms: Sun; Earth; Moon; umbra and penumbra

18. Our Star • Early people worshiped the Sun • Mid-1800s: size and distance was understood • Late 1800s: gravitational contraction • A shrinking gas cloud heats up because some of the gravitational energy is converted to thermal energy

19. Collapse of larger star: Supernova Supernova explosion creates more complex elements • Protostar heats up- fusion: H He • Star is created Formation of heavier elements

20. Why does the Sun Shine? • Einstein’s theory of relativity in 1905 • E = mc2 • E= energy • M= mass • C= speed of light(186,000m/s) • An enormous amount of energy produced from a tiny mass

21. Why Does the Sun Shine? • Fusion: Fusion: the combination of elements- increasing the atomic number

22. Life cycle of our sun

23. Where is our sun in this process? • 5 billion years old • 5 billion more years to go

24. Hydrogen fuel is exhausted in core: fusion continues in outer shell Core contracts. The contraction causes an increase in temperature.

25. Red Giant Forms: increase of energy Outer gaseous shell expands

26. In 5 billion years our sun will form a red giant star • The size will increase to include the location of the Earth’s orbit • When all fuel is consumed, gravitational force will cause collapse into a planetary nebula

27. Planetary Nebula • Collapsed expanding spherical cloud of gas Helix Nebula: planetary nebula 450 light years away

28. White dwarf is formed • No more nuclear reactions • Gravitational force will no longer pull gas into contraction • Glows because of its residual heat

29. How does the Sun maintain its size? • High temperatures and densities are in the Sun’s core • Gravitational force pulls inward • Pressure pushes outward • Gravitational equilibrium

30. The Sun’s structure • The sun is a ball of plasma- free flowing atomic particles can create and respond to magnetic fields • Different densities and temperatures of the plasma give the Sun a layered structure

31. Sun’s size • 300,000 times the mass of Earth • Diameter is 865,000 miles (Earth’s diameter, 8,000 miles)

32. Solar Activity • Sun’s surface churns with rising and falling gas • Sunspots: spots that are less bright because they are cooler • Regions with strong magnetic fields • Charged particles from the plasma follow the magnetic field lines

33. Solar Activity • Solar flares: changes in magnetic field lines near sunspots • Magnetic field lines become twisted and are unable to maintain the shape • Generating X-rays and charged particles nearly the speed of light

34. Solar Wind • A stream of charged particles continually blown outward in all directions from the Sun • Earth’s strong magnetic field protects the planet from the magnetic field • Forms the tails of comets as they move toward the Sun Magnetosphere: formed from the magnetic field, shown in blue

35. Solar Wind • Aurora: borealis (northern); australis (southern) • Solar wind particles get inside the magnetosphere • Trapped particles gain energy and are able to follow the magnetic field into the Earth’s atmosphere • Particles collide with atmospheric atoms and molecules • Collisions cause moving lights

36. Solar Eclipse: August 1, 2008

37. Moon’s shadow is never wider than 170 miles.

38. Solar eclipse, July 2009 Draw a diagram showing a solar eclipse and label with the following terms: Sun; Earth; Moon; umbra and penumbra

39. Next Solar Eclipse