THE MOON

1. THE MOON

2. THE SURFACE OF THE MOON • It has no atmosphere, so a record of all the impacts has been preserved • We know the age of the moon, so by counting the # of impact craters they can find the rate of cratering. • Knowing the rate of cratering, scientists can use the # of craters on any body to estimate how old the body’s surface is.

3. LUNAR ORIGINS • 3 popular explanations for the moon’s origins: • 1. The moon was a separate body captured by Earth’s gravity. • 2. Moon formed at the same time & from the same materials as the Earth • 3. The newly formed Earth was spinning so fast that a piece flew off & became the moon

4. LUNAR ORIGINS • The composition of the Moon was similar to the Earth’s mantle. • Found through rock samples • Current Theory: • A large object collided with Earth, while the Earth was still forming. • This was so violent that a chunk of the earth’s mantle was blasted into orbit around the earth to form the Moon

5. PHASES OF THE MOON • Within a month it changes from a fully lit circle to a thin crescent back to a circle. • This is a result from its changing position relative to the earth and the Sun • As the moon revolves around the Earth, the amount of sunlight on the side of the moon that faces the Earth changes

6. PHASES OF THE MOON • New Moon • Waxing Crescent • First Quarter • Waxing Gibbous • Full Moon • Waning Gibbous • Last Quarter • Waning Crescent

7. NEW MOON • Moon is between the Sun and Earth and is not visible in the sky

8. WAXING CRESCENT • Lighted area appears to be growing larger • Right side of the Moon as seen from Earth is lighted.

9. FIRST QUARTER • ¼ OF THE WAY AROUND THE EARTH. HALF OF THE MOON IS LIGHTED

10. WAXING GIBBOUS • Lighted areas of the moon continues to grow. • Right side of the Moon as seen from Earth is lighted.

11. FULL MOON • Entire lighted side of the Moon is visible from Earth

12. WANING GIBBOUS • Lighted area of the Moon appears to be getting smaller. • Left side of the Moon as seen from Earth is lighted.

13. LAST QUARTER • ¾ of the way around the Earth. • Half of the moon is lighted.

14. WANING CRESCENT • Lighted area continues to grow smaller. • Left side of the Moon as seen from Earth is lighted.

15. Waxing and Waning • WAXING • The sunlit fraction we can see is getting LARGER • Waning- • The sunlit fraction we can see is getting SMALLER • The moons period of rotation is the same its period of revolution, so on Earth you always see the same side of the moon

16. How the Moon affects the Tides

17. ECLIPSES • Eclipse: • When the shadow of one celestial body falls on another

18. SOLAR ECLIPSE • When the moon comes between the Earth and the Sun and the shadow of the moon falls on part of the Earth • Annular eclipse (partial): • Moon is farther from the Earth • The disk of the moon does not completely cover the disk of the Sun • Penumbra – lighter outer part of a shadow • Total Solar Eclipse: • The disk of the moon completely covers the disk of the sun • Umbra – Darker inner part of a shadow

19. Umbra & Penumbra

20. LUNAR ECLIPSE • Happens when the Earth comes between the sun and the moon and the shadow of Earth falls on the moon. • During a lunar eclipse the Earth’s atmosphere acts like a lens and bends sunlight into the Earth’s shadow. • Most of the light you see during a lunar eclipse is red.

21. The Tilted Orbit Of The Moon • The Moon is tilted about 5 degrees relative to the orbit of the Earth around the Sun. • This is enough to place the moon out of the Earth’s shadow for most full moons and the Earth out of the moon’s shadow for most new moons

22. How the tilt affects the seasons

23. Seasons • http://www.teachersdomain.org/ext/ess05_int_seasonsgame/index.html