1. Earth’s Moon
It takes 27.3 days for the moon to revolve around the Earth relative to a background star (sidereal month).
Because Earth also revolves around the Sun, it takes 2 more days for the moon to line up with the Earth and Sun again - (cycles of the moon, 29.5 days). Known as the synodic month.

2. How does the moon affect the Earth?
Tide: rise or fall in the ocean surface
Gravitational attraction between moon, sun, and large bodies of water
The closer the moon is to the water, the stronger the pull; water on the side facing the moon is pulled more strongly toward the moon, producing a bulge and high tides.

3. How does the moon affect the Earth?
Tide: rise or fall in the ocean surface
Gravitational attraction between moon, sun, and large bodies of water
The closer the moon is to the water, the stronger the pull; water on the side facing the moon is pulled more strongly toward the moon, producing a bulge and high tides.

4. Problem: Moon rises an average of 52. 7 minutes later each day
Problem: Moon rises an average of 52.7 minutes later each day. You can use this formula: TN = To + N x 52.7 minutes Where TN = the time of high tide in 7 days To = the original time of high tide N = number of days later for which you want to determine the high tide If the original high tide is 1:00 pm, find the time of high tide in 7 days. TN = 1:00 pm + 7 x 52.7 min = 1:00 pm min = 1:00 pm + 6 hr 09 min = 7:09 pm

5. Moonlight
The Moon shines because it reflects sunlight from its surface
As Moon orbits the Earth, different areas of the side that faces earth reflects sunlight, causing Moon’s appearance to change

6. Phases of the Moon
New Moon – Occurs when the Moon is between the Earth and Sun
After new moon, moon phases are waxing (Moon appears to grow larger)
Waxing crescent - The first phase after new moon
First quarter Moon - About a week after new moon; half of Moon is visible
Waxing gibbous – from first quarter Moon until full Moon
Full moon – when side of the Moon facing us is entirely illuminated, Earth is between Moon and Sun

7. Phases of the Moon
After full moon, moon phases are waning (Moon appears to grow smaller)
Waning gibbous crescent – from full moon to 3rd quarter Moon
3rd quarter Moon -half of Moon is visible
Waning crescent –small sliver
New moon
If 2 full moons in one month (29.5 days/one lunar cycle), then second full moon is sometimes called a blue moon

9. Solar Eclipse
When the moon moves directly between Sun and Earth and casts shadow on the Earth.
Umbra - Darkest portion of the moon’s shadow
Penumbra – lighter shadow on Earth’s surface that surrounds the umbra

10. Videos https://www.youtube.com/watch?v=NCweccNOaqo

12. Lunar eclipse
When the Earth passes between the Sun and the Moon and casts a shadow on the Moon
Begins when Moon moves into Earth’s penumbra, moving into Earth’s umbra
Can only occur when Moon enters a full moon phase
Partial lunar eclipse: occurs when a portion of the Moon moves into earth’s umbra; the remaining portion of the Moon is in earth’s penumbra and receives some direct sunlight

14. Frequency of Eclipse
Total solar eclipse: Up to twice/year, but most people don’t see it
Only those people living in small area where moon’s umbra strikes Earth can see total solar eclipse
Total lunar eclipse – more frequently observed
because all of the Moon is in Earth’s umbra, so anyone on the night side of Earth could see it

15. Moon’s Surface
Craters: depressions on the moon’s surface created by impacts from asteroids and comets
Mountains (highlands): areas that were thrust upward from the impact events

16. Moon’s Surface
Maria: surface features which are dark colored, flat, lava filled regions
Created when cracks formed in the crust from the impact of asteroids/comets, the cracks allowed lava to flow into craters and fill them

17. Moon’s Surface
Regolith: layer of dusty lunar material produced by collisions between asteroids and comets and the Moon; can be up to 40 m thick

18. Moon’s Interior Seismographs left on moon’s surface revealed Crust
Mantle
Core
Maria on Moon’s surface suggests the interior of the moon must have been molten at one time

19. Origin of Moon Giant Impact Theory:
Moon formed about 4.4 billion year ago when Mars-sized object collided with Earth
The cores of the 2 bodies combined and settled toward the center of primitive Earth
Some gas and rock thrown into orbit; remainder condensed into mass which formed moon
Explains why Earth and Moon similar, but not identical

20. Earth Evidence for Earth’s shape as a sphere
No matter where you are on earth, objects fall straight down (gravity)
Earth’s shadow on the Moon during a lunar eclipse is always curved
People in different parts of the world see different stars at night

21. Earth’s shape Gravity is responsible for Earth's shape
Astronomers think Earth formed as objects in solar system crashed into each other and combined because of gravitational attraction
Energy released as objects crashed into growing Earth to be molten
Gravity caused molten Earth to form sphere
As Earth cooled over time, different layers formed due to differences in density, becoming the inner core, outer core, mantle and crust

22. Earth’s Magnetic Field
Magnetic field: Scientists hypothesize it is the result of Earth’s rotation and the circulation of molten metals in outer core
Magnetic reversals: location of magnetic poles change over time; large-scale magnetic reversals occur on average every 200,000 years
Auroras: Sun produces solar winds (streams of electrically charged particles) The magnetosphere deflects these harmful particles, causing them to spiral along Earth’s magnetic field. They eventually collide with atoms and molecules in Earth’s atmosphere, causing them to emit light.

23. Planet Earth The orbit of Earth around the Sun is elliptical.
An ellipse is an elongated closed curve with two foci.
The distance of the Earth to the Sun varies
The Earth is closest to the Sun in January (147 million km) and is farthest away in early July (152 million km)
Planet Earth

24. Earth in the Solar System
Venus
Venus nearly same size of Earth
Atmosphere contains 96% CO2 (carbon dioxide) – Earth contains 0.04%. Earth’s oceans absorbed much of it
High CO2 creates greenhouse effect – temperatures of +460°C (Earth average is 15°C).
Mars
Slightly half the diameter of Earth; gravitational pull only 38% as strong, not strong enough to hold dense atmosphere so average surface temperature is -63°C
Mars lacks magnetic field, which allows atmosphere to be stripped away by solar wind