Why do we have seasons? Because of the tilt on our axis!!!!!!! NOT our distance to the sun

SUMMER WINTER

Dates to Remember

Angle of Incidence

What is the difference between rotation and revolution? Rotation = spinning around its axis Earth’s Period of Rotation = 24 hours Causes day and night (rise and set of sun, moon, and stars) Revolution = orbiting an object Earth’s Period of Revolution = 365 days 6 hours 9 min Causes yearly changes (seasons, variations in number of daylight hours) because of our tilt

Exit Questions 1. Axis A. 23.5 degrees 2. Perihelion B. closest to the sun 3. Revolution C. 1 day (24 hours) 4. Aphelion D. 1 year (365 ¼ days) 5. Rotation E. farthest from the sun 6. Tilt F. imaginary line that runs from pole to pole around which we spin

The MOON

Lunar Motions Moon Phase Cycle (Synodic Month) = 29 ½ days Moon Revolution (Sidereal Month) = 27 1/3 days Moon Rotation = 27 1/3 days Daytime Temperature = 127 degrees Celsius Night Temperature = -173 degrees Celsius

Properties of the Moon Diameter = 3,475 km (1/4 the diameter of the Earth – unusually large) Density = 3.3 g/cubic centimeter (Earth’s is 5.5) Gravity = 1/6th of the Earth Moon has no atmosphere or water

Lunar Surface Marias (seas) = dark, relatively smooth areas, ancient lava flows Regolith – layer of dust on the lunar surface that formed from the meteorite impacts Highlands = light colored, mountainous areas that are heavily cratered

Formation of the Moon Impact Theory: A mars sized object collided with the Earth The material ejected from the surface of the Earth became the Moon. This explains… Why does the Moon have a much lower density than the Earth? Why does the Moon not have any water?

Moon motion model lab Perigee – moon closest to the Earth Apogee – moon farthest from the Earth

Mimas (saturn)

Titan (saturn)

Triton (neptune)

Europa (jupiter)

Miranda (Uranus)

Io (Jupiter)

Phobos and Deimos (Mars)

Our Moon

More Moon Fun

Distance to the Moon Perigee – 221,519 miles Apogee – 252,712 miles Avg. Distance - 237,700 miles

Moon Phases Sidereal Month – moon revolution – 27 1/3 days Synodic Month (moon phase cycle) – 29 ½ days ALWAYS STARTS WITH A NEW MOON

Moon Phases The changing appearance of the moon as seen from Earth CAUSED BY…the changing position of the moon relative to the Earth and the Sun

Moon Phase Cycle

Go Over the last unit test

Do Now: Identify Each Moon Phase 1) _________________ 2) _________________ 3) _________________ 4) _________________

Moon Phase Calendar Activity

Solar Eclipse Sun-Moon-Earth Moon is 1/400 the size of the sun and 1/400 the distance to the sun making them look identical in size Umbra – complete shadow Penumbra – partial shadow

Lunar Eclipse SUN-EARTH-MOON

Tides Periodic rise and fall of sea level High Tides occur every 12 hours and 25 minutes (24 hour 50 minute cyle) Direct Tide – moon pulls the oceans toward it Indirect Tide – less pull on opposite side causes another bulge

TIDES Spring Tide – cumulative gravitational pull of the moon AND sun on our oceans. Tides are much Higher and lower than usual. Occurs every Full and New Moon

TIDES Neap Tides – occur during 1st and 3rd quarter moon phases in which the moon is at a right angle to the Earth compared to the sun. Tides are much LESS strong