Lecture 12 Please print out the pictures on Slides: 6, 11, 12, and 24.

How do the Sun, Moon, and Earth interact to create different observable features from the Earth?

Why is it warmer near the equator than the poles?

Sunlight hits the equator at a nearly straight angle while near the poles sunlight arrives at a steep angle. This is why the it is warmer near the equator than near the poles.

Why is it warmer in the summer than the winter?

Earth’s Tilted Axis The imaginary line that passes through Earth’s center and the North and South poles is Earth’s axis. Earth’s axis is always tilted at an angle of 23.5 degrees from vertical.

Video Earth’s Tilted Axis If Earth’s axis were straight up and down, temperatures in any area would remain fairly constant year-round…..There would be no seasons!

How do tides change from high tide to low tide? First of all…….what are tides? The rise and fall of ocean water that occurs about every 12.5 hours.

The force of gravity pulls the moon and Earth (including the water on Earth’s surface) toward each other. Tides are caused mainly by differences in how much gravity from the moon and the sun pulls on different parts of Earth.

So…….how does this work? Two big bulges of water form on the Earth: one directly under the moon another on the exact opposite side As the Earth spins, the bulges follow the moon.

Gravitational Effect of the Sun Neap Tides Earth, Moon, and Sun form right angles High Tides are lower and Low Tides are higher than normal Spring Tides Earth, Moon, and Sun are lined up High Tides are higher and Low Tides are lower than normal

Phases of the Moon What are the “phases of the moon?” Diagram from Fred Espenak, may be found along with lots of good information at http://www.mreclipse.com/Special/SEprimer.html

The different shapes of the moon you see from Earth! Phases of the Moon The different shapes of the moon you see from Earth! What causes these??? Diagram from Fred Espenak, may be found along with lots of good information at http://www.mreclipse.com/Special/SEprimer.html

Phases of the Moon The motion of the moon around Earth!!! Diagram from Fred Espenak, may be found along with lots of good information at http://www.mreclipse.com/Special/SEprimer.html

How much of the sunlit side of the moon faces earth! What do you think determines the phase of moon you see? How much of the sunlit side of the moon faces earth! Images from http://www.lpi.usra.edu/education/skytellers/moon_phases/about.shtml In some states, young elementary students may be required in their science standards to observe the changing patterns in the Moon’s appearance. Making observations part of the classroom assignments is a fundamental part of this; the students can bring in drawings of the Moon’s appearance on paper or on paper plates, and they can be placed on the wall over a period of 1-2 months. Students can also make phases out of Oreo cookies.

Phases - Causes When the sunlight reflects off the Moon’s far side, we call it a New Moon When the sunlight reflects off on the Moon’s near side, we call it a Full Moon Between New and Full, we see parts of the daytime side of the Moon. It is not appropriate for very young students to try to master the reason for phases; they often do not have the ability to imagine the three-dimensional nature of this. Many adults have fundamental misconceptions regarding the reason for the Moon’s phases. We conduct an activity with golfballs and blacklights in our workshop here, allowing participants to see “phases”.

New Moon During the new moon phase, the side of the moon facing Earth is not lit. As the moon revolves around the Earth, you see more of the lit side of the moon, unlit you see all of the lit side It is not appropriate for very young students to try to master the reason for phases; they often do not have the ability to imagine the three-dimensional nature of this. Many adults have fundamental misconceptions regarding the reason for the Moon’s phases. We conduct an activity with golfballs and blacklights in our workshop here, allowing participants to see “phases”.

From http://starchild. gsfc. nasa Full Moon rises as the Sun sets. The Full Moon is in mid-sky at Midnight. Full Moon sets as the Sun rises. Full Moon cannot be seen during the day.

Phases of the moon (Click) Also from StarChild: http://starchild.gsfc.nasa.gov/docs/StarChild/questions/phases.html

Eclipses What are Eclipses? When an object in space comes between the sun and a third object it casts a shadow on that object causing an eclipse. Diagram from Fred Espenak, may be found along with lots of good information at http://www.mreclipse.com/Special/SEprimer.html

There are two types of Eclipses 1) Solar Eclipses 2) Lunar Eclipses

How do Eclipses differ from Phases of the moon? Solar Eclipses When the Moon’s shadow covers part of the Earth Only happens at New Moon How do Eclipses differ from Phases of the moon? Diagram from Fred Espenak, may be found along with lots of good information at http://www.mreclipse.com/Special/SEprimer.html

Photo of a Total Solar Eclipse Video From http://sunearthday.nasa.gov/2006/multimedia/gal_008.php http://sunearthday.nasa.gov/2006/multimedia/gal_008.php

Occurs at a full moon when Earth is directly between the moon and the sun.

Occurs at a full moon when Earth is directly between the moon and the sun. Video

Exit Ticket 1. Not all planets experience a change of seasons. What causes the seasons on Earth? The changing position of the Moon in relation to Earth’s hemispheres The angle of Earth’s hemispheres in relation to the Sun Differing quantities of light coming from the Moon Changes in the distance between Earth and the Sun 2. The gravitational attraction between the Earth and Moon causes the tides. Which of the following best describes the points on the Earth where tides occur? High tides occur on the surface of the Earth facing the moon, low tides occur on the surface of the Earth away from the Moon. Low tides occur on the surface of the Earth facing the moon, high tides occur on the surface of the Earth away from the Moon. High tides occur on the near and far surfaces of the Earth, relative to the moon. Low tides occur on the surfaces of the Earth that are perpendicular to the Earth and Moon. Low tides occur on the near and far surfaces of the Earth, relative to the moon. High tides occur on the surfaces of the Earth that are perpendicular to the Earth and Moon.   3. Draw a diagram showing OR describe the difference between how a full moon and new moon are formed.