Earth Moon and Sun Interactions

1. Earth Moon and Sun Interactions

2. Lunar and SolarEclipses • A lunar eclipse occurs when the Earth passes between the Moon and the Sun, and the Earth's shadow obscures the moon or a portion of it. • A solar eclipse occurs when the Moon passes between the Earth and the Sun, blocking all or a portion of the Sun. A total solar eclipse is when the moon blocks out the Sun entirely. • Videos: • http://m.youtube.com/watch?v=JybXE7hXpZA&feature=related • http://m.youtube.com/watch?v=tIE1MTGz4eI

3. Lunar Eclipse Solar Eclipse Solar Eclipse Lunar eclipse

4. Moon Phases • The different shapes you see of the moon are called moon phases. • The phase of the moon you see depends on how much of the sunlit side of the moon faces earth • During new moon , the side of the moon facing Earth is not lit. As the moon revolves around Earth, you see more and more of the lighted side of the moon every day, until the side of the moon you see is fully lit. • As the moon continues to orbit, you see less and less of the lighted side of the moon. About 25.9 days after the last new moon, the cycle is complete, and you see a new moon again.

5. Moon Phases • Phase 1 - New Moon - The side of the moon that is facing the Earth is not lit up by the sun. At this time the moon is not visible. •   Phase 2 - Waxing Crescent - A small part (less than 1/2) of the moon is lit up at this point. The part that is lit up is slowly getting bigger. • Phase 3 - First Quarter - One half of the moon is lit up by the sun at this point. The part that is lit up is slowly getting bigger. •   Phase 4 - Waxing Gibbous - At this time half of the moon is lit up. The part that is lit is slowly getting bigger. Waxing means to slowly get bigger.

6. Moon Phases • Phase 5 - Full Moon - The side of the moon that is lit up by the sun is facing the Earth. The entire moon is lit up at this point. •   Phase 6 - Waning Gibbous - The moon is not quite lit up all the way by sunlight. The part of the moon this is lit is slowly getting smaller. Waning means to slowly get smaller. •   Phase 7 - Last Quarter - Half of the moon is lit up but the sun. The part that we can see lit up is slowly getting smaller. •   Phase 8 - Waning Crescent - A small part of the moon is lit up at this point. It is getting smaller by the minute.

8. Videos on Moon Phases • http://m.youtube.com/watch?v=nXseTWTZlks • http://m.youtube.com/watch?v=2aFGNGEcDOk • http://m.youtube.com/watch?v=FhokvJZFURg&feature=related

9. Tides • Tides= the rise and fall of water • Water rises for six hours the falls for six hours • They occur mainly because of differences in how much the moon pulls on different parts of the earth.

10. Spring and Neap Tides • When the sun and moon pull in the same direction the produce the greatest difference between low and high tide it's called a spring tide • The sun is at a right angles to the line between earth and moon, produces a tide with the least difference called a neap tide http://oceanservice.noaa.gov/facts/springtide.gif

11. Cause ofseasons • Earth has seasons because it's axis is tilted as it moves around the sun • Winter is when the axis is tilted away from the sun • Summer is when earth is tilted towards the sun • The northern and southern hemispheres have summer and winter at opposite times of the year • The seasons are not affected by the distance between the sun and the Earth

12. Solstice • On two days each year, the noon sun is overhead at either 23.5 degrees south or 23.5 degrees north. Each of these days are known as a solstice. When the noon sun is overhead at 23.5 degrees south is the winter solstice in the northern hemisphere. It is the summer solstice in the southern hemisphere. That solstice occurs on the shortest day of the year December 21 each year in the northern hemisphere. It is the longest day of the year in the southern hemisphere, June 21, this is the summer solstice.

13. Equinox • Equinoxes occur when the axis of rotation of the earth (the line form the N to S poles) is exactly parallel to the direction of motion of the earth around the sun. This happens on just two days of the year, the spring and autumn equinoxes. This means that day length is exactly the same (12 hours) at all points on the earth's surface on these days (except right at each pole, where it will be about to change from permanent light to dark, or the other way around).

14. Equinox • As the Earth travels around the Sun in its orbit, the north to south position of the Sun changes over the course of the year due to the changing orientation of the Earth's tilted rotation axes. The dates of zero tilt of the Earth's equator correspond to the Spring Equinox and Autumn Equinox. • The Autumn Equinox is the first day of the autumn season and occurs when the sun passes the equator moving from the northern to the southern hemisphere. The North Pole begins to tilt away from the sun. • The Spring Equinox is the first day of spring season and occurs when the sun passes the equator moving from the southern to the northern hemisphere. The North Pole begins to lean toward the sun again.

15. Questions • What is a solstice? • Name the first moon phase. • What is an eclipse? • Why do tides mainly occur? • What are the two types of tides? • What does a phase of a moon depend on?

16. Sources • http://www.enchantedlearning.com/subjects/astronomy/moon/Lunareclipse.shtml • http://www.weatherquestions.com/What_causes_the_seasons.htm • http://www.athropolis.com/sunrise/def-sol2.htm • http://www.moonconnection.com/moon_phases.phtml • http://home.hiwaay.net/~krcool/Astro/moon/moontides/