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In your model what represented the Earth, the Sun and the Moon?. Earth: You or your partner Sun: the lamp Moon: the Styrofoam ball on the stick. How much of the lighted part of the ball did you see when facing the lamp?. NONE!.
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In your model what represented the Earth, the Sun and the Moon? • Earth: You or your partner • Sun: the lamp • Moon: the Styrofoam ball on the stick
How much of the lighted part of the ball did you see when facing the lamp? • NONE!
Explain what happened to the illuminated portion of the moon after each turn. • The portion of the moon illuminated (lit) increased with each turn until the entire moon facing the Earth was illuminated. After this the portion of the moon illuminated decreased with each turn.
Light appeared on the right • After full moon shadow appeared on the right
Whether you could see it or not, how much of the ball’s surface was always lit by the lamp? • HALF OF THE MOON IS ALWAYS ILLUMINATED BY THE SUN! • We just do not always see all (or any) of this half here on Earth! http://www.opencourse.info/astronomy
Crescent Quarter Gibbous New Full Moon Pictures
Quarter Moon FYI • Quarter Moon: Half of the moon facing the Earth is illuminated But wait… if we see half the moon lit, why isn’t it called a half moon? • This is because the moon is a quarter (or three quarters) through its cycle of phases (or we see a quarter of the entire moon lit…)
Your moon model data table should look like this! http://www.nmm.ac.uk/upload/img/phases.gif
A Moonth of Phases http://radiojove.gsfc.nasa.gov
What causes the Moon's phases? • The Moon revolving around the Earth • The Moon reflecting sunlight towards the Earth.
Why we have phases: http://home.hiwaay.net/~krcool/Astro/moon/moonphase/
So, that means… • Half of the Moon is always lit, not just the portion we see • However, sometimes we only see a profile of the lit portion of the Moon. • Certain phases of the Moon result depending on its orbit, and the Moon's orbit is responsible for the phase changes we see.
And… • Since we only see the lit portion of the Moon that is facing Earth, we see a Moon phase. • There are eight phases that the moon goes through and they always occur in the same order. • The Sun's light seems to move from right to left across the surface of the Moon.
Why do we see different phases of the moon? • The moon revolves around the Earth, so the relative positions of the Earth, moon and sun cause the phases • The changing amount of the lit portion of the moon visible on Earth = Phases http://www.lpi.usra.edu/
New Moon • During a New Moon we can see NO portion of the Moon's surface that is lit. • We see only the dark side of the Moon. This typically marks the beginning of the Lunar Cycle which lasts 29 1/2 days. • The Moon is between the Earth and the Sun in its orbit.
Waxing Crescent • During the Waxing Crescent phase, we see on the right side a small sliver of the lit Moon.
First Quarter • During the First Quarter phase, we see the right half of the lit Moon. • The Moon and Earth are now "side by side" in their orbits around the Sun.
Waxing Gibbous • During the Waxing Gibbous phase, we see almost the entire right side of the lit Moon.
Full Moon • During a Full Moon, we see the entire half of the Moon surface that is lit. • The Moon is positioned behind the Earth and Sun.
Waning Gibbous • During the Waning Gibbous phase, we see almost the entire left side of the lit Moon.
Third Quarter • During the Third Quarter phase, we see the left half of the Moon lit. • The Moon and Earth are now "side by side" in their orbits around the Sun.
Waning Crescent • During the Waning Crescent phase, we see on the left side a small sliver of the lit Moon. • www.coldwater.k12.mi.us/lms/planetarium/guide/moon.html
Waxing: illuminated portion of the moon facing Earth is increasing Waxing is from the Old English weaxan meaning “to grow.” Wax on light (from new moon to full) Waning: illuminated portion of the moon facing Earth is decreasing Waning is from the Old English wanian meaning “to lesson” Wane off light (from full moon to new) Waxing and Waning
Other facts • Gibbous is from the Latin gibbosus meaning “humpbacked.” • The moon rotates on its axis once every 27.3 days, but….. • A lunar cycle is about 29.5 days—new moon to new moon.