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Phases of the Moon |
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WebQuest |
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Phases of the Moon
WebQuest
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THE EARTH & THE
MOON
What you see when you look at the moon depends on its location in relationship to the sun and Earth. The moon never goes away or changes shape-we just see a different fraction of sunlight being reflected from the moon to Earth.So how do you explain why this happens? Start with the facts: The moon is our planet's only natural satellite. Its diameter is about a quarter that of Earth's. The moon takes about 27.3 days (about a month) to revolve around Earth, traveling at an average distance of about 384,000 kilometers.
We divide the moon's orbital cycle into several segments, or phases. When the sun and the moon are on the same side of Earth, the sun illuminates the side of the moon that faces away from Earth. We don't see any reflected sunlight on its front face, so it looks like there is no moon. We call this the new moon phase. When the crescent moon begins to appear, if you look carefully you may see some faint illumination of the moon from earthshine. About two weeks later, when the moon and sun are on opposite sides of Earth and all are in a line, the sun shines past Earth directly onto the full face of the moon and we see a "full moon." What happens in between?As the new moon phase ends, the moon waxes, or appears to grow larger, and we see more of the moon's face. The lighted area increases over time from right to left from our perspective on Earth. When the sun-earth-moon angle is very small, we see only a thin bright curve, called the waxing crescent. Over the next seven days the angle between the sun, Earth, and the moon grows to 90 degrees. We see the sunlight spread to cover the right half of the moon. This is called the first quarter. The visible part of the moon continues to wax through the gibbous phase over the next seven days until we see the full moon.
As the cycle continues, we say the moon is waning, or growing smaller. The amount of lighted area we see decreases, and the darkened area increases from right to left. You can tell if the moon is waxing or waning by whether the right side of the moon is dark or light.
Another 14 days pass as the moon moves through the waning gibbous phase, then the third quarter, then the waning crescent phase, and seems to finally disappear in the new moon phase. Now we're back to where we started about a month ago!
After completing this activity you should understand that the observed phase of the Moon is determined by the Moon's position relative to the Earth and Sun.
1. You will use a web resource to view satellite photographs of the moon and Earth. The web site will give you pictures that show what the Earth and moon look like at exactly this day and time (This is called real time ).
2. Go to the website Map of the Earth. This map will show which parts of the Earth are in darkness and which parts are in sunlight at this moment in time.
Name a place in darkness and a place in daylight. Locate where you are on the map. Fill in the date and time on the printout page and shade the map as it appears on the screen.
3. Simply in terms of light and shadow, predict, at this moment in time, (1) what the Earth looks like from the moon, (2) what the Moon looks like from the Earth, (3) and what the Earth looks like from the Sun. Next, explore three images in real time using the websites listed below. Record what you see on the three circles at the bottom of the printout page using shading and rough outlines of the continents (for two the views of Earth).
4. Click Phases of the Moon to view: the diagram shows the Moon in different positions along its orbit around the Earth.
Moon Phases
5. Create drawings that show how and why the moon looks different as it revolves around Earth
Internet Links:Space Academy Will display Moon phases beginning on January 1st, 1990 through December 31st, 2019. Very quick. Just scroll down the page a bit, and click to the correct date (first image shown may not be correct). Phases of the Moon shows the entire month, plus has previous months archived. A View of the Moon Just type in the date in this format DD-MM-YYYY. Virtual Reality Moon Phase Pictures usable, but a little more complicated Solar System Simulator Choose a planet or satellite, and a place to stand, and the simulator will render a color image for you! The Moon Some facts about the Moon
Good Books:
by Gail Gibbons Published by Holiday House Publication date: March 1, 1997 ISBN: 0823412970
Book Description : A comprehensive, illustrated introduction to the moon for young readers provides facts about our moon, its phases, and eclipses, as well as the effects the moon has on our world, such as the pull of the tides. Identifies the moon as our only natural satellite, describes its movement and phases, and discusses how we have observed and explored it over the years.
by Isaac Asimov Published by Gareth Stevens Publication date: September 1991 ISBN: 0836804384
Book Description : Explains why the moon changes from crescent to full moon every twenty-nine and one-half days. Another great book by Isaac Asimov.
by Eric Hadley, Tessa Hadley Published by Cambridge Univ Pr (Short) Publication date: August 1, 1983 ISBN: 052125227X
Book Description : Twelve traditional tales about the sun and the moon from a variety of cultures.
Rubric
Students' have gained further understanding of day and night, light and shadow, as they apply to the sun, moon, and Earth.
