4 - The sun appears “in front of” just 13...

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CYCLES OF THE SUN -In addition to rising and setting every day, the sun undergoes yearly changes. -It is the sky more in summer and less in winter. -The sun rises and sets from different locations throughout the year. -This fact was carefully observed by ancient astronomers, and used to predict the Seasons SUNS ANNUAL CYCLE -The suns path through the sky varies annually. -its rising and setting directions also change. -The day it reaches greatest heights (at noon) is called the Summer Solstice - The day it reaches the lowest height (at noon) is call the Winter Solstice THE ANNUAL “MOTION” OF THE SUN -At night, we see different constellations at different times of the year. -The constellations we see are always those away from the sun. -But as Earth orbits around the sun, we view the sun from different perspectives. -If we could see the stars behind the sun, we would see it pass in front of 13 constellations. -These are called the constellation of the Zodiac . THE ANNUAL MOTION OF THE EARTH Earth revolves around the Sun
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Unformatted text preview: The sun appears “in front of” just 13 constellations (Note: you can’t see a constellation when the sun is “in front of” it)-As seen from Earth, The suns apparent path on the sky is called the ecliptic. Throughout the year, the sun appears to be “in” each of the constellations of the Zodiac All of the planets orbit the sun in the same plane. This plane is also called “THE ECLIPTIC” THE REASON FOR THE SEASONS-Hypothesis: The seasons are caused by the Earths proximity to the sun. In Summer, the Earths must be closer to the sun.-Data: When things are closer to the a light source (like the sun) they get hotter.-Data: in most of the northern hemisphere it is warmer in “summer” (June, July, and August)-but in the southern hemisphere, just the opposite is true.-Data: Earths distance from the sun hardly changes in the course of the year. (About 1 %)- (in fact, the earth is closest to the sun each year on January 4.)-Conclusion?...
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This note was uploaded on 09/24/2011 for the course SCI 115 taught by Professor Mccarthy during the Spring '11 term at S.F. State.

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4 - The sun appears “in front of” just 13...

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