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# Revolution rotation seasons short 2012

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### Revolution rotation seasons short 2012

1. 1. Rotation, Revolution, and Seasons of the Earth
2. 2. What is rotation in terms of the Earth and the Moon?
3. 3. RotationRotation is a spinning motionaround a central point or axis.The planet Earth rotates every 24hours on its tilted axis. We havea day and a night in each 24 hourperiod.The Moon also rotates on itsaxis, once every 28 days. That’swhy we only see one side of theMoon from Earth. (Now spaceprobes have photographed the faror dark side.)
4. 4. Day and NightThe Earth rotates, or spins, on its tilted axis once every 24 hours, so 24 hours make upa day and a night.When the Sun’s light doesn’t reach our part of the Earth, we have night. When our partof the Earth is in the sunlight, we have day.The Sun appears to rise in the east because the Earth spins in a counterclockwisedirection (if you are looking down at the North Pole), so areas to the east becomeilluminated before land farther west.
5. 5. How long is day and night?The length of daytime and nighttime vary within the 24 hour rotation.Your location on Earth and the time of year determine how long day andnight are. In winter in the Northern Hemisphere, night is long and day isshort. In summer, the opposite occurs.
6. 6. What is a revolution in terms of astronomy ?A revolution (or orbit) is the motion of one body around another. TheEarth revolves around the Sun, as do the other planets.The Earth’s revolution around the Sun takes one year or about 365 days.The Moon’s revolution around the Earth takes about one month or 28days.
7. 7. Why do Earth’s seasons occur? The Earth turns on an axis, which runs through its North and Southpoles. This axis is tilted off-center by 23 degrees. The Earth rotates onceevery 24 hours on this tilted axis. That’s why we have day and night. The Earth revolves around the sun once every 365 ¼ days. Duringthis year-long revolution, the tilt of the Earth’s axis doesn’t change itsorientation with the Sun. Therefore, different points on the globe get theSun’s light at different angles and for different lengths of daylightthroughout the year. The light heats the Earth unevenly. That’s why wehave seasons.
8. 8. When the Northern Hemisphere is tilted toward the Sun, we havesummer. When the Northern Hemisphere is tilted away from the Sun, wehave winter. When the tilt isn’t pointing toward or away from the Sun,we have spring and fall.
9. 9. The seasons are not the same all over the Earth. At the equator, thereare no real seasons because the light from the Sun hits the Earth at aboutthe same angle and for the same amount of time all year round. At thepoles, there are only two seasons, summer and winter. In summer, it islight all the time, but in winter it is dark all the time. In between the equator and the poles, there are four seasons: winter,spring, summer, and fall. But, the seasons are reversed in the Northernand Southern Hemispheres. When it is winter in the NorthernHemisphere, it summer in the Southern Hemisphere. Spring and fall arealso reversed. Northern Hemisphere Seasons
10. 10. The seasons are reversed in theNorthern and Summer Hemispheres.