Saviz Safizadeh

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The Spring Equinox

• By
• Saviz Safizadeh

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The Earth is the 3rd planet in the solar system
after the planets Mercury and Venus.
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• The Earth rotates around an imaginary line. This
  line passes through the North and the South
  poles. Scientists call this line the Earths axis
  of rotation.

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The Earth turns on its axis. This movement
takes 24 hours and is the reason behind day and
night.
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• The Earth also moves in space in a circular
  motion around the sun. Scientists say the earth
  orbits or revolves around the sun.

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• It takes the Earth 365 days or one year to
  fully orbit the sun.
• The Earth rushes through space orbiting
  the sun with a speed of 108,000 Km/hr or
  67,000miles/hr.

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• The Earths axis is tilted by 23 ½ O

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What are the Reasons for the Seasons?
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There are 2 reasons for all 4 seasonsa) The
Earths motion on its orbitb) the Earths
inclined axis
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• On the first day of Spring
•  the Sun shines directly over the Equator.
• There are an equal numberof hours of daylight
  and darkness.

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• Twice each year (March 20- 21 and September 23),
  the sun directly crosses the equator and day and
  night are equal everywhere on earth. These are
  called the Vernal and Autumnal equinox During
  
• the vernal equinox in the northern hemisphere,
  the southern hemisphere is in autumnal equinox.

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In the northern hemisphere, the summer solsitice
begins on the last day of spring as the north
pole is most tilted toward the sun.
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• The winter solstice begins on the last day of
  fall as the north pole is most tilted away from
  the sun.

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After a long, cold winter, everyone
awaits the arrival of the new season.As the
earth warms up, plants begin to grow and animals
leave their shelters.
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For humans, spring is a time of work as
well as celebrations. People have celebrated
this new day in many cultures Until 1582,
most of the Roman empire and the Medieval Europe
celebrated their new year in March.Ostara,
Nowrooz, Easter, Tel Shemesh are only some of
many celebrations of the rebirth of nature and
the renewal of life.
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Bibliography

• http//www.1ststeps.org/Science/seasons.htm,
  October 12, 2007.
• http//en.wikipedia.org/wiki/Solar_System
• http//www.ecology.com/archived-links/earths-rotat
  ion/index.html
• http//spiff.rit.edu/classes/phys301/lectures/sunm
  oon
• http//www.zoomschool.com
• http//upload.wikimedia.org/wikipedia/commons
• http//cse.ssl.berkeley.edu