MOVEMENT OF THE EARTH

THE EARTH MOVEMENT
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We’ll be looking at the movement of the earth, this is to show that the earth moves in two way dimensional form which are Rotation and Revolution. This post also comprises the effects of these earth’s movement.
The earth move in two distinct ways, that is ROTATION and REVOLUTION. This two movement has various effects. The earth rotates on its axis and revolve round it.

ROTATION OF THE EARTHimage source
What is Rotation ? According to English dictionary, Rotation can simply be refer to as The act of turning around a center or an axis or The turning of a body on an axis which passes through its center.
The earth rotation can be defined as its movement on its axis.
The earth rotates on its axis from west to east (on an anticlockwise direction) that is once in every 24hours through 360 degree. The rotation of the earth causes day and night, this is why it is said that there are 12hours of light and 12hours of day night
However, this division does not occur at all time in all place, it rotates 15 degree in 1hour or 1 degree in 40minutes

EFFECTS OF EARTH ROTATION

1. Day and Night
2. Deflection of wind and ocean current
3. Apparent sunrise and sunset
4. Daily rising and falling of tides
5. Time different from place to place
6. Dawn and twilight
   WEST EAST ROTATION
7. Day and Night : The rotation of the earth produces day and night. As the earth rotates, only one part of the earth surface facing the sun receive the ray of the sun and experience day light [DAY] while the other part of the earth backing the sun rays will experience darkness.
8. The Deflection of Wind and Ocean current : The earth’s rotation causes deflection of wind and ocean current to the right, that is, in a clockwise direction in the northern hemisphere. In the same vein, it also causes the deflection of wind and ocean current to the left that is anticlockwise direction in the southern hemisphere.
9. Apparent Sunrise and Sunset : The rotation of the earth moves from west to east causes the apparent sunrise and sunset. It’s apparent in the sense that inhabitants of the earth surface sees the sun rising in the east and setting in the west
10. Daily Rising and Falling of Tides : During rotation of the earth, it result in the rising and falling in the level of water in the sea and ocean. Owing to the rotation of the earth the tides producing force to the surface of water turbulently [move repeatedly from one position to another] resulting in the rising and falling in the level of after in the sea and ocean
11. Time Different from Place to Place : The earth rotates through 360 ° in every 24 hours which means that for every 1 hour, is pass through since the earth move from west to east, it mean or for every 15 ° the east is always one hour ahead of time while the west is always one hour behind the time.
12. Dawn and Twilight : Dawn refers to the brief period between sunrise and full daylight while Twilight is the brief period between sunset and complete darkness. Dawn and Twilight which are result of earth rotation are caused because the earth received diffused or reflected light from the sun while it’s below the horizon.

EARTH REVOLUTION
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The movement of one body around another is geographically termed revolution. Revolution of the earth is the movement of the earth along its elliptical orbit around the sun, once in every 365¼ days or a speed of 30 km/seconds. The earth moves or revolves around the sun on its orbit. The revolving earth is tilted at an angle to the plane of elliptic during its revolution.
It takes earth 365¼ days to complete one revolution. The revolution of the earth leads to four seasons in a year. The ¼ days is added up every four years and this result to leap year. Normal year has 365days and leap year has 366 days. The earth revolves round the sun in an elliptical orbit, during this movement, the earth is permanently tilted at an angle of 66½ degree of the earth’s orbital plane.

EFFECT OF THE REVOLUTION OF THE EARTH

1. Marking of the Years : Each complete revolution around the sun mark the year, the earth takes 365 ¼ days to revolve round the sun. Since ¼ of a day cannot be recorded in a calendar, the year is normally taken as 365 days and every fourth year is given 366 days and called leap year. That extra day is usually recorded as 29th and children born on that day have the opportunity of celebrating their birthday only once in every four year
2. Changes in the season : In tropical areas like West Africa, including Nigeria there are two seasons which are Rain season and Dry season but in temperature countries the revolution of the earth causes four seasons which are Winter, Spring, Autumn, and Summer
3. Varying length of days and Night and different time in a Year : The length of day and night varies depending on the position of the earth in relation to the sun. In the northern hemisphere during winter around December 22nd as we go northwards the hours of darkness increases at the attics circle 66½° North the sun never rise and there is darkness for the whole day [December 22nd].
   In the northern hemisphere during Sumner around June 21st, the period of hours of daylight increase as we go towards north poles. At the artic circle (66½,°N), the sun never set by June 21st and there is a complete twenty four hours period of continuous daylight and this region (Artic circle) at this time is called The land of mid day night sun.
   In the southern hemisphere, one period of darkness increases towards the circle in June 21st, but the region experience winter.
   CHANGES IN ALTITUDE OF MID DAYS SUN
   As a result of the earth’s revolution the altitude ( height) of the mid day sun changes resulting in equinox and solistice
   A. EQUINOX : This is the time when the mid day sun is directly overhead at the equator, the equinox occur on march 21st and September 23rd. Equinox means there is equal day and equal night on March 21st and September 23rd. There is twelve hours of daylight and twelve hours darkness. March 21st is called spring equinox while September 23rd is called Autum equinox
   B. SOLISTICES : This is the time when the in is vertically over headed at the tropic of cancer or and tropic of Capricorn. The solistices occurs on December 22nd and June 21st. The Solistices literally means the period of day and night is not equal. On June 21st the sun is over head at the tropics of cancer resulting in June or summer solistices. This means that the northern hemisphere will have its longest day and shortest night. On December 22nd, the sun is over head at the tropics of Capricon resulting in December or winter solistices which means that the south hemisphere will have longest day and shortest night. The tropics of cancer and tropics of capricon mark the limit of the over head sun.

Here are some differences between Rotation and Revolution

1. The earth rotates on its axis while its revolves round the sun along its orbit
2. Rotation causes day and night while revolution causes season
3. The earth rotates through 360° in 24 hours[one day] while its revolves round the sun in 365¼ days [ one year]
4. The rotating earth is inclined at an angle of 23½° along its axis while the revolving earth is tilted or inclined at an angle of 66½° to the plane of ecliptic.
5. Rotation causes different of one hour between two meridians – 15° apart while revolution causes changes in the altitude of the mid day sun.

REFERENCE :
Dr. Adekolurejo>[ Adeyemi college of Education, ondo]
Dr. Adebola [Adeyemi college of Education, ondo]
Prof Fatoba [university of Ilorin]
College library, Adeyemi College of Education, ondo.
Osun State school of science library, Ile-Ife.