INFORMATION COMMUNICATION TECHNOLOGY

MICCROSOFT POWERPOINT PRESENTATION

Lawrence Andrew Fronda

BSED 1-A n

Earthis the third planet from

the Sun, and the densest and fifth-

largest of the eight planets in the

Solar System. It is also the largest of the Solar

System's four terrestrial planets. It is sometimes referred to as the world, the Blue

Planet,[20] or by its Latin name, Terra

Historical Accounts of earth

Shape and Size of the Earth

Eratosthenes became head librarian at the Royal Library around 235 BC. There, he made the first accurate measurement of the earth's circumference. His value (based on the altitude of the noontime sun as seen from Alexandria and Syrene on the first day of summer) was approximately 25,000 miles. The actual equatorial circumference is 24,902 miles.

What is the diameter of the earth?

The diameter of the earth at the equator is 7,926.41 miles (12,756.32 kilometers).

SHAPE OF EARTHNewton computed that the Earth's shape should be an oblate spheroid, a solid formed when an ellipse is rotated about its axis Expeditions to Peru in 1735 and to Lapland in 1736 confirmed this theory.

RotationThe Earth spins on its axis from West to East (counter-clockwise). It takes the Earth 23 hours, 56 minutes, and 4.09 seconds to complete one full turn. Day and night are produced by the rotation of the Earth. The speed of rotation at any point upon the equator is at the rate of approximately 1,038 miles per hour, decreasing to zero

While the Earth is spinning on its axis, it is revolving around the Sun in a counter-clockwise direction. It takes the Earth one full year to complete one full revolution around the Sun. This path is known as the Earth's orbit. It is very near a circle. The mean distance of the Earth from the Sun is about 93 milling miles and the distance varies by 3 million miles, forming a slightly oval path.

Revolution

Effects of Earths MotionSolsticesThe solstices are days when the Sun reaches its farthest northern and southern declinations. The winter solstice occurs on December 21 or 22 and marks the beginning of winter (this is the shortest day of the year). The summer solstice occurs on June 21 and marks the beginning of summer (this is the longest day of the year).

Equinoxes

Equinoxes are days in which day and night are of equal duration. The two yearly equinoxes occur when the Sun crosses the celestial equator. The vernal equinox occurs in late March (this is the beginning of spring in the Northern Hemisphere and the beginning of fall in the Southern Hemisphere); the autumnal equinox occurs in late September (this is the beginning of fall in the Northern Hemisphere and the beginning of spring in the Southern Hemisphere).

INTERNAL SRUCTURE OF EARTH

The Crust Within the crust, intricate patterns are created when rocks are redistributed anda deposited in layers through the geologic processes of eruption and intrusion of lava, erosion, and consolidation of rock particles, and solidification and recrystallization of porous rock.

crust

The Mantle

Our knowledge of the upper mantle, including the tectonic plates, is derived from analyses of earthquake waves (see figure for paths); heat flow, magnetic, and gravity studies; and laboratory experiments on rocks and minerals. Between 100 and 200 kilometers below the Earth's surface, the temperature of the rock is near the melting point; molten rock erupted by some volcanoes originates in this region of the mantle

The Core (Outer Core) The outer core of the Earth is a liquid layer about 2,266 kilometers thick composed of iron and nickel which lies above the Earth's solid inner core and below its mantle. Its outer boundary lies 2,890 km (1,800 mi) beneath the Earth's surface. The transition between the inner core and outer core is located approximately 5,150 km beneath the Earth's surface.

Inner coreThe inner core of the Earth, its innermost hottest part as detected by seismological studies, is a primarily solid ball about 1,220 km (760 mi) in radius,[1] or about 70% that of the Moon. It is believed to consist of an iron–nickel alloy, and may have a temperature similar to the Sun's surface, approximately 5778 K (5505 °C).[2]

Earths Atmosphere

The atmosphere of Earth is a layer of gases surrounding the planet Earth that is retained by Earth's gravity. The atmosphere protects life on Earth by absorbing ultraviolet solar radiation, warming the surface through heat retention (greenhouse effect), and reducing temperature extremes between day and night (the diurnal temperature variation).

The Beauty Of Earth

End Of my Presentation-GODBLESS US-