Earth is the third planet from the and the fifth largest. The earth orbit

is measured by 149,600,000 km from the sun. The diameter of the

earth is 12,756.3 km and mass is a wopping 5.9736e24 kg. Earth is t

he only planet whose English name doesn't derives from

Greek/Roman mythology. The name derives from Old English and

Germanic. There are, of course, hundreds of other names for the

plants in other languages. For example, In Roman Mythology, the

goddess of the Earth was Tellus.

It was not until the time of Copernicus that it was understood that the

earth is just another planet.

Earth of course, can be studied without the aid of spacecraft.

Nevertheless it was not until the twentieth century that we had maps

of the entire planet. Pictures of the planet taken from space are of

considerable importance; for example, they are an enormous help in

weather prediction and especially in tracking and predicting

hurricanes. And they are extraordinarily bueatiful.

The earth is divided into several layers which have distinct chemical and seismic properties.

(depth in km) 0-40 Crust 40-400 Upper Mantle 400-650 Transition Region 650-2700 Lower Mantle 2700-2890 D'' Layer 2890-5150 Outer Core 5150-6378 Inner Core

The inner core and crust are solid; the outer core and mantle layers

are plastic or semi-fluid. The various layers are seperated by

discontinuities which are evident in seismic data; the best known of t

he is the Mohorovicic discontinuity between the crust and upper

mantle.

Most of the mass of the earth is in the mantle most of the rest is the core. The part we inhabit is a tiny fraction of the whole.

 

(x10^24 kg) atmosphere .0000051 oceans .0014 crust .026 mantle 4.043 outer core 1.835 inner core .09675

The core is probably mostly composed of iron (or iron/nickel)

though it is possible that some lighter elements may be present too.

Temperatures at hte center of the core may be as high as 7500K,

hotter than the surface of the sun. The lower mantle is probably

mostly silicon, magnesium,and oxygen, with some iron, calcium, and

aluminum. The upper mantly is mostly olivene and pyroxene,

calcium, and aluminum. The crust is primarily quartz and other

silicates like foldspar.

The length of one day on earth is 24 hours. The lenght of one year is

365.25 days. The earth is 29% land and 71% water. The earth has

one satelite and it is called moon. One meaning for the word moon is

companion. The earth tilts at an angle of 22.5 degrees. The earth is

somewher between 4.5 and 4.6 years old. The earths atomosphere is

composed of 71% nitrogen and 22% oxygen with traces of argon,

carbon dioxide and water.

The earth is a very fascinating planet. It is the only human habital

planet and supplies sufficienct needs for the human race. I chose in

the research paper to right about some uncommonly known things

about the earth instead of the same old Hoopla.

Worked Cited

"Earth" Helicon Publishing Ltd.

1999. Pgs. 3

"Mother Planet" Helicon Publishing Ltd.

1999. Pgs. 5

"Small Blue Planet" Infonautics Corporation.

1998. Pgs. 6