The Earth

In geography, the latitude of a location on the Earth is the angular distance of that location south or north of the equator. The latitude is an angle, and is usually measured in degrees (marked with °). The equator has a latitude of 0°, the North pole has a latitude of 90° north (written 90° N or +90°), and the South pole has a latitude of 90° south (written 90° S or −90°). Together, latitude and longitude can be used as a geographic coordinate system to specify any location on the globe.
Curves of constant latitude on the Earth (running east-west) are referred to as lines of latitude. Each line of latitude is actually a circle on the Earth parallel to the equator, and for this reason lines of latitude are also known as circles of latitude or parallels. In spherical geometry, lines of latitude are examples of small circles, with the equator being a great circle.

Longitude (λ) Lines of longitude appear vertical with varying curvature in this projection, but are actually halves of great ellipses, with identical radii at a given latitude.
Latitude (φ) Lines of latitude appear horizontal with varying curvature in this projection; but are actually circular with different radii. All locations with a given latitude are collectively referred to as a circle of latitude.
The equator divides the planet into a Northern Hemisphere, a Southern Hemisphere and has a latitude of 0°.

Besides the equator, four other lines of latitude are commonly used to mark maps of the Earth. Each of these lines plays an important role in the geometrical relationship between the Earth and the Sun:
•    Arctic Circle: 66° 33′ 39″ N
•    Tropic of Cancer: 23° 26′ 21″ N
•    Equator: 0° Latitude
•    Tropic of Capricorn: 23° 26′ 21″ S
•    Antarctic Circle: 66° 33′ 39" S
Only at latitudes in the tropics is it possible for the sun to be directly overhead (at the zenith). Alternatively, only within the Arctic and Antarctic circles is it possible to have a polar night or midnight sun.

Earth (or the Earth) is 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.[note 6]
Home to millions of species including humans, Earth is currently the only astronomical body where life is known to exist.[21] The planet formed 4.54 billion years ago, and life appeared on its surface within one billion years.
The Earth's terrain varies greatly from place to place. About 70.8%[92] of the surface is covered by water, with much of the continental shelf below sea level.The remaining 29.2% not covered by water consists of mountains, deserts, plains, plateaus, and other geomorphologies.

Continents: Europe, Asia, Africa, Australia, Americas, Antarctica.
Oceans: Pacific, Atlantic, Indian, Arctic, Southern.

Highest Mountain:         Mt.Everest: 8848m
Biggest/longest rivers:     Amazon, Nile