The equator is an imaginary line around the middle of planet Earth. It divides the Earth into two hemispheres, the Northern hemisphere and the Southern hemisphere. It forms the imaginary reference line on the Earth’s surface from which latitude is calculated. So, the equator is the line of 0° latitude. The Earth’s circumference is maximum at the equator that is about 40,075 km. The temperatures in locations on or around the equator are usually high all around the year. The Earth’s equatorial region is mostly covered with water..
Latitude: There are several imaginary lines parallel to the equator. Latitude measures north or south of the Earth’s equator. The latitude circles the Earth in an east-west direction. These lines help to locate places on the Earth. These lines are known as parallels. A circle of latitude is an imaginary ring linking all points sharing a parallel. The parallel is measured in terms of degrees from the equator. The equator is at 0° latitude. The North Pole is at 90°N latitude and the South Pole is at 90°S latitude.
Longitude: Longitudinal lines are the vertical lines running around the Earth, meeting the North and the South Pole. These vertical lines measure east or west of the prime meridian by imaginary lines. The central point, where the longitude is 0º, is called the prime meridian which is a line travelling through Greenwich, England, from the North Pole to the South Pole. It divides the sphere into two equal parts, the eastern and the western hemisphere. These vertical lines are known as meridians. Each meridian is measured as one arc degree. The farthest point in the East measures 180ºE and the farthest point on the west measures 180ºW.
Hemispheres: Hemispheres are the equal half portion of the Earth. When we separate the Earth half way between the North and South Poles, at the equator, we can locate the Northern and the Southern hemisphere. The half fragment of the Earth, centred on the North Pole, is the Northern hemisphere and the fragment of the Earth centred on the South Pole is the Southern hemisphere. The Eastern and the Western hemisphere are located on either side of the prime meridian.
In the month of December, the Southern hemisphere is tilted towards the Sun and the Northern hemisphere tilted away from the Sun. This is the reason why the Southern hemisphere is hot in December and the Northern hemisphere cold.
