Summer solstice is the cause of the different of season on earth
Summer solstice is when the daylight is the longest which throughout the year, and in the northern hemisphere, summer solstice this year falls on the date 21 June 2012 on the previous day. Or sometimes it is when the sun is above the North or the turning point is often referred to as the Tropic of Cancer, which is a parallel line 23A ° 27 ‘in the North Equatorial (equator) of the earth. Starting from this event, the direction of sunrise / sunset will again shift to the South.
This event marked the end of spring early summer as well as in the northern hemisphere. In contrast, in the southern hemisphere, this event marks the end of autumn early winter as well.
When the incident is reminiscent of Eratosthenes, a figure of philosophy, mathematics and astronomy experts from Greece who lived about 2200 years ago who had measured the circumference of the earth with “accurate” sun shadow method between the two cities, Shine (Aswan) and Alexandria at the time summer solstice)
Summer Solstice also marks the start of summer in the northern hemisphere and the beginning of winter in the Southern Hemisphere. Summer Solstice this term is better known because of the existence of the Sun at the northernmost point of marking the course of a long day in the northern hemisphere or the shortest night of the year. At that time, the sun didn’t rise exactly in the east but a bit more to the north of the east and will go down as well further north than the west.
Due to the Summer solstice then there is a difference ever day, night and seasons. That’s why this is a major concern in terms of astronomy,