Why do we have nighttime and daytime

Do you see that it is sometimes pointed toward the light which represents the Sun and sometimes away from the light? Hey, you've made day and night! Think about this! So, how fast does the Earth have to rotate in order to make one complete spin in 24 hours? At the equator, the Earth is rotating at a speed of about about kilometers per hour.

Good thing we human beings can't feel this motion! A site for ages 14 and up. Laura A. This is called summer time. Find out where it is daytime and where it is nighttime right now. Colour in some pictures of nocturnal animals. Try lots of different seasons games. Play a day and night simulation game. Spot animals in the dark in Night Light, an interactive game.

Make your own paper sundial. Complete a World Day and Night Workshop online to understand more about day and night. Need help? How to videos Why join? Day and night. What are day and night? It takes 24 hours for the Earth to turn all the way around rotation. That makes one day and one night. At any moment, half of the world is in daytime and half is in nighttime. The world is like a ball.

We call the top half the Northern hemisphere and the bottom half the Southern hemisphere. The imaginary line between them is called the equator. In summer the days are longer than they are in winter. In London, the longest day is about 16 hours and 39 minutes and the shortest is 7 hours and 45 minutes.

In the Southern hemisphere the seasons are the other way around. When it is summer in Europe, it is winter in Australia. Imagine celebrating Christmas on a long, hot summer day! To help us understand where we are in the world, we also split the world into right and left halves called the Eastern hemisphere and the Western hemisphere.

The world is split into time zones. Continental Europe is in the time zone to the east of Britain, so time is one hour ahead there; when it is 1pm in Britain it is 2pm in France.

On the opposite side of the world from London is the International Date Line. On one side of the line time is 12 hours behind Britain, and on the other side time is 12 hours ahead of Britain. That means that it is a different day on each side of the line. Boost Your Child's Learning Today!

Trial it for FREE today. The Earth is always spinning around — sometimes from where you stand on the Earth you can see the Sun this is the daytime and sometimes the part of the Earth where you are is facing away from the Sun so it is dark this is the nighttime. It takes 24 hours for the Earth to spin all the way around, and we call this a day.

Astronomers discovered this by observing the time it took for a star to appear in the same place in the sky the following day, and they called this a sidereal day. Although a solar day is 24 hours, not every day has 12 hours of daylight and 12 hours of night. Daytime is shorter in winter than in summer. As the Earth moves around the sun during a year, the northern half of the Earth is tilted towards the sun in the summer, making daytime longer than night.

In winter, this reverses; the earth tilts away from the sun and nighttime becomes longer. In the spring and fall, the tilt is neither toward or away from the sun but somewhere between, so day and night are more the same at these times of the year. The solstices are the positions of the Earth's orbit that mark the longest and shortest days of the year. The winter solstice in the Northern Hemisphere is the shortest day, after which daylight hours grow longer.

The summer solstice in the Northern Hemisphere falls on the longest day, after which daylight hours become shorter. The solstices can also be named for the month in which they occur. For example, the June solstice is the point in the Earth's orbit where the North Pole faces the sun. In the Northern Hemisphere, the June solstice is the longest day of the year.