What are days, seasons and years?

  • A day is how long it takes for the Earth to spin once on its axis and a year is 365 days.

  • Each season is a period during the year linked to temperature and daylight.

  • Knowing about the seasons is essential for growing crops.

Discover how farmers need to understand the seasons in order to grow food

What is a day?

A day is 24 hours long. This is because it takes 24 hours for the Earth to spin once on its axis.

The half of the Earth facing the Sun is in daylight. The half facing away from the Sun has no sunlight and so becomes night-time.

What is a year?

A year is how long it takes to travel once around the Sun. This takes 365 days.

Explaining our seasons

The Earth's axis is tilted as it travels around the Sun, so some parts of the Earth receive more sunlight each day than others.

This changes during the year because the Earth moves about the Sun, which gives rise to the seasons.

The UK is in the top half (northern hemisphere) of the Earth. When the northern hemisphere is tilted towards the Sun it is summer in the UK.

Six months later the northern hemisphere is tilted away from the Sun and it is winter.

In Spring, the temperature and day length become longer. In Autumn, they are shorter.

Watch the video below to see how the Earth moving around the Sun changes the seasons.

As the Earth cycles around the Sun, the length of day and night change

Why is knowing about the seasons useful?

Farmers know that crops will only grow if there is enough light and if it is warm enough. So they plant seeds in the springtime as the weather is getting warmer and the longer daylight helps the plants grow over the summer.

Days, seasons and years quiz

Test your knowledge of days, seasons and years with this quick quiz.

Where next?

Discover more about this topic from around Bitesize.

What are tides?
What are forces?
How to make a scale model of the Sun and the Earth