What are the Effects of UV Rays?

The Sun is Earth's main source of energy. It gives off heat and light, keeps our planet warm and makes life on Earth possible.

However, ultraviolet (UV) light from the Sun can have harmful effects. Although we cannot see UV light from the Sun, it can fade colours of paper and fabric by breaking down chemicals in coloured dye. 

It can also damage our skin cells and cause sunburns. This makes our skin very red and painful. 

This is why we need to use sunscreen to block the sun's UV rays. This prevents the UV light from reaching our skin cells.

Let's try this simple activity to find out the effects of the sun's rays!

What you need

  • Construction paper 
  • Sunscreen
  • Something heavy to hold down your construction paper
  • A sunny spot


Step by Step

1) Squeeze a pea-sized amount of sunscreen onto your hands.

2) Rub the sunscreen onto both your palms and fingers. Make sure that there is a thin layer of sunscreen spread evenly, covering your palms and fingers.

3) Press your hands firmly onto the construction paper. Make sure that your fingers and palms are in contact with the construction paper. 

4) Place the construction paper in a sunny spot and expose to the sun for 3 to 4 hours.

5) Hold the sides of the paper down with something heavy so that it doesn't fly away! (Make a prediction: What do you think will happen?)

6) After 3 to 4 hours, observe your paper. 


The colour of the paper has faded. This is caused by the sun's UV rays. The UV rays have broken down the chemicals in the coloured dye used give the construction paper its colour.

The areas that were protected by the sunscreen (the handprinted area) still have the original bold colour. Sunscreen protects us from harmful UV rays by absorbing UV light and preventing it from reaching our skin cells.

Hope you enjoyed this experiment. Remember to put on sunscreen when you know that you will be spending long hours playing in the sun! Don't miss more extension activities for the Space Exploration box. Follow us on Instagram and Facebook to get the latest updates!