ABSTRACT
EACH DAY, from the moment we open our eyes, we make use of light.When we read a book, look at a screen and enjoy works of art, the beauty of flowers or a view from the mountains we are sensing light that has reached our eyes.Light travels through space across distances that are unimaginable and so we can see stars that may not exist any more. Light from the Sun is the energy source that keeps our planet alive – plants photosynthesise and provide the basis for all other life on Earth.
