Switch off unnessesary outdoor light at night

Do you know that light pollution is harmful to animals that need darkness? So please switch off the outdoor light that you do not need at night. This also reduces energy and will save money. So, please use your discrimination, if the outdoor light you switch on at night is really necessary. If needed, LED light has a higher efficiency than conventional bulbs. A timer helps to minimise the light to the needed duration. For more information about light pollution, also known as light smog, please read here: → National Geographics, Article Light Pollution