At night, air becomes lighter and lighter

Light pollution is increasing.

An international group of scientists has been studying satellite images of the earth for five years. They saw that the amount of light rises by 2 percent every year. The area that is artificially illuminated also grows by 2 percent annually. The increase is happening all over the world, but especially in areas that until now were quite dark. 'Light grows fastest in places where there is not much light,' says German research leader Christopher Kyba.

According to the researchers, the switch to LED lights has less effect than expected. Although these lamps save electricity, so money, but that money is then used to place more lamps, they conclude. The findings are in the scientific journal Science Advances.