Artificial light makes night less dark; study unveils 10% brighter nights

According to a new study, the use of artificial light at night has made the night sky turn brighter in recent years. In this study, more than 50,000 observations of stars showed that the night sky has turned brighter by an average of 10% every year from 2011 to 2022.

The presence of artificial light at night is known as light pollution. Light pollution veils the night sky, making it difficult to spot stars. However, light pollution is much more of a problem than this! Light pollution can have a negative effect on natural cycles.

Too much light at night may be harmful for human health, and may make migrating birds fly into buildings. Light pollution can also disrupt food webs by making pollinating insects fly towards light instead of plants. Light pollution may interrupt the mating of fireflies!

In some sense, this new study is a call for action to prevent light pollution. According to Connie Walker, who works at the National Optical-Infrared Astronomy Research Laboratory, USA, people should be more aware about this problem. Light pollution is not just about stars, but affects our lives and health, and animals as well.

Walker, along with many other participants across the world, is a part of the Globe at Night project, which began in the 2000s. In this project, participants can compare the stars as seen in the sky with maps of stars at different levels of light pollution. Their observations may be entered into an app. This data can be gathered and further understood by scientists.

A few, such as Christopher Kyba at the GFZ German Research Centre for Geosciences, Germany, had been doubtful of the data collected from the Globe at Night. However, when the individual data points are taken as a whole, they become really useful data to study.

The Globe at Night project and the data become much more valuable when people participate at large. In addition to the Globe at Night project, The New World Atlas of Artificial Night Sky Brightness from 2016 allowed the team to present their findings.