Despite a global move to more efficient lighting and various efforts to lessen the impact of lighting on humans and the environment, scientists say both the brightness and the area of Earth lit at night continue to increase by 2.2% each year on average, per a study published in Science Advances this week. That's likely because people are using more lighting now that it is cheaper and more efficient.
Why this matters: Light pollution has been shown to negatively impact human health, environment and ecosystems, and astronomical research. While not surprised, the researchers say they are "very disappointed" with the results. They'd hoped as efficient LED-lighting technology became more available the amount of light emitted from artificial sources would decrease.