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Light pollution

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Light pollution is a change in the natural patterns of light and dark.

World light pollution
World light pollution

It happens when people use artificial light in a poor or excessive way. This usually occurs at night when the world should be dark. This type of pollution affects the environment and our view of the stars. It can also harm the health of humans, plants, and animals.

Melbourne (AU), Melbourne City Centre -- 2019 -- 1530-4
Melbourne (AU), Melbourne City Centre -- 2019 -- 1530-4

Even though it can happen during the day, the effects are much stronger at night. This is because of the contrast with the dark sky.

There are several ways light pollution works. One way is called light trespass, which is when unwanted light enters a place. For example, a strong light might shine through a bedroom window. This can make it very hard for people to sleep. Another way is skyglow, which is a bright haze above cities.

Skybeamer-uniqema-640
Skybeamer-uniqema-640

This haze is made when artificial light reflects and bounces around in the sky. You might also see glare, which is a bright light that can be hard to look at. Glare can make it difficult for drivers to see the road clearly.

Light pollution also includes over-illumination and light clutter. Over-illumination is using much more light than is actually needed. This can waste a huge amount of electricity. In the United States, homes used 81 billion kilowatt hours of electricity for lighting in 2020.

HPS-lamps
HPS-lamps

Light clutter happens when there are too many lights grouped together. This often occurs with bright advertisements or streetlights. Clutter can be distracting or even cause accidents on the road.

Las Vegas Strip
Las Vegas Strip

These different types of light can often happen at the same time.

People began to notice the harm of light pollution in the late 1800s. However, real efforts to fix it did not start until the 1950s. In the 1980s, a global movement for dark skies began. This led to the founding of the International Dark-Sky Association (IDA).

San Tan Mountain Lights
San Tan Mountain Lights

This group and others now work in many countries. They try to teach people about the importance of protecting the night sky. They also push for new laws to limit unnecessary light.

Today, light pollution is a very large issue for our planet. It is estimated that 83% of the world's people live under light-polluted skies. In North America, 80% of people cannot see the Milky Way galaxy.

Light pollution It's not pretty
Light pollution It's not pretty

Globally, light pollution increased by at least 49% between 1992 and 2017. We can help solve this by using better light bulbs or fixtures. Changing how we use light can help protect both our health and the stars.

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🖼️ Images & Media (17)
File:Melbourne (AU), Melbourne City Centre -- 2019 -- 1530-4.jpg
Melbourne (AU), Melbourne City Centre --...
File:Skybeamer-uniqema-640.jpg
Skybeamer-uniqema-640.jpg
File:Phoenix Lights from afar.jpg
Phoenix Lights from afar.jpg
File:HPS-lamps.jpg
HPS-lamps.jpg
File:Las Vegas Strip.png
Las Vegas Strip.png
File:San Tan Mountain Lights.jpg
San Tan Mountain Lights.jpg
File:Night sky at ESO's Paranal Observatory around twilight, Eso2004a.jpg
Night sky at ESO's Paranal Observatory...
File:World light pollution.jpg
World light pollution.jpg
YOUTUBE HQ-12573 blackmarble 2017 youtube hq.webm
File:Lichtverschmutzung in Kastelruth.JPG
Lichtverschmutzung in Kastelruth.JPG
File:Scorpion in arizona.jpg
Scorpion in arizona.jpg
File:Birds flying trace.jpg
Birds flying trace.jpg

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