November 27th, 2014 , 01:32 pm

The world's first atlas of artificial sky illumination (full name - "World Atlas of artificial brightness of the night sky at the zenith at sea level") was compiled by Italian and American scientists based on satellite data. By comparing the information received with data on population density, they were able to divide all the inhabitants of the planet into groups depending on the artificial illumination of the sky in their place of residence. It turned out that a fifth of the planet's population, more than half of the residents of the USA and the EU, respectively, as well as just over 40% of the population of Russia are deprived of the opportunity to see the Milky Way, the zodiacal light and most of the constellations with the naked eye in their place of residence. And finally, a tenth of the inhabitants of the Earth and 1/7 of the inhabitants of Europe and Russia are deprived of the opportunity to see the sky, at least somewhat reminiscent of the night sky.

In addition to showing the degree of light pollution in the sky near cities and other populated areas, this map accurately reflects the economic situation and population distribution in different parts of the world. Central and northern Europe, the east coast of the USA, and Japan are clearly visible. Southwestern Europe, eastern China, northern India, regions of the European part of Russia, and eastern Ukraine “glow” a little weaker. The brightest “spot” in Africa is in its western part, in Nigeria, but this is explained not by human activity, but by flares of burning natural gas.

A strange, intense glow near the Falkland Islands, which is populated more by sheep than people, may also be surprising. According to the compilers of the atlas, the reason lies in active gas and oil production in this area (apparently, associated gas is flared). Similar “lighting” can also be observed in the North Sea, South China Sea and the Persian Gulf.

City sky without light pollution.

This is what the city sky would look like if stars were visible in it.

Time lapse processed by astrophotographer Sergio Garcia Rill

Astrophotographer Sergio Garcia Rill decided to create a simulated version called "Night City Sky".
“I have been photographing the starry sky for several years, which required me to travel out of town to see and photograph it due to light pollution,” Riehl writes on his website. “But I wanted to take a combination of shots where the sky could be seen within the city and did my best to try to simulate what it would look like without light pollution.”
His videos include the cities of Houston, Dallas, Austin and San Antonio.

Electric lighting creates haze in the sky—light pollution—that makes it difficult for us to see the stars.

We owe the mesmerizing spectacle of the starry sky to the emergence of ideas about the infinity of the Universe and the plurality of worlds, the dream of flying to the stars... It invariably inspires artists, writers and poets. How many poems are dedicated to the Milky Way alone! “The month is not visible. The Milky Way is shining...The stars are talking to each other.” - wrote Konstantin Balmont in 1895.

Map of light pollution in Russia (color codes in the following figure)

Color codes for illustrations. The first column indicates the ratio of the artificial brightness of the sky to the natural one. Secondly, the artificial brightness of the sky in mcd/sq.m.

World map of light pollution

US Light Pollution Map

Map of light pollution in Europe

G20 countries ranked by population exposed to light pollution (in μd/sq.m.).

G20 countries ranked by largest contaminated area

But here's a surprise: American and Italian physicists have found that a third of humanity, including 60% of Europeans and almost 80% of North Americans, currently cannot see the Milky Way. The reason for this is light pollution created at night by artificial lighting of populated areas and roads.

Light from artificial light sources scattered in the atmosphere increases the brightness of the night sky. Those who have flown airplanes at night have seen huge glowing domes over major cities. However, the sky also glows over unoccupied areas, since light at high altitudes can travel very far from the source.

This atlas shows that about 83% of the world's population, including more than 99% of the population of the United States and Western Europe, live under light pollution in the sky. The sky is considered polluted when artificial brightness at the zenith exceeds 14 millicandelas per square meter (mcd/sq.m). Note that the brightness of a moonless night sky in clear weather is 200 mcd/sq.m.

The most polluted country in the world is Singapore, where the entire population lives under a sky that is so bright that the eye cannot switch to night vision. Large proportions of the population living with this level of light pollution are found in Kuwait (98%), Qatar (97%), United Arab Emirates (93%), Saudi Arabia (83%), South Korea (66%) and Israel (61%) . It is worth noting that this is due to the high compactness of the population in these countries. Almost all residents of San Marino and Malta cannot see the Milky Way.

The countries least affected by light pollution are Chad, the Central African Republic and Madagascar, where more than three-quarters of residents live in pristine skies. Large areas of Canada and Australia also retained their darkest skies.

Of the large European countries, Germany was the least polluted, and Spain was the most polluted. The night sky remains intact only in small areas in Scotland, Sweden and Norway. Light nighttime light pollution occurs in 23% of the area between 75°N and 60°S, 88% of Europe, and nearly half of the United States, despite the vast open spaces of the American West. Russia has vast areas of uncontaminated territory (more than 80%), but more than 90% of its population lives under a light-polluted sky.

Skyglow interferes with ground-based optical astronomical observations. The effects of light pollution on humans are still poorly understood. How does the opportunity to contemplate a full starry sky affect the development of personality? After all, this is a profound change in the fundamental human experience. As one of the authors of the work noted, there are already entire generations of people in the United States who have never seen the Milky Way.

Light pollution has a significant impact on nature. Artificial light can confuse insects, birds, sea turtles, and other wildlife, putting them in mortal danger.

Light pollution management may be worth considering. You can shield light sources, reduce their brightness, or simply turn them off sometimes.

An interactive pollution map and other data can be viewed at

Artificial sky illumination

Moved from Meteoweb.narod.ru

The world's first atlas of artificial sky illumination (full name - "World Atlas of artificial brightness of the night sky at the zenith at sea level") was compiled by Italian and American scientists based on satellite data. By comparing the information received with data on population density, they were able to divide all the inhabitants of the planet into groups depending on the artificial illumination of the sky in their place of residence. It turned out that 2/3 of the world's population, 99% of the population of the United States and the European Union and 87% of the inhabitants of Russia live in areas with noticeable light pollution. Moreover, a fifth of the planet's population, more than 2/3 and half of the residents of the USA and the EU, respectively, as well as just over 40% of the population of our country are deprived of the opportunity to see the Milky Way with the naked eye in their place of residence. And finally, a tenth of the inhabitants of the Earth and 1/7 of the inhabitants of Europe and Russia are deprived of the opportunity to see the sky, at least somewhat reminiscent of the night sky.
The data needed to compile this atlas was collected using a satellite system that collects radiation in a wide range from 440 to 940 nanometers and is particularly sensitive to rays of 500-650 nm. It is in this range that the main “culprits” of sky illumination emit: powerful mercury (545 and 575 nm) and sodium lamps (540-630 nm). So, the entire territory of the Earth is divided into the following zones: black (, dark gray (0.01-0.11), blue (0.11-0.33), green (0.33-1), yellow (1-3), orange (3-9), red (9-27) and white (>27). The values ​​​​indicated in brackets show how many times the artificial brightness of the sky exceeds the average natural one.

"Light" map of the world.

The natural brightness of the sky is the brightness of such an area in which the eye cannot distinguish individual stars. The main reasons why the night sky, even in the deepest corners of the Earth, is not completely black are the following: glow in the upper atmosphere (chemical reactions emitting photons caused by irradiation of atmospheric gas molecules during the previous day), sunlight reflected by interplanetary particles (t .n. zodiacal light), star light scattered by intergalactic dust, the combined light of stars individually invisible to the eye, and other reasons.
See how accurately this map reflects the economic situation and population distribution in different parts of the world. Central and northern Europe, the east coast of the USA, and Japan are clearly visible. The sound is a little weaker in southwestern Europe, eastern China, northern India, regions of the European part of Russia, and eastern Ukraine. The brightest “spot” in Africa is in its western part, in Nigeria, but this is explained not by human activity, but by flares of burning natural gas.
A strange, intense glow near the Falkland Islands, which is populated more by sheep than people, may also be surprising. According to the compilers of the atlas, the reason lies in active gas and oil production in this area (apparently, associated gas is flared). Similar “lighting” can also be observed in the North Sea, South China Sea and the Persian Gulf.

The figure shows part of the territory of Russia. Try to find your city or region on this map.
According to the compilers of the atlas, the population distribution by exposure zones is as follows:
- black and gray - 13%,
- blue - 7%,
- green - 7%,
- yellow - 13%,
- orange - 26%,
- red - 26%,
- white - 8%.

Map of Moscow and the Moscow region. No comments.

This is often the background of the sky in photographs taken with long exposures in places with strong light exposure.
This photograph was taken in the fall of 2000 in the western Moscow region. The intensity of artificial illumination is 3 times higher than the natural brightness of the sky (the border of the orange and yellow zones).