Light Pollution Science and Technology Institute

Istituto di Scienza e Tecnologia dell'Inquinamento Luminoso

Light Pollution Science and Technology Institute

The night sky in the World Home Page
How we surveil the situation of the night sky with satellites
The DMSP satellite and its Operational Linescan System
The World Atlas of sea level artificial night sky brightness
Maps of the artificial night sky brightness
Maps of the total night sky brightness
Maps of the naked eye stellar visibility
Maps of the number of visible stars
Maps of the growth of light pollution
Maps of the night sky in selected sites
Our scientific papers
Our group of study
Light Pollution in Italy Web Site
Dep. of Astronomy University of Padova

National Geophysical Data Center - DMSP Nighttime Lights of the World

International Dark-Sky Association - DMSP nighttime  images

NASA - DMSP pages

Earth View

The night sky live

 

Copyright 2000, P. Cinzano, Thiene, Italy

 All rights reserved

 

The night sky in the World

Satellite monitoring of the artificial night sky brightness and the stellar visibility

 

The Night Sky in the Next Century

We are studying the effects of the increase of light pollution which is exponential almost everywhere with average yearly growth rates as large as 5%-10% measured both in US and Europe. Some preliminary projections have been tentatively made based on usual growth rates.

Growth of light pollution in Italy 1971, 1998, 2025.

The figure shows the growth of light pollution in Italy. At left the map of artificial sky brightness in 1971 (Bertiau, Treanor, De Graeve 1973); at centre our map calibrated to 1998; at right a possible scenario of the artificial sky brightness in 2025. We compared Bertiau’s map with a map obtained with satellite data using the same propagation law used by them (Treanor law), we determined the average growth from 1971 to 1998 and then we rescaled our map of 1998 to 2025 assuming the same growth.

This figure is copyright but may be reproduced by the press in articles citing our research with the following credit/copyright statement:

Credit: P. Cinzano, F. Falchi, C. D. Elvidge. Copyright 2001 ISTIL, Thiene. Reproduced from ISTIL Report 2001.

Levels correspond to a fraction of a reference natural sky brightness (251 ucd/m^2):

map 1971 (Bertiau et al.)

Our  map 1998, 2025

<5%

6-15%

black

grey

<11%

black

16-35%

blue

11-33%

blue

36-110%

green

33-100%

green

>1.1

yellow

1-3

yellow

 

 

3-9

orange

 

 

9-27

red

 

 

27-81

violet

 

 

>81

hot white

Yellow indicates an artificial sky brightness equal to the natural (so the total is double). Orange corresponds approximately to areas where the Milky Way is very difficult to see. At sea level, where the majority of the population lives, the Milky Way could be mostly invisible from Italy in 2025. Red corresponds to areas where less than a hundred of stars is visible from the zenith to 30 degrees elevation.

 

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