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ALAN Conference Series

ALAN 6 will take place from 16-18.06.2020 in Lleida, Spain.

Night Sky Data to the People!

A new website presents citizen science data

Touring Exhibition

Our touring exhibition with 15 posters can be borrowed for events!

'Loss of the Night' App

The 'Loss of the Night' app measures sky brightness! Take part in a world-wide citizen science project that measures star visibility and light pollution. The app is free!

City Night Time Lapse

This growing collection of time lapse videos of nights in urban centres provides insights how city lights change throughout the course of the night

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Taking astronomy as an example, the dark sides of artificial lighting is very obvious. The light domes above our cities yearly increase by 5 per cent, extinguishing the starry sky by creating an artificial twilight. Light emitted from point sources (street lighting, traffic, luminous advertising and so on) becomes a light carpet in which the starlight drowns, when it is being reflected on streets and house walls as well as by the scattering on floating particles in the air.

A normal European citizen is almost forced to travel, in order to see stars and the Milky Way. Due to this, astronomic observatories were moved from the cities into less "light polluted" areas already in 1900. The Berlin Observatory, for example, was forced to move from the centre to Babelsberg in 1913 because of the poor observation conditions. Without such areas with low light, the revolutionary astronomic discoveries of the last hundred years would not have been possible.

Projects in this field of research:

The AIP and the IGB research both the topic "Detailed characterisation of natural and artificial night sky brightness in a peri-urban and a remote location".