At Mitzpe Ramon, the lights were turned off on the night of the "Geminid shower," so the astronomers saw the light of the zodiac
Dr. Noah Brosh
Humanity continues to move forward, but sometimes progress harms science. One of the damaged sciences is astronomy: the night sky is "lost" in the wild background lighting that originates from cities.
This is not only an Israeli problem - but the property of the whole world. The background lighting raises the detection threshold of pale objects, such as faint stars. This is the reason that in the heart of the big cities, you no longer see the stars; The night sky is lit up so much that their light surpasses the light of the stars.
The reason for the background lighting of the sky is partly natural - and mostly artificial. In the upper layers of the atmosphere, at an altitude of about 100 km, photons of light are emitted from the processes of connecting electrons to ions. The density of the atmosphere at this height is low, but there the processes that cause the emission of light, such as the "Northern Lights", take place.
The natural light of the atmosphere is infinitely weaker than the diffused light of artificial lighting. The light from the headlights comes because the air molecules scatter it. A beam of light sent from a street lamp, for example, may be released into the sky if the lamp does not have a suitable cover to prevent this.
Not only will the local authority, in whose area the "light pollution" occurs, be responsible for wasting taxpayers' money (the price of electricity) - but part of the light will return to the ground, after the air molecules scatter it back.
From this situation of waste and lighting that is not suitable, stargazers suffer in particular. In Israel there are many expectations, big and small. One that serves the public faithfully is operated by the Israeli Astronomical Society in the heart of the city of Givatayim. Its location is convenient for the audience that comes to watch - but it is really deadly for the ability to observe the pale sky bodies.
This situation does not harm the observatory's educational purpose, since most of the objects on which the audience makes the observations are bright: planets, star clusters, etc. However, in order to be able to see pale sky bodies, distant galaxies, quasars at the edge of the universe - objects that are currently at the forefront of scientific research in astronomy - an especially black sky is needed.
These can be found today only in sites very far from inhabited places, where care is taken to prevent light pollution. The place where Tel Aviv University's Viz Observatory operates, in Mitzpe Ramon, is one of these.
The local council Mitzpe Ramon and its head Dror Devash, have recently been working on using lighting that is especially suitable for an environment where an observatory is located. The lighting in the Negev town is yellow, based on low pressure sodium lamps. It interferes less than others with astronomical observations. Also installing special covers for the headlights, to prevent light leaking into the sky, keeps the background lighting low.
And above all: Mitzpe Ramon completely turns off its urban lighting when a special astronomical event occurs. For example: on the night of the meteor shower (December 14-13) when the astronomers studied the "Geminid" shower. The observation had a particularly dark night, as the lights at the Ramon observatory were turned off to aid the research.
Due to this, it was also possible to photograph the "zodiac light" towards morning: a cone of light that appears above the horizon before sunrise, caused by a source of cosmic light pollution. Dust in the solar system, between us and the sun, scatters light that reaches the earth.
