Astronomically , night is understood to mean maximum darkness, i.e. the span between the end of astronomical twilight in the evening and its start in the morning. Because the border area between day and night, called the day-night border or terminator , is widened to a twilight zone on earth as well as on celestial bodies that have a noticeable atmosphere .
For most people, the night is the time of sleep , but for nocturnal animals such as owls , bats , many insects or some snails, the time of activity. Most countries have a number of noise and other protective regulations for night time and for necessary night shifts , mostly also for morning and shift shifts .
Darkness in the night sky
The most important property of the night is darkness and related biological processes such as night rest , silence and the restriction of human vision to the perception of black and white. For color perception occurs only at surface brightness over a few hundredths of Lux and the brightest stars (see also photopic vision ).
Even with a clear, moonless night sky without external lighting, the sky is not completely black. The recombination glow of the molecules in the atmosphere that were ionized by the sun during the day is responsible for the lightening . This occurs especially with oxygen , nitrogen and sodium . Other natural light sources are zodiacal light and the scattering of terrestrial and star light in lower atmospheric layers ( troposphere ). The brightness of the night sky is thus comparable to that of a star with an apparent brightness of 22 mag , which is why much weaker stars cannot be observed from Earth, even with large telescopes. [Receipt?]
An important question for the further development of astronomy was that of Heinrich Wilhelm Olbers : Why is the night sky dark? It leads to the Olbers paradox . The dark night sky can not be explained with Newtonian physics, or only with great difficulty, because in an infinitely large universe one would have to come across a star in every direction at some point, which would result in a day-bright night sky.
The experience of astronomers and night hikes shows that outdoors, even with a dark night sky, you can see enough after a few minutes of adaptation : in the glow of the stars and the band of the Milky Way , every path can be seen, but also larger bumps. Illumination with a flashlight not only disrupts the eyes' adaptation to darkness , but also creates unpleasant shadow effects. [Receipt?]
A number of natural light sources are visible in the night sky, continuously or intermittently. In addition to the zodiacal light already mentioned, these include:
which can develop different light intensities depending on the location, the state of the atmosphere and cloud cover .
The starlight is nowadays severely restricted in places due to increasing air and light pollution . In our latitudes, its light intensity is usually below 0.03 lux, which means that it falls below the limit at which the human eye can still distinguish details and see colors. The moonlight has a strength between 0.2 and 1.0 lux, for comparison: a sunny day reaches 32,000 to 100,000 lux. In the areas around the two poles, and more rarely in the middle latitudes, the aurora borealis provide one on some nights Light intensity that can significantly exceed 1.0 lux.
In the course of human history, artificial light sources have been developed to lift the darkness of the night. First the darkness was lit with fire pits , then with pine chips , torches , tallow and oil lamps , and finally with candles and lanterns .
The kerosene lamp was invented towards the end of the 18th century, the gas stocking and the incandescent lamp at the end of the 19th century , fluorescent lamps followed in the 20th century and, for outdoor use, the bluish mercury vapor lamp or sodium vapor lamps with their characteristic yellowish light. Mercury and sodium vapor lamps can be clearly seen in the picture opposite. There is currently a trend towards energy-saving lamps .
This development changed many areas of human life . They no longer went to sleep at nightfall, but could stay active with the light until late at night.
Outdoor areas are illuminated with lanterns so that traffic can move unhindered even at night, to convey a feeling of security or for decorative reasons. The first cities to introduce artificial street lighting with gas lamps at the beginning of the 19th century were London, Amsterdam and Paris. In the meantime it is already a matter of " light pollution ": people turn night into day through a lot of lighting. The reflections of all light sources on the ground illuminate the sky so much that in larger cities the stars are barely visible. The human hormone level ( melatonin ) and the depth of sleep are also disturbed. Further problems of light pollution are disturbing influences on nocturnal animals, in particular on insects, which are attracted by the light sources and circle them until they are exhausted. This death of insects also has consequences for the food supply for birds and other animals.
The brightened sky is also a hindrance for astronomers because it outshines more and more stars and especially planar celestial objects despite the larger telescopes . Hobby astronomers have to look for remote corners, and modern observatories can only be built far away from civilization .
From the point of view of meteorology, the night is primarily associated with the radiation of the earth's surface and the associated lowering of the ground and air temperature . Phenomena such as dew , fog , frost or frost can therefore occur at night when there is sufficient humidity . In the early morning , i.e. when all these phenomena become visible to humans with increasing brightness, i. a. the 24-hour temperature minimum is set. It usually occurs just before sunrise and can be roughly calculated using the dew point rule.
Night in the hunt
Night in aviation
In Europe, in the area of responsibility of the European aviation authority EASA , the Standardized European Rules of the Air (SERA) defines the night for aviation as follows: “The hours between the end of civil twilight and the beginning of civil dawn . The civil twilight ends in the evening and begins in the morning when the center of the solar disk 6 ° is below the horizon. "With the entry into force of the air traffic regulations LuftVO as amended on 6 November 2015 are in Germany no longer different rules.
Night in psychology
The fear of the night or darkness is called achluophobia or nyctophobia; it is hardly reduced by protective measures such as night watchmen or other surveillance . Even the lighting, which is often exaggerated today (see light pollution ), only helps to a limited extent because it creates dark areas as well as light.
In a figurative sense, one also speaks of night when someone has to go through a phase of spiritual darkness.
Night in the humanities and social sciences as well as in the arts
In addition to astronomy , numerous sciences deal with the night, such as physics and meteorology (among other things because of the nightly cooling ). In psychology , darkness and night have a connection with experience, fear or curiosity. In literary studies and music, the night is an important motif of poetry and songs . The night is one of the most important motifs of romanticism , since only this is able to emphasize the irrational and thus to unlock the secrets of being. She gave this epoch a mystical and magical consecration and raised it to the medium of the newly discovered transcendence.
The topic “ Sociology of the Night” was worked on by Hans-Werner Prahl , among others . In youth culture, politics and the military, the experience of night plays a role. a. a role in campfires , torchlight parades or in orientation and night exercises .
A night poem
At midnight by Eduard Mörike
The night rose calmly to the land,
Leaned dreaming against the mountain wall,
your eye now sees the golden scales
And the springs rush out cheekily,
they sing in the ear of the mother, of the night, of the
day, of the day that was
The ancient old slumber song,
she pays no attention, she is tired of it;
The blue of the sky sounds sweeter,
The yoke swung like a fleeting hours.
But the springs always keep the word,
The waters still sing in their sleep About
the day, About the day that was
Night music and nocturne
The (also: "the") Nocturne or Notturno (literally: "Nachtgewdend", mostly: "Nocturnal") is a musical form that emerged during the Baroque period, which is not fixed in its line-up and sentence structure. A little night music by Wolfgang Amadeus Mozart is a nightly musical serenade. Above all, the Romantic era brought forth a wealth of artistic output in this area.
Phoenician mythology knows Baau as the personification of the night. Išpanzašepa was venerated by the Hittites as the personification of the night. In Greek mythology, Nyx is the goddess and personification of the night, of which even Zeus was afraid. Erebos , the personification of darkness, was considered their sister. The Nyx corresponds to the Roman Nox .
Nótt , the night in Norse mythology, rides the horse Hrimfaxi across the night sky. Mundilfari , the mover of the world axis, is also considered to be the embodiment of the night. As the third consort of Nótt, Delling begets the Dagr (personification of the day).
- by night and fog , night of the long knives
- Night life , night watchman , night practice , shift work
- Cool off at night
- Chronopsychology , sleep disorder
- Chronobiology , circadian rhythm , fatigue
- Indirect vision , night vision
- Nightshade family , Nychthemeron (day night)
- Well-known events
- Blue night , Venetian night , night of Hanover
- Long Night of Museums , Long Night of Churches , Long Night of Culture , radio , etc.
- Little Kuno , children's film GDR 1963
- Elisabeth Bronfen : Deeper than the day thought. A cultural story of the night. Hanser, Munich 2008, ISBN 978-3-446-23723-0 .
- Heinz-Gerhard Friese: The Aesthetics of the Night. A cultural story . Volume 1, Body and Space , Rowohlt, Reinbek near Hamburg 2011, ISBN 978-3-498-02057-6 .
- Heinz-Gerhard Friese: The dubiousness of the night. Essays. Königshausen & Neumann, Würzburg 2015, ISBN 978-3-8260-5602-4 .
- A. Roger Ekirch : In the hour of the night. A story of darkness. Lübbe, Bergisch Gladbach 2006, ISBN 978-3-7857-2246-6 .
- Gudrun Schwibbe, Regina Bendix: At night - ways into other worlds. Accompanying volume to the exhibition of the same name in the Historisches Museum Hannover , Schmerse, Göttingen 2004, ISBN 3-926920-35-1 .
- Walter Seitter : History of the Night . Philo, Berlin 1999, ISBN 3-8257-0111-5 .
- The dictionary of origin (= Der Duden in twelve volumes . Volume 7 ). 2nd Edition. Dudenverlag, Mannheim 1989, p. 478 . See also DWDS ( "Night" ) and Friedrich Kluge : Etymological Dictionary of the German Language . 7th edition. Trübner, Strasbourg 1910 ( p. 325 ).
- confirmed u. a. by Prof. Thomas Posch, University of Vienna Observatory
- Article 2, No. 97 of the Implementing Regulation 923/2012 of the EU Commission PDF (PDF) .
- Manfred Wacker: The meaning of the night in romance. Epilogue to the Reclam edition by ETA Hoffmann , Der Sandmann . The dreary house . Stuttgart 1989, pp. 88-9 '.