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Information about Zodiacal Light



The zodiacal light is a faint, roughly triangular, whitish glow seen in the night sky which appears to extend up from the vicinity of the sun along the ecliptic or zodiac. In mid-northern latitudes, the zodiacal light is best observed in the western sky in the spring after the evening twilight has completely disappeared, or in the eastern sky in the autumn just before the morning twilight appears. It is so faint that it is completely masked by either moonlight or light pollution. The zodiacal light decreases in intensity with distance from the Sun, but on very dark nights it has been observed in a band completely around the ecliptic. In fact, the zodiacal light covers the entire sky, being responsible for 60% of the total skylight on a moonless night. There is also a very faint, but still slightly increased, oval glow directly opposite the Sun which is known as the gegenschein.

This phenomenon was first investigated by the astronomer Giovanni Domenico Cassini in 1683 and first explained by Nicolas Fatio de Duillier in 1684.

Formation

The zodiacal light is produced by sunlight reflecting off dust particles which are present in the solar system and known as cosmic dust. Consequently, its spectrum is the same as the solar spectrum. The material producing the zodiacal light is located in a lens-shaped volume of space centered on the sun and extending well out beyond the orbit of Earth. This material is known as the interplanetary dust cloud. Since most of the material is located near the plane of the solar system, the zodiacal light is seen along the ecliptic. The amount of material needed to produce the observed zodiacal light is amazingly small. If it were in the form of 1 mm particles, each with the same albedo (reflecting power) as Earth's moon, each particle would be 8 km from its neighbors. The gegenschein may be due to the fact that particles directly opposite the sun as seen from Earth would be in full phase.

The Poynting-Robertson effect causes the particles to spiral slowly into the Sun, thus requiring a continuous source of new particles to maintain the zodiacal cloud. Cometary dust and dust generated by collisions among the asteroids are believed to be mostly responsible for the maintenance of the dust cloud producing the zodiacal light and the gegenschein. In recent years, observations by a variety of spacecraft have shown significant structure in the zodiacal light including dust bands associated with debris from particular asteroid families and several cometary trails.

Historical explanations

Previously, it was believed that zodiacal light was just the atmosphere of the sun. According to the 1728 Cyclopaedia:

"The zodiacal light is nothing but the solar atmosphere, a rare and subtile fluid, either luminous by itself, or made so by the rays of the sun surrounding its globe; but in a greater quantity, and more extensively, about its equator, than any other."

See also

References

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See also astronomical objects, the solar system's list of objects, sorted by radius or mass, and the
The Sun

Observation data
Mean distance
from Earth 1.4961011 m
(8.31 min at light speed)
Visual brightness (V) −26.74m [1]
Absolute magnitude 4.
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ecliptic is the apparent path that the Sun traces out in the sky, as it appears to move in the sky in relation to the stars, this apparent path aligns with the planets throughout the course of the year.
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For other uses, see Zodiac (disambiguation).


The term zodiac denotes an annual cycle of twelve stations along the ecliptic, the apparent path of the sun across the heavens through the constellations that divide the ecliptic into twelve equal
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Seasons

Temperate
Spring
Summer
Autumn
Winter
Tropical
Dry
season Cool
Hot
Wet season

Spring
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Twilight is the time before sunrise or after sunset when sunlight scattered in the upper atmosphere illuminates the lower atmosphere and the surface of the Earth is between light and dark.
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Autumn (also known as Fall in North American English) is one of the four temperate seasons. Autumn marks the transition from summer into winter. In the northern hemisphere, the start of autumn is generally considered to be around September and in the southern hemisphere, its
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Moonlight is the light that comes to Earth from the Moon. This light does not originate from the Moon, but is actually reflected sunlight. The intensity of moonlight varies greatly depending on the current lunar phase, but even the full moon typically provides only a faint
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Light pollution is excess or obtrusive light created by humans. Among other effects, it disrupts ecosystems, can cause adverse health effects, obscures the stars for city dwellers, interferes with astronomical observatories, and wastes energy.
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ecliptic is the apparent path that the Sun traces out in the sky, as it appears to move in the sky in relation to the stars, this apparent path aligns with the planets throughout the course of the year.
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Gegenschein (German for counter shine, pronounced gey-guhn-shahyn), is a faint brightening of the night sky in the region of the ecliptic directly opposite the Sun. It was discovered in 1854 by the Danish astronomer Theodor Brorsen.
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Giovanni Domenico Cassini (June 8, 1625–September 14, 1712) was an Italian-French astronomer, engineer, and astrologer. Cassini, also known as Giandomenico Cassini, was born in Perinaldo, near Sanremo, at that time in the Republic of Genoa.
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Nicolas Fatio de Duillier (26 February 1664 - 12 May 1753) was a Swiss mathematician known for his work on the zodiacal light problem and his role in the Newton v. Leibniz calculus controversy.
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Solar System or solar system[a] consists of the Sun and the other celestial objects gravitationally bound to it: the eight planets, their 166 known moons,[1]
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Cosmic dust is a type of dust composed of particles in space which are a few molecules to 0.1 mm in size. Cosmic dust can be further distinguished by its astronomical location; for example: intergalactic dust, interstellar dust, circumplanetary dust, dust clouds around other stars,
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Spectroscopy is the study of the interaction between radiation (electromagnetic radiation, or light, as well as particle radiation) and matter. Spectrometry is the measurement of these interactions and an instrument which performs such measurements is a spectrometer or
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The Sun

Observation data
Mean distance
from Earth 1.4961011 m
(8.31 min at light speed)
Visual brightness (V) −26.74m [1]
Absolute magnitude 4.
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ORBit is a CORBA compliant Object Request Broker (ORB). The current version is called ORBit2 and is compliant with CORBA version 2.4. It is developed under the GPL license and is used as middleware for the GNOME project.
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The interplanetary dust cloud has been studied for many years in order to understand its nature, origin, and relationship to planetary systems (our own, as well as extrasolar systems).
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The albedo of an object is the extent to which it reflects light, defined as the ratio of reflected to incident electromagnetic radiation. It is a unitless measure indicative of a surface's or body's diffuse reflectivity.
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Moon  

The Moon as seen by an observer on Earth
Orbital characteristics
Periapsis: 363,104 km
0.0024 AU
Apoapsis: 405,696 km
0.0027 AU
Semi-major axis: 384,399 km
0.
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Lunar phase refers to the appearance of the illuminated portion of the Moon as seen by an observer, usually on Earth. The lunar phases vary cyclically as the Moon orbits the Earth, according to the changing geometry of the Earth, Moon, and Sun.
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The Poynting-Robertson effect, also known as Poynting-Robertson drag, named after John Henry Poynting and Howard Percy Robertson, is a process by which solar radiation causes a dust grain in the solar system to slowly spiral inward.
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comet is a small body in the solar system that orbits the Sun and (at least occasionally) exhibits a coma (or atmosphere) and/or a tail — both primarily from the effects of solar radiation upon the comet's nucleus, which itself is a minor body composed of rock, dust, and
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Asteroids, also called minor planets or planetoids, are a class of astronomical objects. The term asteroid is generally used to indicate a diverse group of small celestial bodies in the solar system that orbit around the Sun.
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Gegenschein (German for counter shine, pronounced gey-guhn-shahyn), is a faint brightening of the night sky in the region of the ecliptic directly opposite the Sun. It was discovered in 1854 by the Danish astronomer Theodor Brorsen.
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Minor planets, or asteroids or planetoids, are minor celestial bodies of the Solar system orbiting the Sun (mostly Small solar system bodies) that are smaller than major planets, but larger than meteoroids (commonly defined as being 10 meters across or less
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Cyclopaedia: or, An Universal Dictionary of Arts and Sciences (folio, 2 vols.) was an encyclopedia published by Ephraim Chambers in London in 1728, and reprinted in numerous editions in the 18th Century.
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An optical phenomenon is any observable event which results from the interaction of light and matter. See also list of optical topics and optics.

Common optical phenomena are often due to the interaction of light from the sun or moon with the atmosphere, clouds, water, or
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Zodiacal dust forms a pancake shaped cloud in the Solar System collectively known as the zodiacal cloud. It occupies the same plane as the orbit of the planets from which it derives the name zodiac. The dust particles, are between 1 to 300 micrometres in diameter.
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Cyclopaedia: or, An Universal Dictionary of Arts and Sciences (folio, 2 vols.) was an encyclopedia published by Ephraim Chambers in London in 1728, and reprinted in numerous editions in the 18th Century.
..... Click the link for more information.


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