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False Sunrise
A false sunrise is any of several atmospheric optical phenomena in which the Sun appears to have risen, but is actually still some distance below the horizon. A number of different atmospheric conditions can be responsible for this effect, all of which divert the sunlight in such a way as to allow it to reach the observer's eye, thereby giving the impression that the light comes directly from the Sun itself. The spread of light can sometimes resemble that of the true sun. Several atmospheric phenomena that may alternatively be called a "false sunrise" are: * Simple reflection of the sunlight off the bottom of the clouds. * A type of ice crystal halo, such as an upper tangent arc or, more commonly, an upper sun pillar (similar to a subsun, but extending above the sun instead of below it). Like all halos, these phenomena are caused by the reflection and/or refraction of sunlight by ice crystals suspended in the atmosphere, often in the form of cirrus or cirrostratus clouds. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zodiacal Light
The zodiacal light (also called false dawn when seen before sunrise) is a faint glow of diffuse sunlight scattered by interplanetary dust. Brighter around the Sun, it appears in a particularly dark night sky to extend from the Sun's direction in a roughly triangular shape along the zodiac, and appears with less intensity and visibility along the whole ecliptic as the zodiacal band. Zodiacal light spans the entire sky and contributes to the natural light of a clear and moonless night sky. A related phenomenon is ''gegenschein'' (or ''counterglow''), sunlight backscattered from the interplanetary dust, which appears directly opposite to the Sun as a faint but slightly brighter oval glow. Zodiacal light contributes to the natural light of the sky, though since zodiacal light is very faint, it is often outshone and rendered invisible by moonlight or light pollution. The interplanetary dust in the Solar System forms a thick, pancake-shaped cloud called the zodiacal cloud wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Novaya Zemlya Effect
The Novaya Zemlya effect is a polar mirage caused by high refraction of sunlight between atmospheric thermal layers. The effect gives the impression that the sun is rising earlier than it actually should, and depending on the meteorological situation, the effect will present the Sun as a line or a squaresometimes referred to as the rectangular sunmade up of flattened hourglass shapes. The mirage requires rays of sunlight to travel through an inversion layer for hundreds of kilometres, and depends on the inversion layer's temperature gradient. The sunlight must bend to the Earth's curvature at least to allow an elevation rise of 5° for sight of the solar disk. The first person to record the phenomenon was Gerrit de Veer, a member of Willem Barentsz's ill-fated third expedition into the north polar region in 1596–1597. Trapped by the ice, the party was forced to stay for the winter in a makeshift lodge on the archipelago of Novaya Zemlya and endure the polar night. On ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Light Pillar
A light pillar or ice pillar is an atmospheric optics, atmospheric optical phenomenon in which a vertical light beam, beam of light appears to extend above and/or below a light source. The effect is created by the Reflection (physics), reflection of light from tiny ice crystals that are suspended in the atmosphere or that compose high-altitude clouds (e.g. cirrostratus or cirrus clouds). If the light comes sunlight, from the Sun (usually when it is near or even below the horizon), the phenomenon is called a sun pillar or solar pillar. Light pillars can also be caused moonlight, by the Moon or terrestrial sources, such as streetlights and erupting volcanoes. Formation Since they are caused by the interaction of light with ice crystals, light pillars belong to the family of halo (optical phenomenon), halos. The crystals responsible for light pillars usually consist of flat, Hexagonal crystal family, hexagonal plates, which tend to orient themselves more or less horizontally as th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subsun
A subsun (also spelled sub-sun) is an optical phenomenon that appears as a glowing spot visible within clouds or mist when observed from above. The subsun appears directly below the actual Sun, and is caused by sunlight reflecting off numerous tiny ice crystals suspended in the atmosphere. As such, the effect belongs to the family of halos. It is also known as a "sun candle". Formation The subsun phenomena appears when a region of hexagonal ice crystals act as a large mirror, creating a virtual image of the Sun below the horizon. As they fall through the air, the ice forms plate crystals which orient horizontally, i.e., with their hexagonal surfaces parallel to the Earth's surface. When they are disturbed by turbulence, the plates "wobble", causing their surfaces to deviate some degrees from the ideal horizontal orientation, and causing the reflection (i.e., the subsun) to become elongated vertically. Deformations When the subsun is stretched far enough vertically, it can becom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mirage
A mirage is a naturally-occurring optical phenomenon in which light rays bend via refraction to produce a displaced image of distant objects or the sky. The word comes to English via the French ''(se) mirer'', from the Latin ''mirari'', meaning "to look at, to wonder at". Mirages can be categorized as "inferior" (meaning lower), "superior" (meaning higher) and " Fata Morgana", one kind of superior mirage consisting of a series of unusually elaborate, vertically stacked images, which form one rapidly-changing mirage. In contrast to a hallucination, a mirage is a real optical phenomenon that can be captured on camera, since light rays are actually refracted to form the false image at the observer's location. What the image appears to represent, however, is determined by the interpretive faculties of the human mind. For example, inferior images on land are very easily mistaken for the reflections from a small body of water. Inferior mirage In an inferior mirage, the mirage im ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halo (optical Phenomenon)
A halo () is an optical phenomenon produced by light (typically from the Sun or Moon) interacting with ice crystals suspended in Earth's atmosphere, the atmosphere. Halos can have many forms, ranging from colored or white rings to arcs and spots in the sky. Many of these appear near the Sun or Moon, but others occur elsewhere or even in the opposite part of the sky. Among the best known halo types are the circular halo (properly called the 22° halo), light pillars, and sun dogs, but many others occur; some are fairly common while others are extremely rare. The ice crystals responsible for halos are typically suspended in cirrus cloud, cirrus or cirrostratus clouds in the upper troposphere (), but in cold weather they can also float near the ground, in which case they are referred to as diamond dust. The particular shape and orientation of the crystals are responsible for the type of halo observed. Light is reflection (physics), reflected and refraction, refracted by the ice cr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
False Sunset
A false sunset can refer to one of two related atmospheric optical phenomena: (1) the Sun appears to be setting into or to have set below the horizon while it is actually still some height above the horizon; or (2) the Sun has already set below the horizon, but still appears to be on or above the horizon (thus representing the reverse of a false sunrise). Depending on the circumstances, these phenomena can give the impression of an actual sunset. There are several atmospheric conditions which may cause the effect, most commonly a type of halo, caused by the reflection and refraction of sunlight by small ice crystals in the atmosphere, often in the form of cirrostratus clouds. Depending on which variety of "false sunset" is meant, the halo has to appear either above the Sun (which itself is hidden below the horizon) or below it (in which case the real Sun is obstructed from view, e.g. by clouds or other objects), making the upper and lower tangent arcs, upper and lower sun p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zodiacal Light
The zodiacal light (also called false dawn when seen before sunrise) is a faint glow of diffuse sunlight scattered by interplanetary dust. Brighter around the Sun, it appears in a particularly dark night sky to extend from the Sun's direction in a roughly triangular shape along the zodiac, and appears with less intensity and visibility along the whole ecliptic as the zodiacal band. Zodiacal light spans the entire sky and contributes to the natural light of a clear and moonless night sky. A related phenomenon is ''gegenschein'' (or ''counterglow''), sunlight backscattered from the interplanetary dust, which appears directly opposite to the Sun as a faint but slightly brighter oval glow. Zodiacal light contributes to the natural light of the sky, though since zodiacal light is very faint, it is often outshone and rendered invisible by moonlight or light pollution. The interplanetary dust in the Solar System forms a thick, pancake-shaped cloud called the zodiacal cloud wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gerrit De Veer
Gerrit de Veer (–after 1598) was a Dutch officer on Willem Barentsz' second and third voyages of 1595 and 1596 respectively, in search of the Northeast passage. De Veer kept a diary of the voyages and in 1597, was the first person to observe and record the Novaya Zemlya effect, and the first Westerner to observe hypervitaminosis A caused by consumption of the liver of a polar bear. He wrote ''The Three Voyages of William Barents to the Arctic Regions (1594, 1595, and 1596).'' References 16th-century Dutch explorers Dutch diarists Dutch polar explorers Explorers of Svalbard Explorers of the Arctic 16th-century diarists {{Explorer-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polar Night
Polar night is a phenomenon that occurs in the polar regions of Earth, northernmost and southernmost regions of Earth when the Sun remains below the horizon for more than 24 hours. This only occurs inside the polar circles. The opposite phenomenon, polar day or midnight sun, occurs when the Sun remains above the horizon for more than 24 hours. There are multiple ways to define twilight, the gradual transition to and from darkness when the Sun is below the horizon. "Civil" twilight occurs when the Sun is between 0 and 6 degrees below the horizon. Nearby planets like Venus and bright stars like Sirius are visible during this period. "Nautical" twilight continues until the Sun is 12 degrees below the horizon. During nautical twilight, the horizon is visible enough for navigation. "Astronomical" twilight continues until the Sun has sunk 18 degrees below the horizon. Beyond 18 degrees, refracted sunlight is no longer visible. True night is defined as the period when the sun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Willem Barentsz
Willem Barentsz (; – 20 June 1597), anglicized as William Barents or Barentz, was a Dutch Republic, Dutch navigator, cartographer, and Arctic explorer. Barentsz went on three expeditions to the far north in search for a Northern Sea Route, Northeast passage. He reached as far as Novaya Zemlya and the Kara Sea in his first two voyages, but was turned back on both occasions by ice. During a third expedition, the crew discovered Spitsbergen and Bear Island (Norway), Bear Island, but subsequently became stranded on Novaya Zemlya for almost a year. Barentsz died on the return voyage in 1597. The Barents Sea, among many other places, is named after him. Life and career Willem Barentsz was born around 1550 in the village Formerum on the island Terschelling in the Seventeen Provinces, present-day Netherlands. ''Barentsz'' was not his surname but rather his Dutch_name#Patronymics, patronymic name, short for ''Barentszoon'' "Barent's son". A cartographer by trade, Barentsz sailed to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Novaya Zemlya
Novaya Zemlya (, also , ; , ; ), also spelled , is an archipelago in northern Russia. It is situated in the Arctic Ocean, in the extreme northeast of Europe, with Cape Flissingsky, on the northern island, considered the extreme points of Europe, easternmost point of Europe. To Novaya Zemlya's west lies the Barents Sea and to the east is the Kara Sea. Novaya Zemlya consists of two main islands, the northern Severny Island and the southern Yuzhny Island, which are separated by the Matochkin Strait. Subdivisions of Russia#Administrative divisions, Administratively, it is incorporated as Novaya Zemlya District, one of the administrative divisions of Arkhangelsk Oblast, twenty-one in Arkhangelsk Oblast, Russia.Law #65-5-OZ Municipal divisions of Russia, Municipally, it is incorporated as Novaya Zemlya Urban Okrug.Law #258-vneoch.-OZ Novaya Zemlya was a sensitive military area during the Cold War, and parts of it are still used for airfields today. The Soviet Air Forces, Soviet Air F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
