1.
Atmospheric optics
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Atmospheric optics deals with how the unique optical properties of the Earths atmosphere cause a wide range of spectacular optical phenomena. The blue color of the sky is a result of Rayleigh scattering which redirects higher frequency sunlight back into the field of view of the observer. Because blue light is scattered more easily than red light, the sun takes on a reddish hue when it is observed through a thick atmosphere, additional particulate matter in the sky can scatter different colors at different angles creating colorful glowing skies at dusk and dawn. Scattering off of ice crystals and other particles in the atmosphere are responsible for halos, afterglows, coronas, rays of sunlight, the variation in these kinds of phenomena is due to different particle sizes and geometries. Mirages are optical phenomena in which light rays are bent due to variations in the refraction index of air. Other optical phenomena associated with include the Novaya Zemlya effect where the sun appears to rise earlier or set later than predicted with a distorted shape. Rainbows are the result of a combination of reflection and dispersive refraction of light in raindrops. Because rainbows are seen on the side of the sky as the sun. He said that judging the distance of an object depends on there being a sequence of intervening bodies between the object and the observer. With the Moon, however, there are no intervening objects, therefore, since the size of an object depends on its observed distance, which is in this case inaccurate, the Moon appears larger on the horizon. For over 100 years, research on the Moon illusion has been conducted by scientists who invariably have been psychologists specializing in human perception. After reviewing the different explanations in their 2002 book The Mystery of the Moon Illusion, Ross. Light from the sky is a result of the scattering of sunlight, on a sunny day Rayleigh scattering gives the sky a blue gradient — dark in the zenith, light near the horizon. Light that comes in from overhead encounters 1/38th of the air mass that light coming along a horizon path encounters, so, fewer particles scatter the zenith sunbeam, and therefore the light remains a darker blue. The blueness is at the horizon because the light coming from great distances is also preferentially scattered. This results in a red shift of the far lightsources that is compensated by the hue of the scattered light in the line of sight. In other words, the red light scatters also, if it does so at a point a distance from the observer it has a much higher chance of reaching the observer than blue light. At distances nearing infinity the light is therefore white
2.
Sunlight
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Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is filtered through Earths atmosphere, and is obvious as daylight when the Sun is above the horizon, when the direct solar radiation is not blocked by clouds, it is experienced as sunshine, a combination of bright light and radiant heat. When it is blocked by clouds or reflects off other objects, the World Meteorological Organization uses the term sunshine duration to mean the cumulative time during which an area receives direct irradiance from the Sun of at least 120 watts per square meter. Other sources indicate an Average over the earth of 164 Watts per square meter over a 24 hour day. The ultraviolet radiation in sunlight has both positive and negative effects, as it is both a principal source of vitamin D3 and a mutagen. Sunlight takes about 8.3 minutes to reach Earth from the surface of the Sun. A photon starting at the center of the Sun and changing every time it encounters a charged particle would take between 10,000 and 170,000 years to get to the surface. Researchers may record sunlight using a sunshine recorder, pyranometer, or pyrheliometer, to calculate the amount of sunlight reaching the ground, both Earths elliptical orbit and the attenuation by Earths atmosphere have to be taken into account. In this formula dn–3 is used, because in modern times Earths perihelion, the closest approach to the Sun and, therefore, the value of 0.033412 is determined knowing that the ratio between the perihelion squared and the aphelion squared should be approximately 0.935338. The solar illuminance constant, is equal to 128×103 lx, the atmospheric extinction brings the number of lux down to around 100000. The total amount of energy received at ground level from the Sun at the zenith depends on the distance to the Sun and it is about 3. 3% higher than average in January and 3. 3% lower in July. In terms of energy, sunlight at Earths surface is around 52 to 55 percent infrared,42 to 43 percent visible, and 3 to 5 percent ultraviolet. At the top of the atmosphere, sunlight is about 30% more intense, having about 8% ultraviolet, direct sunlight has a luminous efficacy of about 93 lumens per watt of radiant flux. This is higher than the efficacy of most artificial lighting, which means using sunlight for illumination heats up a less than using most forms of artificial lighting. Multiplying the figure of 1050 watts per square metre by 93 lumens per watt indicates that bright sunlight provides an illuminance of approximately 98000 lux on a surface at sea level. The illumination of a surface will be considerably less than this if the Sun is not very high in the sky. Averaged over a day, the highest amount of sunlight on a horizontal surface occurs in January at the South Pole, dividing the irradiance of 1050 W/m2 by the size of the suns disk in steradians gives an average radiance of 15.4 MW per square metre per steradian. Multiplying this by π gives a limit to the irradiance which can be focused on a surface using mirrors,48.5 MW/m2
3.
Stratocumulus cloud
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Weak convective currents create shallow cloud layers because of drier, stable air above preventing continued vertical development. Most often, stratocumulus produce no precipitation, and when they do, however, these clouds are often seen at either the front or tail end of worse weather, so they may indicate storms to come, in the form of thunderheads or gusty winds. Stratocumulus clouds are same in appearance to altocumulus and are mistaken for such. This often does not apply when stratocumulus is of a broken, fractus form, stratocumulus is also often, though not always, darker in colour than altocumulus. Stratocumulus clouds are the type of cloud that can produce crepuscular rays. Thin stratocumulus clouds are often the cause of corona effects around the Moon at night. All stratocumulus subtypes are coded CL5 except when formed from free convective mother clouds or when formed separately from co-existing, stratocumulus Stratiformis are extensive flat but slightly lumpy sheets that show only minimal convective activity. Stratocumulus Lenticularis are separate flat elongated seed-shaped clouds and they are typical for polar countries or warmer climate during winter seasons. They also can be formed by winds passing hills or mountains, such as Foehn winds, stratocumulus Castellanus have stronger convective activity due to the presence of increasingly unstable air. They are distinct from other stratocumulus by puffy tower-like formations atop the cloud layer, stratocumulus castellanus may develop into cumulus congestus under auspicious conditions. Any showers from stratocumulus castellanus are not usually as heavy as those from cumulus congestus, stratocumulus Opacus is a dark layer of clouds covering entire sky without any break. However, the sheet is not completely uniform, so that separate cloud bases still can be seen. This is the main precipitating type, however any rain is usually light, if the cloud layer becomes grayer to the point when individual clouds can’t be distinguished, stratocumulus turn into stratus clouds. Stratocumulus Perlucidus is a layer of clouds with small spaces, appearing in irregular pattern. Stratocumulus Translucidus consist of groups of stratocumulus clouds, with a clear sky visible between them. Stratocumulus Undulatus clouds appear as nearly parallel waves, rolls or separate elongated clouds, stratocumulus Duplicatus clouds appear as stratocumulus clouds with two or more layers or sheets. Stratocumulus duplicatus is common on species lenticularis or lenticular cloud, stratocumulus Lacunosus clouds are very uncommon. They only occur there are localized downdrafts striking through the stratocumuliform cloud
4.
Twilight
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Twilight is the illumination of the Earths lower atmosphere when the Sun itself is not directly visible because it is below the horizon. Twilight is produced by scattering in the upper atmosphere, illuminating the lower atmosphere so that the surface of the Earth is neither completely lit nor completely dark. The word twilight is also used to denote the periods of time when this illumination occurs, the further the Sun is below the horizon, the dimmer the twilight. When the Sun reaches 18 degrees below the horizon, the brightness is nearly zero. When the Sun again reaches 18 degrees below the horizon, nighttime becomes morning twilight, Twilight should not be confused with auroras, which can have a similar appearance in the night sky at high latitudes. By analogy with evening twilight, the word twilight is also used metaphorically, to imply that something is losing strength. For example, very old people may be said to be in the twilight of their lives, the collateral adjective for twilight is crepuscular which is sometimes applied to insects, fish, and mammals that are most active during that time. Twilight is defined according to the elevation angle θs, which is the position of the geometric center of the sun relative to the horizon. There are three established and widely accepted subcategories of twilight, civil twilight, nautical twilight, and astronomical twilight. Morning civil twilight begins when the center of the sun is 6° below the horizon. Evening civil twilight begins at sunset or when the center of the sun is 0°50′ below the horizon. In the United States military, the initialisms BMCT and EECT are used to refer to these periods, morning nautical twilight begins and evening nautical twilight ends when the geometric center of the sun reaches 12° below the horizon. Morning astronomical twilight begins and Evening astronomical twilight ends when the center of the Sun reaches 18° below the horizon. There are three established and widely accepted subcategories of twilight, civil twilight, nautical twilight, and astronomical twilight, under clear weather conditions, civil twilight approximates the limit at which solar illumination suffices for the human eye to clearly distinguish terrestrial objects. Enough sunlight renders artificial sources unnecessary for most outdoor activities, at civil dawn, the beginning of morning civil twilight, and at civil dusk, the end of evening civil twilight, sunlight clearly defines the horizon while the brightest stars and planets can appear. As observed from the Earth, sky-gazers know Venus, the brightest planet, law-makers have enshrined the concept of civil twilight. Such statutes typically use a period after sunset or before sunrise. The period may affect when pilots require a rating to fly aircraft
5.
Florida
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Florida /ˈflɒrᵻdə/ is a state located in the southeastern region of the United States. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia, to the east by the Atlantic Ocean, Florida is the 22nd-most extensive, the 3rd-most populous, and the 8th-most densely populated of the U. S. states. Jacksonville is the most populous municipality in the state and is the largest city by area in the contiguous United States, the Miami metropolitan area is Floridas most populous urban area. The city of Tallahassee is the state capital, much of the state is at or near sea level and is characterized by sedimentary soil. The climate varies from subtropical in the north to tropical in the south, the American alligator, American crocodile, Florida panther, and manatee can be found in the Everglades National Park. It was a location of the Seminole Wars against the Native Americans. Today, Florida is distinctive for its large Cuban expatriate community and high population growth, the states economy relies mainly on tourism, agriculture, and transportation, which developed in the late 19th century. Florida is also renowned for amusement parks, orange crops, the Kennedy Space Center, Florida has attracted many writers such as Marjorie Kinnan Rawlings, Ernest Hemingway and Tennessee Williams, and continues to attract celebrities and athletes. It is internationally known for golf, tennis, auto racing, by the 16th century, the earliest time for which there is a historical record, major Native American groups included the Apalachee, the Timucua, the Ais, the Tocobaga, the Calusa and the Tequesta. Florida was the first part of the continental United States to be visited and settled by Europeans, the earliest known European explorers came with the Spanish conquistador Juan Ponce de León. Ponce de León spotted and landed on the peninsula on April 2,1513 and he named the region La Florida. The story that he was searching for the Fountain of Youth is a myth, in May 1539, Conquistador Hernando de Soto skirted the coast of Florida, searching for a deep harbor to land. He described seeing a wall of red mangroves spread mile after mile, some reaching as high as 70 feet. Very soon, many smokes appeared along the whole coast, billowing against the sky, the Spanish introduced Christianity, cattle, horses, sheep, the Spanish language, and more to Florida. Both the Spanish and French established settlements in Florida, with varying degrees of success, in 1559, Don Tristán de Luna y Arellano established a settlement at present-day Pensacola, making it the first attempted settlement in Florida, but it was abandoned by 1561. Spain maintained tenuous control over the region by converting the tribes to Christianity. The area of Spanish Florida diminished with the establishment of English settlements to the north, the English attacked St. Augustine, burning the city and its cathedral to the ground several times. Florida attracted numerous Africans and African-Americans from adjacent British colonies who sought freedom from slavery, in 1738, Governor Manuel de Montiano established Fort Gracia Real de Santa Teresa de Mose near St
6.
Reno, Nevada
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Reno is a city in the U. S. state of Nevada. It is in Northern Nevada, approximately 22 miles from Lake Tahoe, known as The Biggest Little City in the World, Reno is famous for its casinos and as the birthplace of Caesars Entertainment Corporation. It is the county seat of Washoe County, in the part of the state. The city sits in a desert at the foot of the Sierra Nevada. Archaeological finds place the border for the prehistoric Martis people in the Reno area. As early as the mid 1850s a few settled in the Truckee Meadows. Gold was discovered in the vicinity of Virginia City in 1850, and a modest mining community developed, to provide the necessary connection between Virginia City and the California Trail, Charles W. Fuller built a log toll bridge across the Truckee River in 1859. A small community that would service travelers soon grew up near the bridge, after two years, Fuller sold the bridge to Myron C. Lake, who continued to develop the community with the addition of a grist mill, kiln, in 1864, Washoe County was consolidated with Roop County, and Lakes Crossing became the largest town in the county. Lake had earned himself the founder of Reno. Lake deeded land to the CPRR in exchange for its promise to build a depot at Lakes Crossing, once the railroad station was established, the town of Reno officially came into being on May 9,1868. CPRR construction superintendent Charles Crocker named the community after Major General Jesse Lee Reno, in 1871, Reno became the county seat of the newly expanded Washoe County, replacing the previous county seat, located in Washoe City. However, political power in Nevada remained with the communities, first Virginia City and later Tonopah. The extension of the Virginia and Truckee Railroad to Reno in 1872 provided a boost to the new citys economy. Despite this, Nevada is still the third-largest gold producer in the world, after South Africa and Australia, the Reno Arch was erected on Virginia Street in 1926 to promote the upcoming Transcontinental Highways Exposition of 1927. The arch included the words Nevadas Transcontinental Highways Exposition and the dates of the exposition. After the exposition, the Reno City Council decided to keep the arch as a permanent downtown gateway, no acceptable slogan was received until a $100 prize was offered, and G. A. Burns of Sacramento was declared the winner on March 14,1929, with Reno, The Biggest Little City in the World
7.
Nevada
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Nevada is a state in the Western, Mountain West, and Southwestern regions of the United States of America. Nevada is the 7th most extensive, the 34th most populous, nearly three-quarters of Nevadas people live in Clark County, which contains the Las Vegas–Paradise metropolitan area where three of the states four largest incorporated cities are located. Nevada is officially known as the Silver State because of the importance of silver to its history and economy. It is also known as the Battle Born State, because it achieved statehood during the Civil War, as the Sage-brush State, for the plant of the same name. Nevada borders Oregon to the northwest, Idaho to the northeast, California to the west, Arizona to the southeast, Nevada is largely desert and semi-arid, much of it located within the Great Basin. Areas south of the Great Basin are located within the Mojave Desert, while Lake Tahoe, about 86% of the states land is managed by various jurisdictions of the U. S. federal government, both civilian and military. Before European contact, Native Americans of the Paiute, Shoshone, the first Europeans to explore the region were Spanish. They called the region Nevada because of the snow covered the mountains in winter. The area formed part of the Viceroyalty of New Spain, the United States annexed the area in 1848 after its victory in the Mexican–American War, and it was incorporated as part of Utah Territory in 1850. The discovery of silver at the Comstock Lode in 1859 led to a boom that became an impetus to the creation of Nevada Territory out of western Utah Territory in 1861. Nevada became the 36th state on October 31,1864, as the second of two added to the Union during the Civil War. Nevada has a reputation for its libertarian laws, in 1940, with a population of just over 110,000 people, Nevada was by far the least-populated state, with less than half the population of the next least-populated state. However, legalized gambling and lenient marriage and divorce laws transformed Nevada into a major tourist destination in the 20th century, Nevada is the only U. S. state where prostitution is legal, though it is illegal in Clark County, Washoe County and Carson City. The tourism industry remains Nevadas largest employer, with mining continuing as a sector of the economy. The name Nevada comes from the Spanish nevada, meaning snow-covered, most Nevadans pronounce the second syllable of their state name using the vowel of trap. Many from outside the Western United States pronounce it with the vowel of father, although the latter pronunciation is closer to the Spanish pronunciation, it is not the pronunciation preferred by most Nevadans. State Assemblyman Harry Mortenson proposed a bill to recognize the alternate pronunciation of Nevada, though the bill was not supported by most legislators, the Nevadan pronunciation is the de facto official one, since it is the one used by the state legislature. Nevada is almost entirely within the Basin and Range Province, and is broken up by many mountain ranges
8.
Jacob's Ladder
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It has since been used as a symbolic reference in various other contexts. The description of Jacobs ladder appears in Genesis 28, 10-19, Jacob left Beersheba and he came to the place and stayed there that night, because the sun had set. Taking one of the stones of the place, he put it under his head and lay down in that place to sleep. And he dreamed, and behold, there was a set up on the earth, and the top of it reached to heaven, and behold. Behold, I am with you and will keep you wherever you go, then Jacob awoke from his sleep and said, Surely the Lord is in this place, and I did not know it. And he was afraid, and said, This is none other than the house of God, afterwards, Jacob names the place, Bethel. The classic Torah commentaries offer several interpretations of Jacobs ladder, according to the Midrash, the ladder signified the exiles which the Jewish people would suffer before the coming of the Messiah. First the angel representing the 70-year exile of Babylonia climbed up 70 rungs, then the angel representing the exile of Persia went up a number of steps, and fell, as did the angel representing the exile of Greece. Only the fourth angel, which represented the final exile of Rome/Edom, Jacob feared that his children would never be free of Esaus domination, but God assured him that at the End of Days, Edom too would come falling down. Another interpretation of the keys into the fact that the angels first ascended. The Midrash explains that Jacob, as a man, was always accompanied by angels. When he reached the border of the land of Canaan, the angels who were assigned to the Holy Land went back up to Heaven, when Jacob returned to Canaan he was greeted by the angels who were assigned to the Holy Land. Yet another interpretation is this, The place at which Jacob stopped for the night was in reality Mount Moriah, the ladder therefore signifies the bridge between Heaven and earth, as prayers and sacrifices offered in the Holy Temple soldered a connection between God and the Jewish people. Moreover, the ladder alludes to the giving of the Torah as another connection between heaven and earth. In this interpretation, it is significant that the Hebrew word for ladder, sulam. The Hellenistic Jewish philosopher Philo, born in Alexandria, presents his interpretation of the ladder in the first book of his De somniis. There he gives four interpretations, which are not mutually exclusive, The angels represent souls descending to, in the second interpretation the ladder is the human soul and the angels are Gods logoi, pulling the soul up in distress and descending in compassion. In the third view the dream depicts the ups and downs of the life of the practiser, finally the angels represent the continually changing affairs of men
9.
Ancient Greece
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Ancient Greece was a civilization belonging to a period of Greek history from the Greek Dark Ages of the 12th-9th centuries BC to the end of antiquity. Immediately following this period was the beginning of the Early Middle Ages and this was followed by the period of Classical Greece, an era that began with the Greco-Persian Wars, lasting from the 5th to 4th centuries BC. Due to the conquests by Alexander the Great of Macedonia, Hellenistic civilization flourished from Central Asia to the end of the Mediterranean Sea. Classical Greek culture, especially philosophy, had a influence on ancient Rome. For this reason Classical Greece is generally considered to be the culture which provided the foundation of modern Western culture and is considered the cradle of Western civilization. Classical Antiquity in the Mediterranean region is considered to have begun in the 8th century BC. Classical Antiquity in Greece is preceded by the Greek Dark Ages and this period is succeeded, around the 8th century BC, by the Orientalizing Period during which a strong influence of Syro-Hittite, Jewish, Assyrian, Phoenician and Egyptian cultures becomes apparent. The end of the Dark Ages is also dated to 776 BC. The Archaic period gives way to the Classical period around 500 BC, Ancient Periods Astronomical year numbering Dates are approximate, consult particular article for details The history of Greece during Classical Antiquity may be subdivided into five major periods. The earliest of these is the Archaic period, in which artists made larger free-standing sculptures in stiff, the Archaic period is often taken to end with the overthrow of the last tyrant of Athens and the start of Athenian Democracy in 508 BC. It was followed by the Classical period, characterized by a style which was considered by observers to be exemplary, i. e. classical, as shown in the Parthenon. This period saw the Greco-Persian Wars and the Rise of Macedon, following the Classical period was the Hellenistic period, during which Greek culture and power expanded into the Near and Middle East. This period begins with the death of Alexander and ends with the Roman conquest, Herodotus is widely known as the father of history, his Histories are eponymous of the entire field. Herodotus was succeeded by authors such as Thucydides, Xenophon, Demosthenes, Plato, most of these authors were either Athenian or pro-Athenian, which is why far more is known about the history and politics of Athens than those of many other cities. Their scope is limited by a focus on political, military and diplomatic history, ignoring economic. In the 8th century BC, Greece began to emerge from the Dark Ages which followed the fall of the Mycenaean civilization, literacy had been lost and Mycenaean script forgotten, but the Greeks adopted the Phoenician alphabet, modifying it to create the Greek alphabet. The Lelantine War is the earliest documented war of the ancient Greek period and it was fought between the important poleis of Chalcis and Eretria over the fertile Lelantine plain of Euboea. Both cities seem to have suffered a decline as result of the long war, a mercantile class arose in the first half of the 7th century BC, shown by the introduction of coinage in about 680 BC
10.
Sunburst
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A sunburst is a design or figure commonly used in architectural ornaments and design patterns. It consists of rays or beams radiating out from a disk in the manner of sunbeams. Sometimes part of a sunburst, a semicircular or semi-elliptical shape, is used, in architecture, the sunburst is often used in window designs, including fanlights and rose windows, as well as in decorative motifs. The sunburst motif is characteristic of Baroque church metalwork, especially monstrances and votive crowns, a sunburst is frequently used in emblems and military decorations. In information visualization, a sunburst diagram or sunburst chart is a pie chart used to represent the proportion of different values found at each level in a hierarchy
11.
Airglow
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Airglow is a faint emission of light by a planetary atmosphere. In the case of Earths atmosphere, this phenomenon causes the night sky never to be completely dark, even after the effects of starlight. The airglow phenomenon was first identified in 1868 by Swedish physicist Anders Ångström, since then, it has been studied in the laboratory, and various chemical reactions have been observed to emit electromagnetic energy as part of the process. Scientists have identified some of those processes that would be present in Earths atmosphere and it is not noticeable during the daytime because of the scattered light from the sun. Even at the best ground-based observatories, airglow limits the sensitivity of telescopes at visible wavelengths, partly for this reason, space-based telescopes such as the Hubble Space Telescope can observe much fainter objects than current ground-based telescopes at visible wavelengths. The airglow at night may be enough to be noticed by an observer and is generally bluish in colour. Very low down, however, atmospheric extinction reduces the apparent brightness of the airglow, one airglow mechanism is when an atom of nitrogen combines with an atom of oxygen to form a molecule of nitric oxide. In the process, a photon is emitted and this photon may have any of several different wavelengths characteristic of nitric oxide molecules. The free atoms are available for process, because molecules of nitrogen and oxygen are dissociated by solar energy in the upper reaches of the atmosphere. Other species that can create air glow in the atmosphere are hydroxyl, atomic oxygen, the sky brightness is typically quoted in units of astronomical magnitudes per square arcsecond of sky. 0×10−12 W cm−2 µm−1.5 × S0 × B h ν. This gives the number of photons from airglow, Na, N a =10 −23 /2, a hypothetical 8 m Hubble telescope would take about 30 minutes. A space telescope isnt restricted by the field, since they are not impacted by airglow. Scientific experiments have been conducted to induce airglow by directing high-power radio emissions at the Earths ionosphere and these radiowaves interact with the ionosphere to induce faint but visible optical light at specific wavelengths under certain conditions. SwissCube-1 is a Swiss satellite operated by Ecole Polytechnique Fédérale de Lausanne, the spacecraft is a single unit CubeSat, which was designed to conduct research into airglow within the Earths atmosphere and to develop technology for future spacecraft. Though SwissCube-1 is rather small and weighs less than 1 kg, the first SwissCube-1 image came down on February 18,2011 and was quite black with some thermal noise on it. The first airglow image came down on March 3,2011 and this image has been converted to the human optical range from its near-infrared measurement. This image provides a measurement of the intensity of the phenomenon in the near-infrared. The range measured is from 500 to 61400 photons, with a resolution of 500 photons, the Venus Express spacecraft contains an infrared sensor which has detected near-IR emissions from the upper atmosphere of Venus
12.
Light beam
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A light beam or beam of light is a directional projection of light energy radiating from a light source. Sunlight forms a light beam when filtered through media such as clouds, foliage, to artificially produce a light beam, a lamp and a parabolic reflector is used in many lighting devices such as spotlights, car headlights, PAR Cans and LED housings. Light from certain types of laser has the smallest possible beam divergence. From the side, a beam of light is visible if part of the light is scattered by objects, tiny particles like dust, water droplets, hail, snow, or smoke. If there are objects in the light path, then it appears as a continuous beam. In any case, this scattering of light from a beam, flashlight, beam directed by hand Headlight, forward beam, the lamp is mounted in a vehicle, or on the forehead of a person, e. g. The difference between the two is that the fog itself is also a visual effect, Laser lighting display- Laser beams are often used for visual effects, often in combination with music. This also used to be done for movie premieres, the waving searchlight beams are still to be seen as an element in the logo of the 20th Century Fox movie studio
