1.
Very Large Telescope
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The Very Large Telescope is a telescope facility operated by the European Southern Observatory on Cerro Paranal in the Atacama Desert of northern Chile. The VLT consists of four telescopes, each with a primary mirror 8.2 m across. The four separate optical telescopes are known as Antu, Kueyen, Melipal and Yepun, the telescopes form an array which is complemented by four movable Auxiliary Telescopes of 1.8 m aperture. The VLT operates at visible and infrared wavelengths.001 arc-second and this is equivalent to roughly 2 meters resolution at the distance of the Moon. In single telescope mode of operation angular resolution is about 0.05 arc-second, the VLT is the most productive ground-based facility for astronomy, with only the Hubble Space Telescope generating more scientific papers among facilities operating at visible wavelengths. The VLT consists of an arrangement of four large telescopes with optical elements that can combine them into an astronomical interferometer, the interferometer also includes a set of four 1.8 meter diameter movable telescopes dedicated to interferometric observations. The first of the UTs started operating in May 1998 and was offered to the community on 1 April 1999. The other telescopes followed suit in 1999 and 2000, thus making the VLT fully operational, four 1. 8-metre Auxiliary Telescopes have been added to the VLTI to make it available when the UTs are being used for other projects. These ATs were installed between 2004 and 2007, today, all four Unit Telescopes and all four Auxiliary Telescopes are operational. The VLTs 8. 2-meter telescopes were designed to operate in three modes, as a set of four independent telescopes. as a single large coherent interferometric instrument. This mode is used, only for observations of relatively bright sources with small angular extent. As a single large incoherent instrument, for extra light-gathering capacity, the instrumentation required to bring the light to a combined incoherent focus was not built. Recently, new proposals have been put forward for making this observing mode available. Multiple telescopes are sometimes independently pointed at the object, either to increase the total light-gathering power. In particular, the VLT has several adaptive optics systems, which correct for the effects of atmospheric turbulence, providing images almost as sharp as if the telescope were in space. In the near-infrared, the adaptive optics images of the VLT are up to three times sharper than those of the Hubble Space Telescope, and the resolution is many times better than Hubble. The VLTs are noted for their level of observing efficiency. The 8.2 m-diameter telescopes are housed in compact, thermally controlled buildings, the principal role of the main VLT telescopes is to operate as four independent telescopes
2.
VLT Survey Telescope
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The VLT Survey Telescope is the latest telescope to be added to ESO’s Paranal Observatory in the Atacama Desert of northern Chile. It is housed in an immediately adjacent to the four Very Large Telescope Unit Telescopes on the summit of Cerro Paranal. The VST is a survey telescope with a field of view twice as broad as the full Moon. It is the largest telescope in the designed to exclusively survey the sky in visible light. The VST program is a cooperation between the Osservatorio Astronomico di Capodimonte, Naples, Italy, and the European Southern Observatory that began in 1997, vSTcen was founded and directed by Prof. Massimo Capaccioli of the VST project, and hosted at the OAC. ESO and VSTceN collaborated in the phase, while ESO was responsible for the civil engineering works. The telescope has now started observations and ESO is solely responsible for managing its operations, the VST is an alt-azimuthal wide-field survey telescope with a primary mirror diameter of 2.65 meters that was constructed from 2007–2011 at the ESO Cerro Paranal Observatory, in Chile. Together with its camera OmegaCAM, the VST is able to obtain a high angular resolution, the telescope has two mirrors, the primary and a smaller secondary mirror, which reflect light from the sky down to the OmegaCAM camera. Both mirrors are made from a ceramic material called Sitall. The VST primary mirror is the larger of the two, with a diameter of 265 cm and a thickness of 14 cm, the secondary mirror is less than half the size of M1 with a diameter of just 93.8 cm and a thickness of 13 cm. VSTs original optical components were manufactured at the Lytkarino Glass Factory, a computer-controlled active optics system controls the shape of M1 and the position of M2. This technology preserves the image quality by keeping the mirrors perfectly positioned at all times. M1 is continuously reshaped by a network of 84 axial motors distributed under the mirror surface and 24 radial dislocated laterally. The secondary mirror is controlled by a deformable platform able to tilt the mirror during exposure. The active optics system also includes a Shack-Hartmann wavefront sensor, mounted under the primary mirror cell together with the guide system. These systems give the VST the capability to be autonomous in terms of guiding, tracking, design features of OmegaCAM include four auxiliary CCD cameras, two for auto-guiding and two for on-line image analysis. Up to 12 filters can be used, ranging from ultraviolet to near-infrared, the entire detector system operates in vacuum at about -140 degrees Celsius behind a large dewar window. This window not only protects the detectors from air and moisture, the primary function of the VST is to support the Very Large Telescope by providing surveys – both extensive, multi-colour imaging surveys and more specific searches for rare astronomical objects
3.
European Southern Observatory
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The European Southern Observatory is a 16-nation intergovernmental research organization for ground-based astronomy. Created in 1962, ESO has provided astronomers with state-of-the-art research facilities, the organisation employs about 730 staff members and receives annual member state contributions of approximately €131 million. Its observatories are located in northern Chile, ESO has built and operated some of the largest and most technologically advanced telescopes. The Atacama Large Millimeter Array observes the universe in the millimetre and submillimetre wavelength ranges and it was completed in March 2013 in an international collaboration by Europe, North America, East Asia and Chile. Currently under construction is the European Extremely Large Telescope and it will use a 39. 3-metre-diameter segmented mirror, and become the worlds largest optical reflecting telescope when operational in 2024. ESOs observing facilities have made discoveries and produced several astronomical catalogues. Its findings include the discovery of the most distant gamma-ray burst, in 2004, the VLT allowed astronomers to obtain the first picture of an extrasolar planet orbiting a brown dwarf 173 light-years away. The idea that European astronomers should establish a large observatory was broached by Walter Baade. It was pursued by Oort, who gathered a group of astronomers in Leiden to consider it on June 21 that year, immediately thereafter, the subject was further discussed at the Groningen conference in the Netherlands. On January 26,1954, an ESO declaration was signed by astronomers from six European countries expressing the wish that a joint European observatory be established in the southern hemisphere. At the time, all reflector telescopes with an aperture of 2 metres or more were located in the northern hemisphere. The decision to build the observatory in the southern hemisphere resulted from the necessity of observing the southern sky, although it was initially planned to set up telescopes in South Africa, tests from 1955 to 1963 demonstrated that a site in the Andes was preferable. On November 15,1963 Chile was chosen as the site for ESOs observatory, the decision was preceded by the ESO Convention, signed 5 October 1962 by Belgium, Germany, France, the Netherlands and Sweden. Otto Heckmann was nominated as the organisations first director general on 1 November 1962, a preliminary proposal for a convention of astronomy organisations in these five countries was drafted in 1954. Although some amendments were made in the document, the convention proceeded slowly until 1960 when it was discussed during that years committee meeting. The new draft was examined in detail, and a member of CERN highlighted the need for a convention between governments. The convention and government involvement became pressing due to rising costs of site-testing expeditions. The final 1962 version was adopted from the CERN convention
4.
Chile
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Chile, officially the Republic of Chile, is a South American country occupying a long, narrow strip of land between the Andes to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, Chilean territory includes the Pacific islands of Juan Fernández, Salas y Gómez, Desventuradas, and Easter Island in Oceania. Chile also claims about 1,250,000 square kilometres of Antarctica, the arid Atacama Desert in northern Chile contains great mineral wealth, principally copper. Southern Chile is rich in forests and grazing lands, and features a string of volcanoes and lakes, the southern coast is a labyrinth of fjords, inlets, canals, twisting peninsulas, and islands. Spain conquered and colonized Chile in the century, replacing Inca rule in northern and central Chile. After declaring its independence from Spain in 1818, Chile emerged in the 1830s as a relatively stable authoritarian republic, in the 1960s and 1970s the country experienced severe left-right political polarization and turmoil. The regime, headed by Augusto Pinochet, ended in 1990 after it lost a referendum in 1988 and was succeeded by a coalition which ruled through four presidencies until 2010. Chile is today one of South Americas most stable and prosperous nations and it leads Latin American nations in rankings of human development, competitiveness, income per capita, globalization, state of peace, economic freedom, and low perception of corruption. It also ranks high regionally in sustainability of the state, Chile is a founding member of the United Nations, the Union of South American Nations and the Community of Latin American and Caribbean States. There are various theories about the origin of the word Chile, another theory points to the similarity of the valley of the Aconcagua with that of the Casma Valley in Peru, where there was a town and valley named Chili. Another origin attributed to chilli is the onomatopoeic cheele-cheele—the Mapuche imitation of the warble of a locally known as trile. The Spanish conquistadors heard about this name from the Incas, ultimately, Almagro is credited with the universalization of the name Chile, after naming the Mapocho valley as such. The older spelling Chili was in use in English until at least 1900 before switching over to Chile, stone tool evidence indicates humans sporadically frequented the Monte Verde valley area as long as 18,500 years ago. About 10,000 years ago, migrating Native Americans settled in fertile valleys, settlement sites from very early human habitation include Monte Verde, Cueva del Milodon and the Pali Aike Craters lava tube. They fought against the Sapa Inca Tupac Yupanqui and his army, the result of the bloody three-day confrontation known as the Battle of the Maule was that the Inca conquest of the territories of Chile ended at the Maule river. The next Europeans to reach Chile were Diego de Almagro and his band of Spanish conquistadors, the Spanish encountered various cultures that supported themselves principally through slash-and-burn agriculture and hunting. The conquest of Chile began in earnest in 1540 and was carried out by Pedro de Valdivia, one of Francisco Pizarros lieutenants, who founded the city of Santiago on 12 February 1541. Although the Spanish did not find the gold and silver they sought, they recognized the agricultural potential of Chiles central valley
5.
Observatory
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An observatory is a location used for observing terrestrial or celestial events. Astronomy, climatology/meteorology, geology, oceanography and volcanology are examples of disciplines for which observatories have been constructed, historically, observatories were as simple as containing an astronomical sextant or Stonehenge. Astronomical observatories are mainly divided into four categories, space based, airborne, ground based, ground-based observatories, located on the surface of Earth, are used to make observations in the radio and visible light portions of the electromagnetic spectrum. Most optical telescopes are housed within a dome or similar structure, Telescope domes have a slit or other opening in the roof that can be opened during observing, and closed when the telescope is not in use. In most cases, the upper portion of the telescope dome can be rotated to allow the instrument to observe different sections of the night sky. Radio telescopes usually do not have domes, for optical telescopes, most ground-based observatories are located far from major centers of population, to avoid the effects of light pollution. The ideal locations for modern observatories are sites that have dark skies, a percentage of clear nights per year, dry air. At high elevations, the Earths atmosphere is thinner, thereby minimizing the effects of atmospheric turbulence, sites that meet the above criteria for modern observatories include the southwestern United States, Hawaii, Canary Islands, the Andes, and high mountains in Mexico such as Sierra Negra. Major optical observatories include Mauna Kea Observatory and Kitt Peak National Observatory in the USA, Roque de los Muchachos Observatory in Spain, and Paranal Observatory in Chile. Specific research study performed in 2009 shows that the best possible location for ground-based observatory on Earth is Ridge A — a place in the part of Eastern Antarctica. This location provides the least atmospheric disturbances and best visibility, beginning in 1930s, radio telescopes have been built for use in the field of radio astronomy to observe the Universe in the radio portion of the electromagnetic spectrum. Since the mid-20th century, a number of observatories have been constructed at very high altitudes, above 4. The largest and most notable of these is the Mauna Kea Observatory, the Chacaltaya Astrophysical Observatory in Bolivia, at 5,230 m, was the worlds highest permanent astronomical observatory from the time of its construction during the 1940s until 2009. It has now surpassed by the new University of Tokyo Atacama Observatory. As a result, the resolution of space telescopes such as the Hubble Space Telescope is often much smaller than a ground-based telescope with a similar aperture. However, all these advantages do come with a price, Space telescopes are much more expensive to build than ground-based telescopes. Due to their location, space telescopes are also difficult to maintain. The Hubble Space Telescope was serviced by the Space Shuttle while many other space telescopes cannot be serviced at all, Airborne observatories have the advantage of height over ground installations, putting them above most of the Earths atmosphere
6.
Antofagasta
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Antofagasta is a port city in northern Chile, about 1,100 kilometres north of Santiago. It is the capital of Antofagasta Province and Antofagasta Region, according to the 2012 census, the city has a population of 345,420. The city of Antofagasta is closely linked to mining activity, being a mining area of the country. The last decade has been a growth in the areas of construction, retail, hotel accommodations, population growth. Antofagasta has the highest GDP per capita of Chile,37,000 USD, currently there are several theories to explain the origin of the name Antofagasta. A clear consensus regarding the origin of the word has not yet been determined. It is probably a word that comes from the southern Cacan anto, faya and gasta. However, it says the name Antofagasta is due to a decision by Manuel Mariano Melgarejo, in Chile, Antofagasta is known as La Perla del Norte, for its historical and economic importance. On 18 September 1866, José Santos Ossa and Francisco Puelma achieved the award of the concession of nitrate lands, the exploring of the Chilean miners found rich deposits of saltpeter in the field of Salar del Carmen, to the east of the present Antofagasta. Agreed to form the Sociedad Exploradora del Desierto de Atacama, after the formation of the company, began to fill with what was called La Chimba. On 19 March 1868, the Melbourne Clark Company was established, after the integration of Chilean, after the earthquake in Iquique and Oprah Jiffy of 13 August 1868, it was necessary to give legal recognition to the Chimba as a mining town. On 22 October 1868, the population was established and the port under the name La Chimba. Later the city was renamed Antofagasta, the first official map of the population and the port of Antofagasta was designed by Jose Santos Prada on 14 September 1869. This document set out the grounds of the Melbourne Clark Company, plus 17 blocks, on 8 May 1872, Antofagasta was appointed by the Bolivian Government as Puerto Mayor, open trade worldwide. On 27 November 1873, the Compañía de Salitres y Ferrocarril de Antofagasta signed a contract with the government of Bolivia and this contract was not ratified by the Congress of Bolivia, which was then analyzed negotiations with Chile. In 1873 Bolivia signed a treaty of defensive alliance with Peru. This would be used as an argument 5 years later in Chile, the secret alliance, forbade Bolivia from signing a border treaty with Chile, without consulting with Peru. However, in 1874 Chile and Bolivia signed a border treaty, one of its points was not to impose new taxes on individuals, industries and Chilean capital for 25 years
7.
Next-Generation Transit Survey
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The Next-Generation Transit Survey is a ground-based robotic search for exoplanets. The facility is located at Paranal Observatory on the outskirts of the Atacama desert in northern Chile, science operations began in early 2015. The astronomical survey is managed by a consortium of seven European universities and other institutions from Chile, Germany, Switzerland. Prototypes of the array were tested in 2009 and 2010 on La Palma, the aim of NGTS is to discover super-Earths and exo-Neptunes transiting relatively bright and nearby stars with an apparent magnitude of up to 13. The survey uses transit photometry, which measures the dimming of a star to detect the presence of a planet when it crosses in front of it. NGTS consists of an array of twelve commercial 0. 2-metre telescopes, each equipped with a red-sensitive CCD camera operating in the visible, the array covers an instantaneous field of view of 96 square degrees or around 0. 23% of the entire sky. NGTS builds heavily on the experience of its predecessor, SuperWASP, using more sensitive detectors, refined software, as a result, the number of discovered nearby exoplanets will be much larger. NGTS is designed to fill the current gap between Earth-sized planets and gas giants, nGTSs wider field of view enables it to detect a larger number of more-massive planets around brighter stars. With a detailed follow-up characterization by larger instruments such as HARPS, ESPRESSO and VLT-SPHERE and this makes it possible to determine the exoplanets density, and hence whether it is gaseous or rocky. Ground-based surveys for extrasolar planets such as WASP and the HATNet Project have discovered many large exoplanets, mainly Saturn-, space-based missions such as CoRoT and the Kepler survey have extended the results to smaller objects, including rocky super-Earth- and Neptune-sized exoplanets. Orbiting space missions have an accuracy of stellar brightness measurement than is possible via ground-based measurements. Unfortunately, most of the smaller candidates orbit stars that are too faint for confirmation by radial-velocity measurements, the masses of these smaller candidate planets are hence either unknown or poorly constrained, such that their bulk composition cannot be estimated. Such targets are more readily characterized in terms of their composition, planetary structure. In follow-up observations by larger telescopes, powerful means will be available to probe the composition of exoplanets discovered by NGTS. Calculation of the spectrum of the planets atmosphere can be obtained by measuring the small spectral changes in the spectrum of the star that arise during the planets transit. NGTS is intended to increase the number of planets that are analyzable using such techniques. The scientific goals of the NGTS require being able to detect transits with a precision of 1 mmag at 13th magnitude, although at ground level this level of accuracy was routinely achievable in narrow-field observations of individual objects, it was unprecedented for a wide-field survey. NGTS employs an array of twelve 20-centimeter f/2.8 telescopes on independent equatorial mounts
8.
Exoplanet
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An exoplanet or extrasolar planet is a planet that orbits a star other than the Sun. The first scientific detection of an exoplanet was in 1988, HARPS has discovered about a hundred exoplanets while the Kepler space telescope has found more than two thousand. Kepler has also detected a few thousand candidate planets, of which about 11% may be false positives, on average, there is at least one planet per star, with a percentage having multiple planets. About 1 in 5 Sun-like stars have an Earth-sized planet in the habitable zone, the least massive planet known is Draugr, which is about twice the mass of the Moon. There are planets that are so near to their star that they take only a few hours to orbit, some are so far out that it is difficult to tell whether they are gravitationally bound to the star. Almost all of the planets detected so far are within the Milky Way, the nearest exoplanet is Proxima Centauri b, located 4.2 light-years from Earth and orbiting Proxima Centauri, the closest star to the Sun. The discovery of exoplanets has intensified interest in the search for extraterrestrial life, there is special interest in planets that orbit in a stars habitable zone, where it is possible for liquid water, a prerequisite for life on Earth, to exist on the surface. The study of planetary habitability also considers a range of other factors in determining the suitability of a planet for hosting life. The rogue planets in the Milky Way possibly number in the billions, the convention for designating exoplanets is an extension of the system used for designating multiple-star systems as adopted by the International Astronomical Union. For exoplanets orbiting a star, the designation is normally formed by taking the name or, more commonly, designation of its parent star. The first planet discovered in a system is given the designation b, if several planets in the same system are discovered at the same time, the closest one to the star gets the next letter, followed by the other planets in order of orbital size. A provisional IAU-sanctioned standard exists to accommodate the designation of circumbinary planets, a limited number of exoplanets have IAU-sanctioned proper names. Various detection claims made in the century were rejected by astronomers. The first scientific detection of an exoplanet began in 1988, However, the first confirmed detection came in 1992, with the discovery of several terrestrial-mass planets orbiting the pulsar PSR B1257+12. The first confirmation of an exoplanet orbiting a star was made in 1995. Some exoplanets have been imaged directly by telescopes, but the vast majority have been detected through indirect methods, such as the transit method, in the eighteenth century the same possibility was mentioned by Isaac Newton in the General Scholium that concludes his Principia. Claims of exoplanet detections have been made since the nineteenth century, some of the earliest involve the binary star 70 Ophiuchi. In 1855 William Stephen Jacob at the East India Companys Madras Observatory reported that orbital anomalies made it highly probable that there was a body in this system
9.
Extremely Large Telescope
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The European Extremely Large Telescope is an astronomical observatory and the worlds largest optical/near-infrared extremely large telescope now under construction. Part of the European Southern Observatory, it is located on top of Cerro Armazones in the Atacama Desert of northern Chile, the observatory aims to gather 13 times more light than the largest optical telescopes existing in 2014, and be able to correct for atmospheric distortions. It has around 256 times the light gathering area of the Hubble Space Telescope and, according to the E-ELTs specifications, the facility is expected to take 11 years to construct. Construction work on the E-ELT site started in June 2014, by December 2014, ESO had secured over 90% of the total funding and authorized construction of the telescope to start, which will cost around one billion Euro for the first construction phase. First light is planned for 2024, on 26 April 2010, the European Southern Observatory Council selected Cerro Armazones, Chile, as the baseline site for the planned E-ELT. Other sites that were under discussion included Cerro Macon, Salta, in Argentina, Roque de los Muchachos Observatory, on the Canary Islands, and sites in South Africa, Morocco, and Antarctica. Early designs included a primary mirror with a diameter of 42 metres and area of about 1,300 m2. However, in 2011 a proposal was put forward to reduce its size by 13% to 978 m2, for a 39.3 m diameter primary mirror and a 4.2 m diameter secondary mirror. It reduced projected costs from 1.275 billion to 1.055 billion euros, the ESO Council endorsed the revised baseline design in June 2011 and expected a construction proposal for approval in December 2011. Funding was subsequently included in the 2012 budget for initial work to begin in early 2012, the project received preliminary approval in June 2012. ESO approved the start of construction in December 2014, with over 90% funding of the nominal budget secured, the design phase of the 5-mirror anastigmat was fully funded within the ESO budget. With the 2011 changes in the design, the construction cost was estimated to be €1.055 billion. The start of operations is planned for 2024, the ESO focused on the current design after a feasibility study concluded the proposed 100 metres diameter Overwhelmingly Large Telescope would cost €1.5 billion, and be too complex. Both current fabrication technology and road transportation constraints limit single mirrors to being roughly 8 metres in a single piece, the E-ELT will use a similar design, as well as techniques to work around atmospheric distortion of incoming light, known as adaptive optics. A 40-metre-class mirror will allow the study of the atmospheres of extrasolar planets. The E-ELT is the highest priority in the European planning activities for research infrastructures, such as the Astronet Science Vision and Infrastructure Roadmap, the first three mirrors are curved, and form a three mirror anastigmat design for excellent image quality over the 10 arcminute field of view. The fourth and fifth mirrors are flat, and provide adaptive optics correction for atmospheric distortions, the surface of the 39-metre primary mirror will be composed of 798 hexagonal segments. In January 2017, ESO awarded the contract for the fabrication of the 4608 edge sensors to the FAMES consortium and these sensors can measure relative positions to an accuracy of a few nanometres, the most accurate ever used in a telescope
10.
Cerro Armazones
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Cerro Armazones is a mountain located in the Sierra Vicuña Mackenna of the Chilean Coast Range, approximately 130 km south-east of Antofagasta in the Antofagasta Region, Chile. Before the construction of the European Extremely Large Telescope started the summit was a control point with an elevation of 3,064 metres. It is located in a zone for optical astronomy because it has 89% cloudless nights a year. It currently hosts the 1.5 m Hexapod-Telescope and other telescopes at the Cerro Armazones Observatory, on 26 April 2010, the European Southern Observatory Council selected Cerro Armazones as the site for the planned European Extremely Large Telescope. Birds view on Cerro Paranal and Cerro Armazones
11.
Light
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Light is electromagnetic radiation within a certain portion of the electromagnetic spectrum. The word usually refers to light, which is visible to the human eye and is responsible for the sense of sight. Visible light is defined as having wavelengths in the range of 400–700 nanometres, or 4.00 × 10−7 to 7.00 × 10−7 m. This wavelength means a range of roughly 430–750 terahertz. The main source of light on Earth is the Sun, sunlight provides the energy that green plants use to create sugars mostly in the form of starches, which release energy into the living things that digest them. This process of photosynthesis provides virtually all the used by living things. Historically, another important source of light for humans has been fire, with the development of electric lights and power systems, electric lighting has effectively replaced firelight. Some species of animals generate their own light, a process called bioluminescence, for example, fireflies use light to locate mates, and vampire squids use it to hide themselves from prey. Visible light, as all types of electromagnetic radiation, is experimentally found to always move at this speed in a vacuum. In physics, the term sometimes refers to electromagnetic radiation of any wavelength. In this sense, gamma rays, X-rays, microwaves and radio waves are also light, like all types of light, visible light is emitted and absorbed in tiny packets called photons and exhibits properties of both waves and particles. This property is referred to as the wave–particle duality, the study of light, known as optics, is an important research area in modern physics. Generally, EM radiation, or EMR, is classified by wavelength into radio, microwave, infrared, the behavior of EMR depends on its wavelength. Higher frequencies have shorter wavelengths, and lower frequencies have longer wavelengths, when EMR interacts with single atoms and molecules, its behavior depends on the amount of energy per quantum it carries. There exist animals that are sensitive to various types of infrared, infrared sensing in snakes depends on a kind of natural thermal imaging, in which tiny packets of cellular water are raised in temperature by the infrared radiation. EMR in this range causes molecular vibration and heating effects, which is how these animals detect it, above the range of visible light, ultraviolet light becomes invisible to humans, mostly because it is absorbed by the cornea below 360 nanometers and the internal lens below 400. Furthermore, the rods and cones located in the retina of the eye cannot detect the very short ultraviolet wavelengths and are in fact damaged by ultraviolet. Many animals with eyes that do not require lenses are able to detect ultraviolet, by quantum photon-absorption mechanisms, various sources define visible light as narrowly as 420 to 680 to as broadly as 380 to 800 nm
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