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61-505: The Five-hundred-meter Aperture Spherical Telescope ( FAST ; Chinese : 五百米口径球面射电望远镜 ), nicknamed Tianyan ( 天眼 , lit. "Sky's/Heaven's Eye"), is a radio telescope located in the Dawodang depression ( 大窝凼洼地 ), a natural basin in Pingtang County , Guizhou , southwest China . FAST has a 500 m (1,640 ft) diameter dish constructed in a natural depression in the landscape. It

122-435: A Stewart platform which provides fine position control and compensates for disturbances like wind motion. This produces a planned pointing precision of 8 arcseconds . The maximum zenith angle is 40 degrees when the effective illuminated aperture is reduced to 200 m, while it is 26.4 degrees when the effective illuminated aperture is 300 m without loss. Although the reflector diameter is 500 m (1,600 ft), held in

183-443: A component—either a character or a sub-component called a radical —usually involves either a reduction in its total number of strokes , or an apparent streamlining of which strokes are chosen in what places—for example, the ⼓   ' WRAP ' radical used in the traditional character 沒 is simplified to ⼏   ' TABLE ' to form the simplified character 没 . By systematically simplifying radicals, large swaths of

244-434: A conversion table. While exercising such derivation, the following rules should be observed: Sample Derivations : The Series One List of Variant Characters reduces the number of total standard characters. First, amongst each set of variant characters sharing identical pronunciation and meaning, one character (usually the simplest in form) is elevated to the standard character set, and the rest are made obsolete. Then amongst

305-407: A few revised forms, and was implemented for official use by China's State Council on 5 June 2013. In Chinese, simplified characters are referred to by their official name 简化字 ; jiǎnhuàzì , or colloquially as 简体字 ; jiǎntǐzì . The latter term refers broadly to all character variants featuring simplifications of character form or structure, a practice which has always been present as

366-427: A fixed spherical shape with two additional suspended reflectors in a Gregorian configuration to correct for spherical aberration . Second, Arecibo's receiver platform was fixed in place. To support the greater weight of the additional reflectors, the primary support cables were static, with the only motorised portion being three hold-down winches which compensated for thermal expansion . The antennas could move along

427-415: A movable receiver suspended above; and both have an effective aperture smaller than the physical size of the primary. There are however significant differences in addition to the size. First, Arecibo's dish was fixed in a spherical shape. Although it was also suspended from steel cables with supports underneath for fine-tuning the shape, they were manually operated and adjusted only during maintenance. It had

488-599: A newly coined phono-semantic compound : Removing radicals Only retaining single radicals Replacing with ancient forms or variants : Adopting ancient vulgar variants : Readopting abandoned phonetic-loan characters : Copying and modifying another traditional character : Based on 132 characters and 14 components listed in Chart 2 of the Complete List , the 1,753 derived characters found in Chart 3 can be created by systematically simplifying components using Chart 2 as

549-478: A parabola, and thus the shortest wavelength it can focus. Arecibo's more rigid design allowed it to maintain sharp focus down to 3 cm wavelength (10 GHz); FAST is limited to 10 cm (3 GHz). Improvements in position control of the secondary might be able to push that to 6 cm (5 GHz), but then the primary reflector becomes a hard limit. Fourth, the FAST dish is significantly deeper, contributing to

610-568: A part of the Chinese writing system. The official name tends to refer to the specific, systematic set published by the Chinese government, which includes not only simplifications of individual characters, but also a substantial reduction in the total number of characters through the merger of formerly distinct forms. According to Chinese palaeographer Qiu Xigui , the broadest trend in the evolution of Chinese characters over their history has been simplification, both in graphical shape ( 字形 ; zìxíng ),

671-520: A receiver in a bistatic radar system. (Arecibo has been used in several multi-static experiments with an auxiliary 100 meter dish, including S-band radar experiments in the stratosphere, and ISAR mapping of Venus.) Simplified Chinese characters Simplified Chinese characters are one of two standardized character sets widely used to write the Chinese language , with the other being traditional characters . Their mass standardization during

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732-419: A reflecting surface 500 metres (1,600 ft) in diameter located in a natural sinkhole in the karst rock landscape , focusing radio waves on a receiving antenna in a "feed cabin" suspended 140 m (460 ft) above it. The reflector is made of perforated aluminium panels supported by a mesh of steel cables hanging from the rim. FAST's surface is made of 4,450 triangular panels, 11 m (36 ft) on

793-404: A rotating arm below the platform, to allow limited adjustment of azimuth, although Arecibo was not limited in azimuth, only in zenith angle: The smaller range of motion limited it to viewing objects within 19.7° of the zenith. Third, Arecibo could receive higher frequencies. The finite size of the triangular panels making up FAST's primary reflector limits the accuracy with which it can approximate

854-434: A side, in the form of a geodesic dome . There are 2,225 winches located underneath make it an active surface , pulling on joints between panels, deforming the flexible steel cable support into a parabolic antenna aligned with the desired sky direction. Above the reflector is a lightweight feed cabin moved by a cable robot using winch servomechanisms on six support towers. The receiving antennas are mounted below this on

915-493: A wider field of view. Although 64% larger in diameter, FAST's radius of curvature is 300 m (980 ft), barely larger than Arecibo's 270 m (870 ft), so it forms a 113° arc (vs. 70° for Arecibo). Although Arecibo's full aperture of 305 m (1,000 ft) could be used when observing objects at the zenith , this was only possible with the line feed which had a very narrow frequency range and had been unavailable due to damage since 2017. Most Arecibo observations used

976-440: Is actually more complex than eliminated ones. An example is the character 搾 which is eliminated in favor of the variant form 榨 . The 扌   'HAND' with three strokes on the left of the eliminated 搾 is now seen as more complex, appearing as the ⽊   'TREE' radical 木 , with four strokes, in the chosen variant 榨 . Not all characters standardised in the simplified set consist of fewer strokes. For instance,

1037-455: Is brought to its design accuracy; longer wavelengths are less sensitive to errors in reflector shape. It took three years to calibrate the various instruments so it can become fully operational. Local government efforts to develop a tourist industry around the telescope are causing some concern among astronomers worried about nearby mobile telephones acting as sources of RFI. A projected 10 million tourists in 2017 will force officials to decide on

1098-454: Is derived. Merging homophonous characters: Adapting cursive shapes ( 草書楷化 ): Replacing a component with a simple arbitrary symbol (such as 又 and 乂 ): Omitting entire components : Omitting components, then applying further alterations : Structural changes that preserve the basic shape Replacing the phonetic component of phono-semantic compounds : Replacing an uncommon phonetic component : Replacing entirely with

1159-809: Is now discouraged. A State Language Commission official cited "oversimplification" as the reason for restoring some characters. The language authority declared an open comment period until 31 August 2009, for feedback from the public. In 2013, the List of Commonly Used Standard Chinese Characters was published as a revision of the 1988 lists; it included a total of 8105 characters. It included 45 newly recognized standard characters that were previously considered variant forms, as well as official approval of 226 characters that had been simplified by analogy and had seen wide use but were not explicitly given in previous lists or documents. Singapore underwent three successive rounds of character simplification , eventually arriving at

1220-609: Is referred to as the " big seal script ". The traditional narrative, as also attested in the Shuowen Jiezi dictionary ( c.  100 AD ), is that the Qin small seal script that would later be imposed across China was originally derived from the Zhou big seal script with few modifications. However, the body of epigraphic evidence comparing the character forms used by scribes gives no indication of any real consolidation in character forms prior to

1281-452: Is the world's largest filled-aperture radio telescope and the second-largest single-dish aperture, after the sparsely-filled RATAN-600 in Russia. It has a novel design, using an active surface made of 4,500 metal panels which form a moving parabola shape in real time. The cabin containing the feed antenna , suspended on cables above the dish, can move automatically by using winches to steer

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1342-540: Is used instead of 叠 in regions using traditional characters. The Chinese government stated that it wished to keep Chinese orthography stable. The Chart of Generally Utilized Characters of Modern Chinese was published in 1988 and included 7000 simplified and unsimplified characters. Of these, half were also included in the revised List of Commonly Used Characters in Modern Chinese , which specified 2500 common characters and 1000 less common characters. In 2009,

1403-582: The "Dot" stroke : The traditional components ⺥ and 爫 become ⺈ : The traditional component 奐 becomes 奂 : Dan Werthimer Werthimer was associate professor in the engineering and physics departments of San Francisco State University and a visiting professor at Beijing Normal University, the University of St. Charles in Marseille, Eotvos University in Budapest. His father, Jerrold Werthimer ,

1464-456: The "external appearances of individual graphs", and in graphical form ( 字体 ; 字體 ; zìtǐ ), "overall changes in the distinguishing features of graphic[al] shape and calligraphic style, [...] in most cases refer[ring] to rather obvious and rather substantial changes". The initiatives following the founding of the Qin dynasty (221–206 BC) to universalize the use of their small seal script across

1525-476: The 1986 General List of Simplified Chinese Characters , hereafter the General List . All characters simplified this way are enumerated in Chart 1 and Chart 2 in the 1986 Complete List . Characters in both charts are structurally simplified based on similar set of principles. They are separated into two charts to clearly mark those in Chart 2 as 'usable as simplified character components', based on which Chart 3

1586-508: The 1986 mainland China revisions. Unlike in mainland China, Singapore parents have the option of registering their children's names in traditional characters. Malaysia also promulgated a set of simplified characters in 1981, though completely identical to the mainland Chinese set. They are used in Chinese-language schools. All characters simplified this way are enumerated in Charts 1 and 2 of

1647-502: The 20th century was part of an initiative by the People's Republic of China (PRC) to promote literacy, and their use in ordinary circumstances on the mainland has been encouraged by the Chinese government since the 1950s. They are the official forms used in mainland China and Singapore , while traditional characters are officially used in Hong Kong , Macau , and Taiwan . Simplification of

1708-470: The Chinese government published a major revision to the list which included a total of 8300 characters. No new simplifications were introduced. In addition, slight modifications to the orthography of 44 characters to fit traditional calligraphic rules were initially proposed, but were not implemented due to negative public response. Also, the practice of unrestricted simplification of rare and archaic characters by analogy using simplified radicals or components

1769-957: The Gregorian feeds, where the effective aperture was approximately 221 m (725 ft) at zenith. Fifth, Arecibo's larger secondary platform also housed several transmitters , making it one of the few instruments in the world capable of radar astronomy . (Planetary radar is also possible at the Jicamarca and Millstone and Altair observatories.) The NASA-funded Planetary Radar System allowed Arecibo to study solid objects from Mercury to Saturn, and to perform very accurate orbit determination on near-earth objects , particularly potentially hazardous objects . Arecibo also included several NSF funded radars for ionospheric studies ( ionosondes ). Such powerful transmitters are too large and heavy for FAST's small receiver cabin, so it will not be able to participate in planetary defense although in principle it could serve as

1830-428: The character set are altered. Some simplifications were based on popular cursive forms that embody graphic or phonetic simplifications of the traditional forms. In addition, variant characters with identical pronunciation and meaning were reduced to a single standardized character, usually the simplest among all variants in form. Finally, many characters were left untouched by simplification and are thus identical between

1891-407: The chosen variants, those that appear in the "Complete List of Simplified Characters" are also simplified in character structure accordingly. Some examples follow: Sample reduction of equivalent variants : Ancient variants with simple structure are preferred : Simpler vulgar forms are also chosen : The chosen variant was already simplified in Chart 1 : In some instances, the chosen variant

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1952-534: The correct parabolic shape and "illuminated" by the receiver, only a circle of 300 m diameter is useful at any one time. The telescope can be pointed to different positions on the sky by illuminating a 300-meter section of the 500 meter aperture. (FAST has a smaller effective aperture than the Jicamarca Radio Observatory , which has a filled aperture of equivalent diameter of 338 m). Its working frequency ranges from 70 MHz to 3.0  GHz , with

2013-465: The country's writing system as a serious impediment to its modernization. In 1916, a multi-part English-language article entitled "The Problem of the Chinese Language" co-authored by the Chinese linguist Yuen Ren Chao (1892–1982) and poet Hu Shih (1891–1962) has been identified as a turning point in the history of the Chinese script—as it was one of the first clear calls for China to move away from

2074-521: The discoveries on 10 September 2017. By September 2018, FAST had discovered 44 new pulsars, and by 2021, 500. The telescope was first proposed in 1994. The project was approved by the National Development and Reform Commission (NDRC) in July 2007. A 65-person village was relocated from the valley to make room for the telescope and an additional 9,110 people living within a 5 km (3 mi) radius of

2135-472: The early 20th century. In 1909, the educator and linguist Lufei Kui formally proposed the use of simplified characters in education for the first time. Over the following years—marked by the 1911 Xinhai Revolution that toppled the Qing dynasty , followed by growing social and political discontent that further erupted into the 1919 May Fourth Movement —many anti-imperialist intellectuals throughout China began to see

2196-616: The first official list of simplified forms was published, consisting of 324 characters collated by Peking University professor Qian Xuantong . However, fierce opposition within the KMT resulted in the list being rescinded in 1936. Work throughout the 1950s resulted in the 1956 promulgation of the Chinese Character Simplification Scheme , a draft of 515 simplified characters and 54 simplified components, whose simplifications would be present in most compound characters. Over

2257-710: The first pulsar discovery from FAST. At the moment, only the FAST L-band Receiver-array of 19 beams (FLAN) is installed and is operational between 1.05 GHz and 1.45 GHz. The Next Generation Archive System (NGAS), developed by the International Centre for Radio Astronomy Research (ICRAR) in Perth, Australia and the European Southern Observatory will store and maintain the large amount of data that it collects. A five-kilometre zone near

2318-463: The first round—but was massively unpopular and never saw consistent use. The second round of simplifications was ultimately retracted officially in 1986, well after they had largely ceased to be used due to their unpopularity and the confusion they caused. In August 2009, China began collecting public comments for a revised list of simplified characters; the resulting List of Commonly Used Standard Chinese Characters lists 8,105 characters, including

2379-465: The following decade, the Script Reform Committee deliberated on characters in the 1956 scheme, collecting public input regarding the recognizability of variants, and often approving forms in small batches. Parallel to simplification, there were also initiatives aimed at eliminating the use of characters entirely and replacing them with pinyin as an official Chinese alphabet, but this possibility

2440-503: The founding of the Qin. The Han dynasty (202 BC – 220 AD) that inherited the Qin administration coincided with the perfection of clerical script through the process of libian . Eastward spread of Western learning Though most closely associated with the People's Republic, the idea of a mass simplification of character forms first gained traction in China during

2501-466: The increased usage of 朙 was followed by proliferation of a third variant: 眀 , with 目 'eye' on the left—likely derived as a contraction of 朙 . Ultimately, 明 became the character's standard form. The Book of Han (111 AD) describes an earlier attempt made by King Xuan of Zhou ( d.  782 BC ) to unify character forms across the states of ancient China , with his chief chronicler having "[written] fifteen chapters describing" what

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2562-793: The instrument to receive signals from different directions. It observes at wavelengths of 10 cm to 4.3 m. Construction of FAST began in 2011. It observed first light in September 2016. After three years of testing and commissioning, it was declared fully operational on 11 January 2020. The telescope made its first discovery, of two new pulsars , in August 2017. The new pulsars PSR J1859-01 and PSR J1931-02—also referred to as FAST pulsar #1 and #2 (FP1 and FP2), were detected on 22 and 25 August 2017; they are 16,000 and 4,100 light years away, respectively. Parkes Observatory in Australia independently confirmed

2623-459: The left, with the 月 'Moon' component on the right. Li Si ( d.  208 BC ), the Chancellor of Qin, attempted to universalize the Qin small seal script across China following the wars that had politically unified the country for the first time. Li prescribed the 朙 form of the word for 'bright', but some scribes ignored this and continued to write the character as 明 . However,

2684-402: The most prominent Chinese authors of the 20th century, stated that "if Chinese characters are not destroyed, then China will die" ( 漢字不滅，中國必亡 ). During the 1930s and 1940s, discussions regarding simplification took place within the ruling Kuomintang (KMT) party. Many members of the Chinese intelligentsia maintained that simplification would increase literacy rates throughout the country. In 1935,

2745-424: The possibility of having detected artificial (presumably alien) signals, but cautioned that further studies are required to determine if some kind of natural radio interference may be the source. More recently, on 18 June 2022, Dan Werthimer , chief scientist for several SETI -related projects, noted, "These signals are from radio interference; they are due to radio pollution from earthlings, not from E.T." FAST has

2806-430: The public and quickly fell out of official use. It was ultimately formally rescinded in 1986. The second-round simplifications were unpopular in large part because most of the forms were completely new, in contrast to the familiar variants comprising the majority of the first round. With the rescission of the second round, work toward further character simplification largely came to an end. In 1986, authorities retracted

2867-465: The recently conquered parts of the empire is generally seen as being the first real attempt at script reform in Chinese history. Before the 20th century, variation in character shape on the part of scribes, which would continue with the later invention of woodblock printing , was ubiquitous. For example, prior to the Qin dynasty (221–206 BC) the character meaning 'bright' was written as either 明 or 朙 —with either 日 'Sun' or 囧 'window' on

2928-476: The same set of simplified characters as mainland China. The first round was promulgated by the Ministry of Education in 1969, consisting of 498 simplified characters derived from 502 traditional characters. A second round of 2287 simplified characters was promulgated in 1974. The second set contained 49 differences from the mainland China system; these were removed in the final round in 1976. In 1993, Singapore adopted

2989-641: The scientific mission versus the economic benefits of tourism. The primary driving force behind the project was Nan Rendong , a researcher with the Chinese National Astronomical Observatory , part of the Chinese Academy of Sciences . He held the positions of chief scientist and chief engineer of the project. He died on 15 September 2017 in Boston due to lung cancer. On 14 June 2022, astronomers, working with China's FAST telescope, reported

3050-461: The second round completely, though they had been largely fallen out of use within a year of their initial introduction. That year, the authorities also promulgated a final version of the General List of Simplified Chinese Characters . It was identical to the 1964 list save for 6 changes—including the restoration of 3 characters that had been simplified in the first round: 叠 , 覆 , 像 ; the form 疊

3111-572: The telescope forbids tourists from using mobile phones and other radio-emitting devices. The FAST website lists the following science objectives of the radio telescope: The FAST telescope joined the Breakthrough Listen SETI project in October 2016 to search for intelligent extraterrestrial communications in the Universe. In February 2020, scientists announced the first SETI observations with

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3172-451: The telescope were relocated to create a radio-quiet area . The Chinese government spent around US$ 269 million in poverty relief funds and bank loans for the relocation of the local residents, while the construction of the telescope itself cost $ 180 million. On 26 December 2008, a foundation-laying ceremony was held on the construction site. Construction started in March 2011, and the last panel

3233-600: The telescope. China's Global Times reported that its 500-meter (1,600 foot) FAST telescope will be open to the global scientific community starting in April 2021 (when applications will be reviewed), and becoming effective in August 2021. Foreign scientists will be able to submit applications to China's National Astronomical Observatories online. The basic design of FAST is similar to the former Arecibo Telescope . Both designs had reflectors installed in natural hollows within karst limestone, made of perforated aluminium panels with

3294-488: The traditional and simplified Chinese orthographies. The Chinese government has never officially announced the completion of the simplification process after the bulk of characters were introduced by the 1960s. In the wake of the Cultural Revolution , a second round of simplified characters was promulgated in 1977—largely composed of entirely new variants intended to artificially lower the stroke count, in contrast to

3355-817: The traditional character 強 , with 11 strokes is standardised as 强 , with 12 strokes, which is a variant character. Such characters do not constitute simplified characters. The new standardized character forms shown in the Characters for Publishing and revised through the Common Modern Characters list tend to adopt vulgar variant character forms. Since the new forms take vulgar variants, many characters now appear slightly simpler compared to old forms, and as such are often mistaken as structurally simplified characters. Some examples follow: The traditional component 釆 becomes 米 : The traditional component 囚 becomes 日 : The traditional "Break" stroke becomes

3416-431: The upper limit set by the precision with which the primary can approximate a parabola. It could be improved slightly, but the size of the triangular segments limits the shortest wavelength which can be received. The original plan was to cover the frequency range with 9 receivers. During the construction phase, a commissioning ultra-wide band receiver covering 260 MHz to 1620 MHz was proposed and built, which produced

3477-516: The use of characters entirely. Instead, Chao proposed that the language be written with an alphabet, which he saw as more logical and efficient. The alphabetization and simplification campaigns would exist alongside one another among the Republican intelligentsia for the next several decades. Recent commentators have echoed some contemporary claims that Chinese characters were blamed for the economic problems in China during that time. Lu Xun , one of

3538-507: Was Professor of Journalism at San Francisco State University for many years. Werthimer has taught courses at universities in Peru, Egypt, Ghana, Ethiopia, Zimbabwe, Uganda and Kenya. He has published numerous papers in the fields of SETI, radio astronomy, instrumentation and science education; he is co-author of "SETI 2020" and editor of "Astronomical and Biochemical Origins and the Search for Life in

3599-461: Was abandoned, confirmed by a speech given by Zhou Enlai in 1958. In 1965, the PRC published the List of Commonly Used Characters for Printing  [ zh ] (hereafter Characters for Printing ), which included standard printed forms for 6196 characters, including all of the forms from the 1956 scheme. A second round of simplified characters was promulgated in 1977, but was poorly received by

3660-449: Was completed in 2015. Interference from the actuators has not been detected since. Testing and commissioning began with first light on 25 September 2016. The first observations are being done without the active primary reflector, configuring it in a fixed shape and using the Earth's rotation to scan the sky. Subsequent early science took place mainly in lower frequencies while the active surface

3721-442: Was installed on the morning of 3 July 2016. Originally budgeted for CN¥ 700 million, the final cost was CN¥1.2 billion ( US$ 180 million ). Significant difficulties encountered were the site's remote location and poor road access, and the need to add shielding to suppress radio-frequency interference (RFI) from the primary mirror actuators. The actuators were redesigned to meet shielding efficiency requirements and their installation

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