Search This Blog

Sunday, October 29, 2023

History of writing

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/History_of_writing

History of writing
Historical Writing Systems Template Image
Six major historical writing systems (left to right, top to bottom: Sumerian pictographs, Egyptian hieroglyphs, Chinese syllabograms, Old Persian cuneiform, Roman alphabet, Indian Devanagari)

The history of writing traces the development of expressing language by systems of markings and how these markings were used for various purposes in different societies, thereby transforming social organization. Writing systems are the foundation of literacy and literacy learning, with all the social and psychological consequences associated with literacy activities.

In the history of how writing systems have evolved in human civilizations, more complete writing systems were preceded by proto-writing, systems of ideographic or early mnemonic symbols (symbols or letters that make remembering them easier). True writing, in which the content of a linguistic utterance is encoded so that another reader can reconstruct, with a fair degree of accuracy, the exact utterance written down, is a later development. It is distinguished from proto-writing, which typically avoids encoding grammatical words and affixes, making it more difficult or even impossible to reconstruct the exact meaning intended by the writer unless a great deal of context is already known in advance.

The earliest uses of writing in Sumer were to document agricultural produce and create contracts, but soon writing became used for purposes of finances, religion, government, and law. These uses supported the spread of these social activities, their associated knowledge, and the extension of centralized power. Writing then became the basis of knowledge institutions such as libraries, schools, universities and scientific and disciplinary research. These uses were accompanied by the proliferation of genres, which typically initially contained markers or reminders of the social situations and uses, but the social meaning and implications of genres often became more implicit as the social functions of these genres became more recognizable in themselves, as in the examples of money, currency, financial instruments, and now digital currency.

Writing systems


Clay bulla and tokens, 4000–3100 BCE, Susa
 
Numerical tablet, 3500-3350 BCE (Uruk V phase), Khafajah
 
Pre-cuneiform tags, with drawing of goat or sheep and number (probably "10"), Al-Hasakah, 3300–3100 BCE, Uruk culture

Writing systems typically satisfy three criteria: firstly, writing must be complete with a purpose or some sort of meaning to it, and a point must be made or communicated in the text; secondly, all writing systems must have a set of symbols which can be made on some sort of writing material, whether physical or digital; thirdly, the symbols used in the writing system usually mimic spoken word/speech in order for communication to be possible. Symbolic communication systems are distinguished from writing systems. With writing systems, one must usually understand something of the associated spoken language to comprehend the text. In contrast, symbolic systems, such as information signs, painting, maps, and mathematics, often do not require prior knowledge of a spoken language.

Early Proto-cuneiform (4th millennium BCE) and cuneiform signs for the sexagesimal system (60, 600, 3600, etc.).

Every human community possesses language; although the origin of language is disputed, it is often regarded as an innate and defining condition of humanity. However, the development of writing systems and their partial replacement of traditional oral systems of communication have been sporadic, uneven, and slow. Once established, writing systems on the whole change more slowly than their spoken counterparts and often preserve features and expressions that no longer exist in the spoken language. The greatest benefit of writing is that it provides the tool by which society can record information consistently and in greater detail, something that could not be achieved as well previously by spoken word. Writing allows societies to transmit information and to share and preserve knowledge.

Recorded history of writing

Art of Lascaux, with painted animal, and four dots, a possible notation for Lunar months.

Some notational signs, used next to images of animals, may have appeared as early as the Upper Palaeolithic in Europe circa 35,000 BCE, and may be the earliest proto-writing: several symbols were used in combination as a way to convey seasonal behavioural information about hunted animals.

The origins of writing are more generally attributed to the start of the pottery-phase of the Neolithic, when clay tokens were used to record specific amounts of livestock or commodities. These tokens were initially impressed on the surface of round clay envelopes and then stored in them. The tokens were then progressively replaced by flat tablets, on which signs were recorded with a stylus. Actual writing is first recorded in Uruk, at the end of the 4th millennium BCE, and soon after in various parts of the Near East.

An ancient Mesopotamian poem gives the first known story of the invention of writing:

The Kish tablet from Sumer, with pictographic writing. This may be the earliest known writing, 3500 BCE. Ashmolean Museum

Because the messenger's mouth was heavy and he couldn't repeat (the message), the Lord of Kulaba patted some clay and put words on it, like a tablet. Until then, there had been no putting words on clay.

— Sumerian epic poem Enmerkar and the Lord of Aratta. c. 1800 BCE.

Scholars make a reasonable distinction between prehistory and history of early writing but have disagreed concerning when prehistory becomes history and when proto-writing became "true writing". The definition is largely subjective. Writing, in its most general terms, is a method of recording information and is composed of graphemes, which may, in turn, be composed of glyphs.

The emergence of writing in a given area is usually followed by several centuries of fragmentary inscriptions. Historians mark the "historicity" of a culture by the presence of coherent texts in the culture's writing system(s).

Inventions of writing

Sumer, an ancient civilization of southern Mesopotamia, is believed to be the place where written language was first invented around 3200 BCE

Writing was long thought to have been invented in a single civilization, a theory named "monogenesis". Scholars believed that all writing originated in ancient Sumer (in Mesopotamia) and spread over the world from there via a process of cultural diffusion. According to this theory, the concept of representing language by written marks, though not necessarily the specifics of how such a system worked, was passed on by traders or merchants traveling between geographical regions.

However, non-Mesoamerican scholars eventually learned of the scripts of ancient Mesoamerica, far away from Middle Eastern sources, proving to them that writing had been invented more than once. Scholars now recognize that writing may have independently developed in at least four ancient civilizations: Mesopotamia (between 3400 and 3100 BCE), Egypt (around 3250 BCE), China (1200 BCE), and lowland areas of Mesoamerica (by 500 BCE).

Regarding ancient Egypt, it was once believed the Egyptians had learned the idea of writing from Sumerians. However, several scholars have argued that "the earliest solid evidence of Egyptian writing differs in structure and style from the Mesopotamian and must therefore have developed independently. The possibility of 'stimulus diffusion' from Mesopotamia remains, but the influence cannot have gone beyond the transmission of an idea."

Regarding China, it is believed that ancient Chinese characters are an independent invention because there is no evidence of contact between ancient China and the literate civilizations of the Near East, and because of the distinct differences between the Mesopotamian and Chinese approaches to logography and phonetic representation.

Debate surrounds the Indus script of the Bronze Age Indus Valley civilisation, the Rongorongo script of Easter Island, and the Vinča symbols dated around 5500 BCE. All are undeciphered, and so it is unknown if they represent authentic writing, proto-writing, or something else.

The Sumerian archaic (pre-cuneiform) writing and Egyptian hieroglyphs are generally considered the earliest true writing systems, both emerging out of their ancestral proto-literate symbol systems from 3400 to 3100 BCE, with earliest coherent texts from about 2600 BCE. The Proto-Elamite script is also dated to the same approximate period.

Developmental stages

Standard reconstruction of the development of writing. There is a possibility that the Egyptian script was invented independently from the Mesopotamian script. This diagram excludes the writing systems found in Mesoamerica by 500 BCE.
Comparative evolution from pictograms to abstract shapes, in Mesopotamian Cuneiform, Egyptian hieroglyphs and Chinese characters

A conventional "proto-writing to true writing" system follows a general series of developmental stages:

  • Picture writing system: glyphs (simplified pictures) directly represent objects and concepts. In connection with this, the following substages may be distinguished:
    • Mnemonic: glyphs primarily as a reminder.
    • Pictographic: glyphs directly represent an object or a concept such as (A) chronological, (B) notices, (C) communications, (D) totems, titles, and names, (E) religious, (F) customs, (G) historical, and (H) biographical.
    • Ideographic: graphemes are abstract symbols that directly represent an idea or concept.
  • Transitional system: graphemes refer not only to the object or idea that it represents but to its name as well.
  • Phonetic system: graphemes refer to sounds or spoken symbols, and the form of the grapheme is not related to its meanings. This resolves itself into the following substages:
    • Verbal: grapheme (logogram) represents a whole word.
    • Syllabic: grapheme represents a syllable.
    • Alphabetic: grapheme represents an elementary sound.

The best known picture writing system of ideographic or early mnemonic symbols are:

In the Old World, true writing systems developed from neolithic writing in the Early Bronze Age (4th millennium BCE).

Locations and timeframes

Examples of the Jiahu symbols, markings found on tortoise shells, dated around 6000 BCE. Most of the signs were separately inscribed on different shells.

Proto-writing

The first writing systems of the Early Bronze Age were not a sudden invention. Rather, they were a development based on earlier traditions of symbol systems that cannot be classified as proper writing, but have many of the characteristics of writing. These systems may be described as "proto-writing". They used ideographic or early mnemonic symbols to convey information, but it probably directly contained no natural language.

These systems emerged in the early Neolithic period, as early as the 7th millennium BCE, and include:

Even after the Neolithic, several cultures went through an intermediate stage of proto-writing before they used proper writing. The quipu of the Incas (15th century CE), sometimes called "talking knots", may have been such a system. Another example is the pictographs invented by Uyaquk before the development of the Yugtun syllabary for the Central Alaskan Yup'ik language in about 1900.

Bronze Age writing

Writing emerged in many different cultures in the Bronze Age. Examples are the cuneiform writing of Sumer, Egyptian hieroglyphs, Cretan hieroglyphs, Chinese logographs, Indus script, and the Olmec hieroglyphs of pre-Columbian era Mesoamerica. Chinese characters likely developed independently of the Middle Eastern scripts around 1600 BCE. The Mesoamerican writing systems (including Olmec and the Maya script) are also generally believed to have had independent origins.

It is thought that the first true alphabetic writing was developed around 2000 BCE for Semitic-speaking workers in the Sinai Peninsula by giving Egyptian Hieratic letters Semitic values (see history of the alphabet and Proto-Sinaitic script). The Geʽez script of Ethiopia and Eritrea is an evolution of the Ancient South Arabian script, in which early Geʽez texts were originally written.

Most other alphabets in the world today either descended from this one innovation, many via the Phoenician alphabet, or were directly inspired by its design. In Italy, about 500 years passed from the early Old Italic scripts to Plautus (c. 750–250 BCE), and in the case of the Germanic peoples, the corresponding time span is again similar, from the first Elder Futhark inscriptions to early texts like the Abrogans (c. 200–750 CE).

Cuneiform script

Tablet with proto-cuneiform pictographic characters (end of 4th millennium BCE), Uruk III

The original Sumerian writing system derives from a system of clay tokens used to represent commodities. By the end of the 4th millennium BCE, this had evolved into a method of keeping accounts, using a round-shaped stylus impressed into soft clay at different angles for recording numbers. This was gradually augmented with pictographic writing by using a sharp stylus to indicate what was being counted. By the 29th century BCE, writing, at first only for logograms, using a wedge-shaped stylus (hence the term cuneiform) developed to include phonetic elements, gradually replacing round-stylus and sharp-stylus writing by around 2700–2500 BCE. About 2600 BCE, cuneiform began to represent syllables of the Sumerian language. Finally, cuneiform writing became a general purpose writing system for logograms, syllables, and numbers. From the 26th century BCE, this script was adapted to the Akkadian language, and from there to others, such as Hurrian and Hittite. Scripts similar in appearance to this writing system include those for Ugaritic and Old Persian.

Egyptian hieroglyphs

Designs on some of the labels or tokens from Abydos, carbon-dated to circa 3400–3200 BCE and among the earliest form of writing in Egypt. They are remarkably similar to contemporary clay tags from Uruk, Mesopotamia.

Writing was very important in maintaining the Egyptian empire, and literacy was concentrated among an educated elite of scribes. Only people from certain backgrounds were allowed to train as scribes, in the service of temple, royal (pharaonic), and military authorities.

Geoffrey Sampson stated that Egyptian hieroglyphs "came into existence a little after Sumerian script, and, probably [were], invented under the influence of the latter", and that it is "probable that the general idea of expressing words of a language in writing was brought to Egypt from Sumerian Mesopotamia". Despite the importance of early Egypt–Mesopotamia relations, given the lack of direct evidence "no definitive determination has been made as to the origin of hieroglyphics in ancient Egypt". Instead, it is pointed out and held that "the evidence for such direct influence remains flimsy" and that "a very credible argument can also be made for the independent development of writing in Egypt".

Since the 1990s, the discoveries of glyphs at Abydos, dated to between 3400 and 3200 BCE, may challenge the classical notion according to which the Mesopotamian symbol system predates the Egyptian one, although Egyptian writing does make a sudden appearance at that time, while on the contrary Mesopotamia has an evolutionary history of sign usage in tokens dating back to circa 8000 BCE. These glyphs, found in tomb U-J at Abydos are written on ivory and are likely labels for other goods found in the grave.

Frank Yurco stated that depictions of pharaonic iconography such as the royal crowns, Horus falcons and victory scenes were concentrated in the Upper Egyptian Naqada culture and A-Group Nubia. He further elaborated that "Egyptian writing arose in Naqadan Upper Egypt and A-Group Nubia, and not in the Delta cultures, where the direct Western Asian contact was made, [which] further vitiates the Mesopotamian-influence argument".

Egyptian scholar Gamal Mokhtar argued that the inventory of hieroglyphic symbols derived from "fauna and flora used in the signs [which] are essentially African" and in "regards to writing, we have seen that a purely Nilotic, hence African origin not only is not excluded, but probably reflects the reality" although he acknowledged the geographical location of Egypt made it a receptacle for many influences.

Elamite script

The undeciphered Proto-Elamite script emerges from as early as 3100 BCE. It is believed to have evolved into Linear Elamite by the later 3rd millennium and then replaced by Elamite Cuneiform adopted from Akkadian.

Indus script

Indus script tablet recovered from Khirasara, Indus Valley Civilization

Markings and symbols found at various sites of the Indus Valley Civilisation have been labelled as the Indus script citing the possibility that they were used for transcribing the Harappan language. Whether the script, which was in use from about 3500–1900 BCE, constitutes a Bronze Age writing script (logographic-syllabic) or proto-writing symbols is debated as it has not yet been deciphered. It is analyzed to have been written from right-to-left or in boustrophedon.

Early Semitic alphabets

The first "abjads", mapping single symbols to single phonemes but not necessarily each phoneme to a symbol, emerged around 1800 BCE in Ancient Egypt, as a representation of language developed by Semitic workers in Egypt, but by then alphabetic principles had a slight possibility of being inculcated into Egyptian hieroglyphs for upwards of a millennium. These early abjads remained of marginal importance for several centuries, and it is only towards the end of the Bronze Age that the Proto-Sinaitic script splits into the Proto-Canaanite alphabet (c. 1400 BCE) Byblos syllabary and the South Arabian alphabet (c. 1200 BCE). The Proto-Canaanite was probably somehow influenced by the undeciphered Byblos syllabary and, in turn, inspired the Ugaritic alphabet (c. 1300 BCE).

Anatolian hieroglyphs

Anatolian hieroglyphs are an indigenous hieroglyphic script native to western Anatolia, used to record the Hieroglyphic Luwian language. It first appeared on Luwian royal seals from the 14th century BCE.

Chinese writing

The earliest confirmed evidence of the Chinese script yet discovered is the body of inscriptions on oracle bones and bronze from the late Shang dynasty. The earliest of these is dated to around 1200 BCE.

There have recently been discoveries of tortoise-shell carvings dating back to c. 6000 BCE, like Jiahu Script, Banpo Script, but whether or not the carvings are complex enough to qualify as writing is under debate. At Damaidi in the Ningxia Hui Autonomous Region, 3,172 cliff carvings dating to c. 6000–5000 BCE have been discovered, featuring 8,453 individual characters, such as the sun, moon, stars, gods, and scenes of hunting or grazing. These pictographs are reputed to be similar to the earliest characters confirmed to be written Chinese. If it is deemed to be a written language, writing in China will predate Mesopotamian cuneiform, long acknowledged as the first appearance of writing, by some 2,000 years; however it is more likely that the inscriptions are rather a form of proto-writing, similar to the contemporary European Vinca script.

Cretan and Greek scripts

Cretan hieroglyphs are found on artifacts of Crete (early-to-mid-2nd millennium BCE, MM I to MM III, overlapping with Linear A from MM IIA at the earliest). Linear B, the writing system of the Mycenaean Greeks, has been deciphered while Linear A has yet to be deciphered. The sequence and the geographical spread of the three overlapping, but distinct, writing systems can be summarized as follows:

Writing system Geographical area Time span
Cretan Hieroglyphic Crete (eastward from the Knossos-Phaistos axis) c. 2100−1700 BCE
Linear A Crete (except extreme southwest), Aegean Islands (Kea, Kythera, Melos, Thera), and Greek mainland (Laconia) c. 1800−1450 BCE
Linear B Crete (Knossos), and mainland (Pylos, Mycenae, Thebes, Tiryns) c. 1450−1200 BCE

Mesoamerica

A stone slab with 3,000-year-old writing, the Cascajal Block, was discovered in the Mexican state of Veracruz, and is an example of the oldest script in the Western Hemisphere, preceding the oldest Zapotec writing dated to about 500 BCE.

Of several pre-Columbian scripts in Mesoamerica, the one that appears to have been best developed, and has been fully deciphered, is the Maya script. The earliest inscriptions which are identifiably Maya date to the 3rd century BCE, and writing was in continuous use until shortly after the arrival of the Spanish conquistadores in the 16th century CE. Maya writing used logograms complemented by a set of syllabic glyphs: a combination somewhat similar to modern Japanese writing.

Iron Age writing

The sculpture depicts a scene where three soothsayers are interpreting to King Suddhodana the dream of Queen Maya, mother of Gautama Buddha. Below them is seated a scribe recording the interpretation. From Nagarjunakonda, 2nd century CE. A child learning the Brahmi Alphabet is also known from the 2nd century BCE in Srughna.

The Phoenician alphabet is simply the Proto-Canaanite alphabet as it was continued into the Iron Age (conventionally taken from a cut-off date of 1050 BCE). This alphabet gave rise to the Aramaic and Greek alphabets. These in turn led to the writing systems used throughout regions ranging from Western Asia to Africa and Europe. For its part the Greek alphabet introduced for the first time explicit symbols for vowel sounds. The Greek and Latin alphabets in the early centuries of the Common Era gave rise to several European scripts such as the Runes and the Gothic and Cyrillic alphabets while the Aramaic alphabet evolved into the Hebrew, Arabic and Syriac abjads, of which the latter spread as far as Mongolian script. The South Arabian alphabet gave rise to the Ge'ez abugida. The Brahmic family of India is believed by some scholars to have derived from the Aramaic alphabet as well.

Grakliani Hill writing

A previously unknown script was discovered in 2015 in Georgia, over the Grakliani Hill just below a temple's collapsed altar to a fertility goddess from the seventh century BCE. These inscriptions differ from those at other temples at Grakliani, which show animals, people, or decorative elements. The script bears no resemblance to any alphabet currently known, although its letters are conjectured to be related to ancient Greek and Aramaic. The inscription appears to be the oldest native alphabet to be discovered in the whole Caucasus region, In comparison, the earliest Armenian and Georgian script date from the fifth century CE, just after the respective cultures converted to Christianity. By September 2015, an area of 31 by 3 inches of the inscription had been excavated.

According to Vakhtang Licheli, head of the Institute of Archaeology of the State University, "The writings on the two altars of the temple are really well preserved. On the one altar several letters are carved in clay while the second altar's pedestal is wholly covered with writings." The finding was made by unpaid students. In 2016 Grakliani Hill inscriptions were taken to Miami Laboratory for Beta analytic radiocarbon dating which found that the inscriptions were made in c. 1005 – c. 950 BCE.

Writing in the Greco-Roman civilizations

Early Greek alphabet on pottery in the National Archaeological Museum, Athens

Greek scripts

The history of the Greek alphabet began in at least the early 8th century BCE when the Greeks adapted the Phoenician alphabet for use with their own language. The letters of the Greek alphabet are more or less the same as those of the Phoenician alphabet, and in modern times both alphabets are arranged in the same order. The adapter(s) of the Phoenician system added three letters to the end of the series, called the "supplementals". Several varieties of the Greek alphabet developed. One, known as Western Greek or Chalcidian, was used west of Athens and in southern Italy. The other variation, known as Eastern Greek, was used in present-day Turkey and by the Athenians, and eventually the rest of the world that spoke Greek adopted this variation. After first writing right to left, like the Phoenicians, the Greeks eventually chose to write from left to right. Occasionally however, the writer would start the next line where the previous line finished, so that the lines would read alternately left to right, then right to left, and so on. This was known as "boustrophedon" writing, which imitated the path of an ox-drawn plough, and was used until the sixth century.

Italic scripts and Latin

Cippus Perusinus, Etruscan writing near Perugia, Italy, the precursor of the Latin alphabet

Greek is in turn the source for all the modern scripts of Europe. The most widespread descendant of Greek is the Latin script, named for the Latins, a central Italian people who came to dominate Europe with the rise of Rome. The Romans learned writing in about the 5th century BCE from the Etruscan civilization, who used one of a number of Italic scripts derived from the western Greeks. Due to the cultural dominance of the Roman state, the other Old Italic scripts have not survived in any great quantity, and the Etruscan language is mostly lost.

Writing during the Middle Ages

With the collapse of the Roman authority in Western Europe, literacy development became largely confined to the Eastern Roman Empire and the Persian Empire. Latin, never one of the primary literary languages, rapidly declined in importance (except within the Roman Catholic Church). The primary literary languages were Greek and Persian, though other languages such as Syriac and Coptic were important too.

The rise of Islam in the 7th century led to the rapid rise of Arabic as a major literary language in the region. Arabic and Persian quickly began to overshadow Greek's role as a language of scholarship. Arabic script was adopted as the primary script of the Persian language and the Turkish language. This script also heavily influenced the development of the cursive scripts of Greek, the Slavic languages, Latin, and other languages. The Arabic language also served to spread the Hindu–Arabic numeral system throughout Europe. By the beginning of the second millennium, the city of Córdoba in modern Spain had become one of the foremost intellectual centers of the world and contained the world's largest library at the time. Its position as a crossroads between the Islamic and Western Christian worlds helped fuel intellectual development and written communication between both cultures.

Renaissance and the modern era

By the 14th century a rebirth, or renaissance, had emerged in Western Europe, leading to a temporary revival of the importance of Greek, and a slow revival of Latin as a significant literary language. A similar though smaller emergence occurred in Eastern Europe, especially in Russia. At the same time Arabic and Persian began a slow decline in importance as the Islamic Golden Age ended. The revival of literacy development in Western Europe led to many innovations in the Latin alphabet and the diversification of the alphabet to codify the phonologies of the various languages.

The nature of writing has been constantly evolving, particularly due to the development of new technologies over the centuries. The pen, the printing press, the computer and the mobile phone are all technological developments which have altered what is written, and the medium through which the written word is produced. Particularly with the advent of digital technologies, namely the computer and the mobile phone, characters can be formed by the press of a button, rather than making a physical motion with the hand.

Writing materials

There is no very definite statement as to the material which was in most common use for the purposes of writing at the start of the early writing systems. In all ages it has been customary to engrave on stone or metal, or other durable material, with the view of securing the permanency of the record. Metals, such as stamped coins, are mentioned as a material of writing; they include lead, brass, and gold. There are also references to the engraving of gems, such as with seals or signets.

The common materials of writing were the tablet and the roll, the former probably having a Chaldean origin, the latter an Egyptian. The tablets of the Chaldeans are small pieces of clay, somewhat crudely shaped into a form resembling a pillow, and thickly inscribed with cuneiform characters. Similar use has been seen in hollow cylinders, or prisms of six or eight sides, formed of fine terracotta, sometimes glazed, on which the characters were traced with a small stylus, in some specimens so minutely as to require the aid of a magnifying-glass.

In Egypt the principal writing material was of quite a different sort. Wooden tablets are found pictured on the monuments; but the material which was in common use, even from very ancient times, was the papyrus, having recorded use as far back as 3,000 BCE. This reed, found chiefly in Lower Egypt, had various economic means for writing. The pith was taken out and divided by a pointed instrument into the thin pieces of which it is composed; it was then flattened by pressure, and the strips glued together, other strips being placed at right angles to them, so that a roll of any length might be manufactured. Writing seems to have become more widespread with the invention of papyrus in Egypt. That this material was in use in Egypt from a very early period is evidenced by still existing papyrus of the earliest Theban dynasties. As the papyrus, being in great demand, and exported to all parts of the world, became very costly, other materials were often used instead of it, among which is mentioned leather, a few leather mills of an early period having been found in the tombs. Parchment, using sheepskins left after the wool was removed for cloth, was sometimes cheaper than papyrus, which had to be imported outside Egypt. With the invention of wood-pulp paper, the cost of writing material began a steady decline. Wood-pulp paper is still used today, and in recent times efforts have been made in order to improve bond strength of fibers. Two main areas of examination in this regard have been "dry strength of paper" and "wet web strength". The former involves examination of the physical properties of the paper itself, while the latter involves using additives to improve strength.

Uses and implications of writing

Writing and the economy

According to Denise Schmandt-Besserat writing had its origins in the counting and cataloguing of agricultural produce, and then economic transactions involving the produce. Government tax rolls followed thereafter. Written documents became essential for the accumulation and accounting of wealth by individuals, the state, and religious organizations as well as the transactions of trade, loans, inheritance, and documentation of ownership. With such documentation and accounting larger accumulations of wealth became more possible, along with the power that accompanied wealth, most prominently to the benefit of royalty, the state, and religions. Contracts and loans supported the growth of long-distance international trade with accompanying networks for import and export, supporting the rise of capitalism. Paper money (initially appearing in China in the 11th century CE) and other financial instruments relied on writing, initially in the form of letters and then evolving into specialized genres, to explain the transactions and guarantees (from individuals, banks, or governments) of value inhering in the documents. With the growth of economic activity in late Medieval and Renaissance Europe, sophisticated methods of accounting and calculating value emerged, with such calculations both carried out in writing and explained in manuals. The creation of corporations then proliferated documents surrounding organization, management, the distribution of shares, and record-keeping.

Economic theory itself only began to be developed in the latter eighteenth century through the writings of such theorists as Francois Quesnay and Adam Smith. Even the concepts of an economy and a national economy were established through their texts and the texts of their colleagues. Since then economics has developed as a field with many authors contributing texts to the professional literature, and governments collecting data, instituting policies and creating institutions to manage and advance their economies. Diedre McCloskey has examined the rhetorical strategies and discursive construction of modern economic theory. Graham Smart has examined in depth how the Bank of Canada uses writing to cooperatively produce policies based on economic data and then to communicate strategically with relevant publics.

Writing and religion

The identification of sacred religious texts or scriptures, often claimed to be of divine origin, codified distinct belief systems associated with particular divine texts, and became the basis of the modern concept of religion. The reproduction and spread of these texts became associated with these scriptural religions and their spread, and thus were central to proselytizing. These sacred books created obligations of believers to read, or to follow the teachings of priests or priestly castes charged with the reading, interpretation and application of these texts. Well-known examples of such scriptures are the Torah, the Bible (with its many different compilations of books of the Old and New Testaments), the Quran, the Vedas, the Bhaghavad Gita, and the Sutras, but there are far more religious texts through the histories of different religions with many still in current use. These texts, because of their spread, tended to foster generalized guides for moral and ethical behavior, at least for all members of the religious community, but often these guidelines were considered applicable to all humans, as in the ten commandments.

Writing and the law

Private legal documents for the sale of land appeared in Mesopotamia in the early third millennium BCE, not long after the initial appearance of cuneiform writing. The first written legal codes followed shortly thereafter around 2100 BCE, with the most well known being the Code of Hammurabi, inscribed on stone stellae throughout Babylon circa 1750 BCE. While Ancient Egypt did not have codified laws, legal decrees and private contracts did appear in the Old Kingdom around 2150 BCE. The Torah, or the first five books of the Hebrew Bible, particularly Exodus and Deutoronomy, codified the laws of Ancient Israel. Many other codes were to follow in Greece and Rome, with Roman law to serve as a model for church canon law and secular law throughout much of Europe during later periods.

In China the earliest indications of written codifications of law or books of punishments are inscriptions on bronze vessels in 536 BCE. The earliest extant full set of laws dates back to the Qin and Han Dynasties, which set out a full system of social control and governance, with criminal procedures and accountability for both government officials and citizens. These laws required complex reporting and documenting procedures to facilitate hierarchical supervision from the village up to the imperial center.

While Common Law developed in a mostly oral environment in England after the Romans left, with the return of the church and then the Norman invasion, customary law began to be inscribed as were precedents of the courts; however, many elements remained oral, with documents only memorializing public oaths, wills, land transfers, court judgments, and ceremonies. During the late Medieval period, however, documents gained authority for agreements, transactions, and laws. With the founding of the United States laws were created as statutes within written codes and controlled by central documents, including the federal and state Constitutions, with all such legislative documents printed and distributed. Also court judgments were presented in written opinions which then were published and served as precedents for reasoning in consequent judgments in states and nationally. Courts of Appeals in the United States only consider documents relating to records of prior proceedings and judgements and do not take new testimony.

Writing and government, states, bureaucracy, citizenship, and journalism

Writing has been central to expanding many of the core functions of governance through law, regulation, taxation, and documentary surveillance of citizens; all dependent on growth of bureaucracy which elaborates and administers rules and policies and maintains records (see red tape). These developments which rely on writing increase the power and extent of states. At the same time writing has increased the ability of citizens to become informed about the operations of the state, to become more organized in expressing needs and concerns, to identify with regions and states, and to form constituencies with particular views and interests; the rise and fate of journalism is closely linked to citizen information, regional and national identity, and expression of interests. These changes have greatly influenced the nature of states, increasing the visibility of people and their views no matter what the form of governance is.

Extensive bureaucracies arose in the ancient Near East and China which relied on the formation of literate classes to be scribes and bureaucrats. In the Ancient Near East this was carried out through the formation of scribal schools, while in China this led to a series of written imperial examinations based on classic texts which in effect regulated education over millennia. Literacy remained associated with rise in the government bureaucracy, and printing as it emerged was tightly controlled by the government, with vernacular texts only emerging later and then being limited in their range up through the early twentieth century and the fall of the Ching dynasty. In ancient Greece and Rome, class distinctions of citizen and slave, wealthy and poor limited education and participation. In Medieval and early modern Europe church dominance of education, both before and for a time after the reformation, expressed the importance of religion in the control of the state and state bureaucracies.

In Europe and the colonies in the Americas the introduction of the printing press and decreasing cost of paper and printing allowed for greater access of ordinary citizens to gain information about the government and conditions in other regions within the jurisdictions. The Reformation with an emphasis on individual reading of sacred texts, eventually increased the spread of literacy beyond the governing classes and opened the door to wider knowledge and criticism of government actions. Divisions in English society during the sixteenth century, the Civil War of the seventeenth century, and the increased role of parliament that followed, along with the splitting of political religious control were accompanied by pamphlet wars.

Newspapers and journalism, having origins in commercial information, soon was to offer political information and was instrumental to the formation of a public sphere. Newspapers were instrumental in the sharing of information, fostering discussion, and forming political identities in the American revolution, and then the new nation. The circulation of newspapers also created urban, regional, and state identification in the latter nineteenth century and after. A focus on national news that followed telegraphy and the emergence of newspapers with national circulation along with scripted national radio and television news broadcasts also created horizons of attention through the twentieth century, with both benefits and costs.

One of the earliest known examples of a named person in writing is Kushim, from the Uruk period.

Writing and knowledge

Much of what we consider knowledge is inscribed in written text and is the result of communal processes of production, sharing, and evaluation among social groups and institutions bound together with the aim of producing and disseminating knowledge-bearing texts; the contemporary world identifies such social groups as disciplines and their products as disciplinary literatures. The invention of writing facilitated the sharing, comparing, criticizing, and evaluating of texts, resulting in knowledge becoming a more communal property across wider geographic and temporal domains. Sacred scriptures formed the common knowledge of scriptural religions, and knowledge of those sacred scriptures became the focus of institutions of religious belief, interpretation, and schooling, as discussed in the section on writing and religion in this article. Other sections in this article are devoted to knowledge specific to the economy, the law, and governance. This section is devoted to the development of secular knowledge and its related social organizations, institutions, and educational practices in other domains.

Mesopotamia, Egypt, India, and Mesoamerica

In Mesopotamia and Egypt, scribes became important for roles beyond the initiating roles in the economy, governance and law. They became the producers and stewards of astronomy and calendars, divination, and literary culture. Schools developed in tablet houses, which also archived repositories of knowledge. In ancient India, the Brahman caste became stewards of texts that aggregated and codified oral knowledge. Those texts then became the authoritative basis for a continuing tradition of oral education. A case in point is the work of Pāṇini the linguist, who analyzed and codified knowledge of Sanskrit syntax, prosody and grammar. Mathematics, astronomy and medicine were also subjects of classic Indian learning and were codified in classic texts. Less is known about Mayan, Aztec, and other Mesoamerican learning because of the destruction of texts by the conquistadors, but it is known that scribes were revered, elite children attended schools, and the study of astronomy, map making, historical chronicles, and genealogy flourished.

China

In China, after the Qin dynasty attempted to remove all traces of the competing Confucian tradition, the Han dynasty made philological knowledge the qualification for the government bureaucracy, so as to restore knowledge that was in danger of vanishing. The Imperial civil service examination system, which was to last for two millennia, consisted of a written exam based on knowledge of classical texts. To support students obtaining government positions through the written examination, schools focused on those same texts and the associated philological knowledge. These texts covered philosophical, religious, legal, astronomical, hydrological, mathematical, military, and medical knowledge. Printing as it emerged largely served the knowledge needs of the bureaucracy and the monastery, with substantial vernacular printing only emerging around the fifteenth century CE.

Ancient Greece and Rome

Ancient Greece gave rise to much written knowledge that influenced western learning for two millennia. Although Socrates thought writing an inferior means of transmission of learning (recounted in the Phaedrus), we know of his works through Plato's written accounts of his dialogues. Havelock, as well, has seen the philosophic works of Plato, Socrates, and Aristotle as arising from literacy and the ability to compare accounts from different regions and to develop systematic critical reasoning through the inspection of documents and writing coherent accounts. Aristotle wrote treatises and lectures which were the core of education at the Lyceum, along with the may volumes collected in the Lyceum's library. Other philosophers such as the Stoics and Epicureans also wrote and taught during the same period in Athens, although we now have only fragments of their works.

Greek writers were the founding writers of many other fields of knowledge. Herodotus and Thucydides writing during the fifth century BCE in Athens are considered the founders of history, transforming genealogy and mythic accounts into systematic investigations of events. Thucydides developed a more critical, neutral history through the examination of documents, transcription of speeches, and interviews. Hippocrates during the same period authored several major works of medicine codifying and advancing the knowledge of this field. In the second century CE the Greek trained physician Galen went to Rome where he wrote numerous works that dominated European medicine through the Renaissance. Hellenized writers in Egypt also produced compendia of knowledge using the resources of the great library at Alexandria, such as Euclid whose Elements of geometry remains a standard reference to today. Ptolemy's work on astronomy dominated through the Middle Ages.

Scholars in Rome continued the practice of writing compendia of knowledge, including Varro, Pliny the Elder, and Strabo. While much of Roman accomplishment was in material culture of construction, Vitruvius documented much of the contemporary practice to influence design until today. Agriculture also became an important area for manuals, such as Palladius' compendium. Numerous manuals of rhetoric and rhetorical education that were to influence future generations also appeared, such as the anonymous Rhetorica ad Herennium, Cicero's de Oratore and Quintilian's Institutio Oratoria.

Islamic learning

With the fall of Rome, the Middle East became the crossroads for learning, with knowledge bearing texts from the West and East meeting in Byzantium, Damascus, and then Baghdad. In Baghdad a research institute (or House of Wisdom) with a large library was founded, where Greek works of medicine, philosophy, mathematics and astronomy were translated into Arabic, along with Indian works on mathematics and therapeutics. To these texts, philosophers such as Al-Kindi and Avicenna and astronomers such as Al-Farqhani made new contributions. Al-Kharazami authored the first work on algebra, drawing on both Greek and Indian resources. The centrality of the Quran to the new Islamic religion also led to growth of Arabic Linguistics. From Baghdad knowledge and texts were to flow back to South Asia and down through Africa, with a large collection of books and an educational center around the Sankhore Mosque in Timbuktu, the seat of the Songhai Empire. During this period the deposed Abbasid Caliphate moved its seat of power and learning to Córdoba, now in Spain, where they founded a major library which reintroduced many of the classic texts back into Europe along with texts of Arab learning.

Early universities in Europe

The reintroduction of classic texts into Europe through the library and intercultural intellectual culture in Córdoba, including works of Plato, Aristotle, Euclid, Ptolemy and Galen, along with Arabic texts such as by Avicenna and Al-Kharazami created a need for interpretation, lectures, and scholarship to make those works more accessible to scholars in monasteries and urban centers. During the twelfth century universities emerged from these clusters of scholars in Italy at Bologna; in Spain at Salamanca, in France at Paris and in England at Oxford. By 1500 there were at least sixty universities throughout Europe enrolling at least three quarters of a million students. Each of the four faculties (Liberal Arts, Theology, Law, and Medicine) was devoted to the transmission of classic texts rather than the production of fresh knowledge beyond lectures and commentaries. This form of scholastic education continued well into the seventeenth century and beyond in some locations and disciplines.

Printing and the growth of knowledge in Europe

Johannes Gutenberg’s European introduction of the moveable type printing press around 1450 created new opportunities for the production and widespread distribution of books, fostering much new writing, with particular consequences for the development of knowledge, as documented by Elizabeth Eisenstein. The production and distribution of knowledge was no longer tied to monasteries or universities with their libraries and collections of scribal copies. In the ensuing centuries a politically and increasingly religiously divided Europe, no single authority was able to censor or control the production of books. While universities remained attached to disseminating traditional texts, publishing houses became the new centers of knowledge production, and publishing houses in different jurisdictions led to a diversity of ideas becoming available as books moved across borders and scholars came to see themselves as citizens of the Republic of Letters.

The comparison of multiple editions of traditional texts led to improved textual scholarship. The ability to share and compare results from many regions and enlist more people into the production of science soon led to the development of early modern science. Books of medicine began to incorporate observations from contemporary surgery and dissections, including printed plates providing graphic displays, to improve knowledge of anatomy. With many copies of traditional books and new books appearing, debates arose over the value of each in what became known as the battle of the books. Maps and discoveries of exploration and colonization also were recorded in books and governmental records, often with the purpose of economic exploitation as in the Archives of the Indies in Seville but also to satisfy curiosity about the world.

Printing also made possible the invention and development of scientific journals, with the Journal des sçavans appearing in France and The Philosophical Transactions of the Royal Society in England both in 1665. Over the years these journals proliferated and became the basis of disciplines and disciplinary literatures. Genres reporting experiments and other scientific observations and theories developed over the ensuing centuries to produce modern practices of disciplinary publication with the extensive intertexts which represent the collective pursuits of disciplinary knowledge. The availability of scientific and disciplinary books and journals also facilitated the development of modern practices of scientific reference and citation. These developments from the impact of printing on the growth of knowledge contributed to the scientific revolution, science in the Renaissance and science in the Age of Enlightenment.

Modern research university and writing

In the eighteenth century a few Scottish and English dissident universities began offering some more practical and contemporary studies offered instruction in rhetoric and writing to enable their non-elite students to influence contemporary events. Only in the nineteenth century, however, did universities in some countries begin creating place for the writing of new knowledge, turning them in the ensuing years from primarily disseminating classic knowledge through the reading of classic texts to becoming institutions devoted to both reading and writing. The creation of research seminars and the associated seminar papers in history and philology in German Universities were a significant starting point for the reform of the university.[128] Professorships in philology, history, economy, theology, psychology, sociology, mathematics and the sciences were to emerge over the century, and the German model of disciplinary research university was to influence the organization of universities in England and the United States, with another model developing in France. Both, however, prized the production of new knowledge by faculty and to be learned by students. In elite British universities writing instruction was supported by the tutorial system with weekly writing by students for their tutors, while in the United States regular courses in writing were often required starting in the late nineteenth century, with writing across the curriculum becoming an increasing focus, particularly towards the end of the twentieth century.

Military knowledge and classified documents

Military knowledge of strategies and devices date back to the ancient worlds of Egypt, India, China, Greece, and Rome, with both historical accounts and manuals for conducting war. After printing was introduced in the West, manuals for construction of fortifications and battle strategies were widely reproduced, as nations frequently were in conflict. With the growth of chemistry and other sciences, however, knowledge of new weaponry was frequently restricted to secret documents. Other documents also of limited distribution developed around policies, production, and distribution of the new weaponry. By World War I, both the Allied and Axis powers applied new technologies based on scientific advances to military uses, particularly chemical weapons, with over 5000 scientists engaged in developing and producing weaponry, while attempting to limit access to the information in secret documents. The drive towards secret knowledge, including novel research and not just applications of prior knowledge, became especially intense with the race to develop nuclear weapons in World War II as in the U.S. Manhattan Project. Aviation, rocketry, radar, encryption, and computing were also the subject of classified documents. This system of classification of knowledge continued after WWII ended as the Cold War ensued. The tension between the needs for military secrecy, open scientific research, and citizen deliberation over military policy led in the United States led to the Atomic Energy Act of 1946, which created civilian control, but through a continuing regime of classified knowledge.

Literature and writing

The history of literature followed after the development of writing in Sumer, which was initially used for accounting purposes. The very first writings from ancient Sumer by any reasonable definition do not constitute literature. The same is true of some of the early Egyptian hieroglyphics and the thousands of ancient Chinese government records. Scholars have disagreed concerning when written record-keeping became more like literature, but the oldest surviving literary texts date from a full millennium after the invention of writing. The earliest literary author known by name is Enheduanna, who is credited as the author of a number of works of Sumerian literature, including Exaltation of Inanna, in the Sumerian language during the 24th century BCE. The next earliest named author is Ptahhotep, who is credited with authoring The Maxims of Ptahhotep, an instructional book for young men in Egyptian composed in the 23rd century BCE. The Epic of Gilgamesh is an early notable poem, but it can also be seen as a political glorification of the historical King Gilgamesh of Sumer whose natural and supernatural accomplishments are recounted.

Psychological implications of writing

Walter Ong, Jack Goody, and Eric Havelock were among the earliest to systematically argue for the psychological and intellectual consequences of literacy. Ong argued that the introduction of writing changed the form of human consciousness from sensing the immediacy of the spoken word to the critical distance and systematization of words, which could be graphically displayed and ordered, such as in the works of Peter Ramus. Havelock attributed the emergence of Greek philosophic thought to the use of the written word which allowed the comparison of beliefs and belief systems and the critical examination of concepts. Jack Goody argued that written language fostered such practices as categorization, making lists, following formulas, developing recipes and prescriptions, and ultimately making and recording experiments. These practices changed the intellectual and psychological orientation of those who engaged with them.

While recognizing the possibilities of all these psychological and intellectual changes that accompanied these literate practices, Sylvia Scribner and Michael Cole argued that these changes did not come universally or automatically with literacy, but rather were dependent on the social uses made of literacy in their local contexts. They carried out field observation and experiments among the Vai people of West Africa, for whom the psychological impacts of literacy vary due to the three different contexts in which locals learn to read and write the Vai language, English, and Arabic--practical skills, secular education, and religious education, respectively. European language literacies were associated with European style schooling, and fostered among other things syllogistic reasoning and logical problem solving. Arabic literacy was associated with the religious training of Madrasas and fostered, among other things, heightened rote memory. Literacy in the written forms of Vai associated with daily practices of making requests and explaining tasks, increased anticipation of audience knowledge and needs along with rebus solving (as the written language used rebus-like icons).

Following a different line of Inquiry, James Pennebaker and colleagues have carried out many experiments establishing that writing about traumas can relieve anxiety, improve mental well-being, and improve physical health measures and outcomes.

Saturday, October 28, 2023

Astronomical unit

From Wikipedia, the free encyclopedia
https://en.wikipedia.org/wiki/Astronomical_unit
 
Astronomical unit
The grey line indicates the Earth–Sun distance, which on average is about 1 astronomical unit.
General information
Unit systemAstronomical system of units
(Accepted for use with the SI)
Unit oflength
Symbolau or AU or AU
Conversions
1 au or AU or AU in ...... is equal to ...
   metric (SI) units   1.495978707×1011 m
   imperial & US units   9.2956×107 mi
   astronomical units   4.8481×10−6 pc
   1.5813×10−5 ly
   215.03 R

The astronomical unit (symbol: au, or AU or AU) is a unit of length, roughly the distance from Earth to the Sun and approximately equal to 150 million kilometres (93 million miles) or 8.3 light-minutes. The actual distance from Earth to the Sun varies by about 3% as Earth orbits the Sun, from a maximum (aphelion) to a minimum (perihelion) and back again once each year. The astronomical unit was originally conceived as the average of Earth's aphelion and perihelion; however, since 2012 it has been defined as exactly 149597870700 m.

The astronomical unit is used primarily for measuring distances within the Solar System or around other stars. It is also a fundamental component in the definition of another unit of astronomical length, the parsec.

History of symbol usage

A variety of unit symbols and abbreviations have been in use for the astronomical unit. In a 1976 resolution, the International Astronomical Union (IAU) had used the symbol A to denote a length equal to the astronomical unit. In the astronomical literature, the symbol AU was (and remains) common. In 2006, the International Bureau of Weights and Measures (BIPM) had recommended ua as the symbol for the unit, from the French "unité astronomique". In the non-normative Annex C to ISO 80000-3:2006 (now withdrawn), the symbol of the astronomical unit was also ua.

In 2012, the IAU, noting "that various symbols are presently in use for the astronomical unit", recommended the use of the symbol "au". The scientific journals published by the American Astronomical Society and the Royal Astronomical Society subsequently adopted this symbol. In the 2014 revision and 2019 edition of the SI Brochure, the BIPM used the unit symbol "au". ISO 80000-3:2019, which replaces ISO 80000-3:2006, does not mention the astronomical unit.

Development of unit definition

Earth's orbit around the Sun is an ellipse. The semi-major axis of this elliptic orbit is defined to be half of the straight line segment that joins the perihelion and aphelion. The centre of the Sun lies on this straight line segment, but not at its midpoint. Because ellipses are well-understood shapes, measuring the points of its extremes defined the exact shape mathematically, and made possible calculations for the entire orbit as well as predictions based on observation. In addition, it mapped out exactly the largest straight-line distance that Earth traverses over the course of a year, defining times and places for observing the largest parallax (apparent shifts of position) in nearby stars. Knowing Earth's shift and a star's shift enabled the star's distance to be calculated. But all measurements are subject to some degree of error or uncertainty, and the uncertainties in the length of the astronomical unit only increased uncertainties in the stellar distances. Improvements in precision have always been a key to improving astronomical understanding. Throughout the twentieth century, measurements became increasingly precise and sophisticated, and ever more dependent on accurate observation of the effects described by Einstein's theory of relativity and upon the mathematical tools it used.

Improving measurements were continually checked and cross-checked by means of improved understanding of the laws of celestial mechanics, which govern the motions of objects in space. The expected positions and distances of objects at an established time are calculated (in au) from these laws, and assembled into a collection of data called an ephemeris. NASA's Jet Propulsion Laboratory HORIZONS System provides one of several ephemeris computation services.

In 1976, to establish an even precise measure for the astronomical unit, the IAU formally adopted a new definition. Although directly based on the then-best available observational measurements, the definition was recast in terms of the then-best mathematical derivations from celestial mechanics and planetary ephemerides. It stated that "the astronomical unit of length is that length (A) for which the Gaussian gravitational constant (k) takes the value 0.01720209895 when the units of measurement are the astronomical units of length, mass and time". Equivalently, by this definition, one au is "the radius of an unperturbed circular Newtonian orbit about the sun of a particle having infinitesimal mass, moving with an angular frequency of 0.01720209895 radians per day"; or alternatively that length for which the heliocentric gravitational constant (the product GM) is equal to (0.01720209895)2 au3/d2, when the length is used to describe the positions of objects in the Solar System.

Subsequent explorations of the Solar System by space probes made it possible to obtain precise measurements of the relative positions of the inner planets and other objects by means of radar and telemetry. As with all radar measurements, these rely on measuring the time taken for photons to be reflected from an object. Because all photons move at the speed of light in vacuum, a fundamental constant of the universe, the distance of an object from the probe is calculated as the product of the speed of light and the measured time. However, for precision the calculations require adjustment for things such as the motions of the probe and object while the photons are transiting. In addition, the measurement of the time itself must be translated to a standard scale that accounts for relativistic time dilation. Comparison of the ephemeris positions with time measurements expressed in Barycentric Dynamical Time (TDB) leads to a value for the speed of light in astronomical units per day (of 86400 s). By 2009, the IAU had updated its standard measures to reflect improvements, and calculated the speed of light at 173.1446326847(69) au/d (TDB).

In 1983, the CIPM modified the International System of Units (SI) to make the metre defined as the distance travelled in a vacuum by light in 1 / 299792458 second. This replaced the previous definition, valid between 1960 and 1983, which was that the metre equalled a certain number of wavelengths of a certain emission line of krypton-86. (The reason for the change was an improved method of measuring the speed of light.) The speed of light could then be expressed exactly as c0 = 299792458 m/s, a standard also adopted by the IERS numerical standards. From this definition and the 2009 IAU standard, the time for light to traverse an astronomical unit is found to be τA = 499.0047838061±0.00000001 s, which is slightly more than 8 minutes 19 seconds. By multiplication, the best IAU 2009 estimate was A = c0τA = 149597870700±3 m, based on a comparison of Jet Propulsion Laboratory and IAA–RAS ephemerides.

In 2006, the BIPM reported a value of the astronomical unit as 1.49597870691(6)×1011 m. In the 2014 revision of the SI Brochure, the BIPM recognised the IAU's 2012 redefinition of the astronomical unit as 149597870700 m.

This estimate was still derived from observation and measurements subject to error, and based on techniques that did not yet standardize all relativistic effects, and thus were not constant for all observers. In 2012, finding that the equalization of relativity alone would make the definition overly complex, the IAU simply used the 2009 estimate to redefine the astronomical unit as a conventional unit of length directly tied to the metre (exactly 149597870700 m). The new definition also recognizes as a consequence that the astronomical unit is now to play a role of reduced importance, limited in its use to that of a convenience in some applications.

1 astronomical unit  = 149597870700 metres (by definition)
= 149597870.7 kilometres (exactly)
92955807.2730 miles
499.004783836 light-seconds
1.58125074098×10−5 light-years
4.84813681113×10−6 parsecs

This definition makes the speed of light, defined as exactly 299792458 m/s, equal to exactly 299792458 × 86400 ÷ 149597870700 or about 173.144632674240 au/d, some 60 parts per trillion less than the 2009 estimate.

Usage and significance

With the definitions used before 2012, the astronomical unit was dependent on the heliocentric gravitational constant, that is the product of the gravitational constant, G, and the solar mass, M. Neither G nor M can be measured to high accuracy separately, but the value of their product is known very precisely from observing the relative positions of planets (Kepler's third law expressed in terms of Newtonian gravitation). Only the product is required to calculate planetary positions for an ephemeris, so ephemerides are calculated in astronomical units and not in SI units.

The calculation of ephemerides also requires a consideration of the effects of general relativity. In particular, time intervals measured on Earth's surface (Terrestrial Time, TT) are not constant when compared with the motions of the planets: the terrestrial second (TT) appears to be longer near January and shorter near July when compared with the "planetary second" (conventionally measured in TDB). This is because the distance between Earth and the Sun is not fixed (it varies between 0.9832898912 and 1.0167103335 au) and, when Earth is closer to the Sun (perihelion), the Sun's gravitational field is stronger and Earth is moving faster along its orbital path. As the metre is defined in terms of the second and the speed of light is constant for all observers, the terrestrial metre appears to change in length compared with the "planetary metre" on a periodic basis.

The metre is defined to be a unit of proper length. Indeed, the International Committee for Weights and Measures (CIPM) notes that "its definition applies only within a spatial extent sufficiently small that the effects of the non-uniformity of the gravitational field can be ignored". As such, a distance within the Solar System without specifying the frame of reference for the measurement is problematic. The 1976 definition of the astronomical unit was incomplete because it did not specify the frame of reference in which to apply the measurement, but proved practical for the calculation of ephemerides: a fuller definition that is consistent with general relativity was proposed, and "vigorous debate" ensued until August 2012 when the IAU adopted the current definition of 1 astronomical unit = 149597870700 metres.

The astronomical unit is typically used for stellar system scale distances, such as the size of a protostellar disk or the heliocentric distance of an asteroid, whereas other units are used for other distances in astronomy. The astronomical unit is too small to be convenient for interstellar distances, where the parsec and light-year are widely used. The parsec (parallax arcsecond) is defined in terms of the astronomical unit, being the distance of an object with a parallax of 1″. The light-year is often used in popular works, but is not an approved non-SI unit and is rarely used by professional astronomers.

When simulating a numerical model of the Solar System, the astronomical unit provides an appropriate scale that minimizes (overflow, underflow and truncation) errors in floating point calculations.

History

The book On the Sizes and Distances of the Sun and Moon, which is ascribed to Aristarchus, says the distance to the Sun is 18 to 20 times the distance to the Moon, whereas the true ratio is about 389.174. The latter estimate was based on the angle between the half-moon and the Sun, which he estimated as 87° (the true value being close to 89.853°). Depending on the distance that van Helden assumes Aristarchus used for the distance to the Moon, his calculated distance to the Sun would fall between 380 and 1,520 Earth radii.

According to Eusebius in the Praeparatio evangelica (Book XV, Chapter 53), Eratosthenes found the distance to the Sun to be "σταδιων μυριαδας τετρακοσιας και οκτωκισμυριας" (literally "of stadia myriads 400 and 80000) but with the additional note that in the Greek text the grammatical agreement is between myriads (not stadia) on the one hand and both 400 and 80000 on the other, as in Greek, unlike English, all three (or all four if one were to include stadia) words are inflected. This has been translated either as 4080000 stadia (1903 translation by Edwin Hamilton Gifford), or as 804000000 stadia (edition of Édourad des Places [de], dated 1974–1991). Using the Greek stadium of 185 to 190 metres, the former translation comes to 754800 km to 775200 km, which is far too low, whereas the second translation comes to 148.7 to 152.8 million kilometres (accurate within 2%). Hipparchus also gave an estimate of the distance of Earth from the Sun, quoted by Pappus as equal to 490 Earth radii. According to the conjectural reconstructions of Noel Swerdlow and G. J. Toomer, this was derived from his assumption of a "least perceptible" solar parallax of 7.

A Chinese mathematical treatise, the Zhoubi Suanjing (c. 1st century BCE), shows how the distance to the Sun can be computed geometrically, using the different lengths of the noontime shadows observed at three places 1,000 li apart and the assumption that Earth is flat.

Distance to the Sun
estimated by
Estimate In au
Solar
parallax
Earth
radii
Aristarchus (3rd century BCE)
(in On Sizes)  
13′ 24″7′ 12″ 256.5477.8 0.0110.020
Archimedes (3rd century BCE)
(in The Sand Reckoner)
21″ 10000 0.426
Hipparchus (2nd century BCE) 7′ 490 0.021
Posidonius (1st century BCE)
(quoted by coeval Cleomedes)
21″ 10000 0.426
Ptolemy (2nd century) 2′ 50″ 1,210 0.052
Godefroy Wendelin (1635) 15″ 14000 0.597
Jeremiah Horrocks (1639) 15″ 14000 0.597
Christiaan Huygens (1659) 8.2″ 25086 1.068
Cassini & Richer (1672) 9.5″ 21700 0.925
Flamsteed (1672) 9.5″ 21700 0.925
Jérôme Lalande (1771) 8.6″ 24000 1.023
Simon Newcomb (1895) 8.80″ 23440 0.9994
Arthur Hinks (1909) 8.807″ 23420 0.9985
H. Spencer Jones (1941) 8.790″ 23466 1.0005
modern astronomy 8.794143 23455 1.0000

In the 2nd century CE, Ptolemy estimated the mean distance of the Sun as 1,210 times Earth's radius. To determine this value, Ptolemy started by measuring the Moon's parallax, finding what amounted to a horizontal lunar parallax of 1° 26′, which was much too large. He then derived a maximum lunar distance of 64+1/6 Earth radii. Because of cancelling errors in his parallax figure, his theory of the Moon's orbit, and other factors, this figure was approximately correct. He then measured the apparent sizes of the Sun and the Moon and concluded that the apparent diameter of the Sun was equal to the apparent diameter of the Moon at the Moon's greatest distance, and from records of lunar eclipses, he estimated this apparent diameter, as well as the apparent diameter of the shadow cone of Earth traversed by the Moon during a lunar eclipse. Given these data, the distance of the Sun from Earth can be trigonometrically computed to be 1,210 Earth radii. This gives a ratio of solar to lunar distance of approximately 19, matching Aristarchus's figure. Although Ptolemy's procedure is theoretically workable, it is very sensitive to small changes in the data, so much so that changing a measurement by a few per cent can make the solar distance infinite.

After Greek astronomy was transmitted to the medieval Islamic world, astronomers made some changes to Ptolemy's cosmological model, but did not greatly change his estimate of the Earth–Sun distance. For example, in his introduction to Ptolemaic astronomy, al-Farghānī gave a mean solar distance of 1,170 Earth radii, whereas in his zij, al-Battānī used a mean solar distance of 1,108 Earth radii. Subsequent astronomers, such as al-Bīrūnī, used similar values. Later in Europe, Copernicus and Tycho Brahe also used comparable figures (1,142 and 1,150 Earth radii), and so Ptolemy's approximate Earth–Sun distance survived through the 16th century.

Johannes Kepler was the first to realize that Ptolemy's estimate must be significantly too low (according to Kepler, at least by a factor of three) in his Rudolphine Tables (1627). Kepler's laws of planetary motion allowed astronomers to calculate the relative distances of the planets from the Sun, and rekindled interest in measuring the absolute value for Earth (which could then be applied to the other planets). The invention of the telescope allowed far more accurate measurements of angles than is possible with the naked eye. Flemish astronomer Godefroy Wendelin repeated Aristarchus’ measurements in 1635, and found that Ptolemy's value was too low by a factor of at least eleven.

A somewhat more accurate estimate can be obtained by observing the transit of Venus. By measuring the transit in two different locations, one can accurately calculate the parallax of Venus and from the relative distance of Earth and Venus from the Sun, the solar parallax α (which cannot be measured directly due to the brightness of the Sun). Jeremiah Horrocks had attempted to produce an estimate based on his observation of the 1639 transit (published in 1662), giving a solar parallax of 15, similar to Wendelin's figure. The solar parallax is related to the Earth–Sun distance as measured in Earth radii by

The smaller the solar parallax, the greater the distance between the Sun and Earth: a solar parallax of 15″ is equivalent to an Earth–Sun distance of 13750 Earth radii.

Christiaan Huygens believed that the distance was even greater: by comparing the apparent sizes of Venus and Mars, he estimated a value of about 24000 Earth radii, equivalent to a solar parallax of 8.6″. Although Huygens' estimate is remarkably close to modern values, it is often discounted by historians of astronomy because of the many unproven (and incorrect) assumptions he had to make for his method to work; the accuracy of his value seems to be based more on luck than good measurement, with his various errors cancelling each other out.

Transits of Venus across the face of the Sun were, for a long time, the best method of measuring the astronomical unit, despite the difficulties (here, the so-called "black drop effect") and the rarity of observations.

Jean Richer and Giovanni Domenico Cassini measured the parallax of Mars between Paris and Cayenne in French Guiana when Mars was at its closest to Earth in 1672. They arrived at a figure for the solar parallax of 9.5″, equivalent to an Earth–Sun distance of about 22000 Earth radii. They were also the first astronomers to have access to an accurate and reliable value for the radius of Earth, which had been measured by their colleague Jean Picard in 1669 as 3269000 toises. This same year saw another estimate for the astronomical unit by John Flamsteed, which accomplished it alone by measuring the martian diurnal parallax. Another colleague, Ole Rømer, discovered the finite speed of light in 1676: the speed was so great that it was usually quoted as the time required for light to travel from the Sun to the Earth, or "light time per unit distance", a convention that is still followed by astronomers today.

A better method for observing Venus transits was devised by James Gregory and published in his Optica Promata (1663). It was strongly advocated by Edmond Halley and was applied to the transits of Venus observed in 1761 and 1769, and then again in 1874 and 1882. Transits of Venus occur in pairs, but less than one pair every century, and observing the transits in 1761 and 1769 was an unprecedented international scientific operation including observations by James Cook and Charles Green from Tahiti. Despite the Seven Years' War, dozens of astronomers were dispatched to observing points around the world at great expense and personal danger: several of them died in the endeavour. The various results were collated by Jérôme Lalande to give a figure for the solar parallax of 8.6″. Karl Rudolph Powalky had made an estimate of 8.83″ in 1864.

Date Method A/Gm Uncertainty
1895 aberration 149.25 0.12
1941 parallax 149.674 0.016
1964 radar 149.5981 0.001
1976 telemetry 149.597870 0.000001
2009 telemetry 149.597870700 0.000000003

Another method involved determining the constant of aberration. Simon Newcomb gave great weight to this method when deriving his widely accepted value of 8.80″ for the solar parallax (close to the modern value of 8.794143), although Newcomb also used data from the transits of Venus. Newcomb also collaborated with A. A. Michelson to measure the speed of light with Earth-based equipment; combined with the constant of aberration (which is related to the light time per unit distance), this gave the first direct measurement of the Earth–Sun distance in kilometres. Newcomb's value for the solar parallax (and for the constant of aberration and the Gaussian gravitational constant) were incorporated into the first international system of astronomical constants in 1896, which remained in place for the calculation of ephemerides until 1964. The name "astronomical unit" appears first to have been used in 1903.

The discovery of the near-Earth asteroid 433 Eros and its passage near Earth in 1900–1901 allowed a considerable improvement in parallax measurement. Another international project to measure the parallax of 433 Eros was undertaken in 1930–1931.

Direct radar measurements of the distances to Venus and Mars became available in the early 1960s. Along with improved measurements of the speed of light, these showed that Newcomb's values for the solar parallax and the constant of aberration were inconsistent with one another.

Developments

The astronomical unit is used as the baseline of the triangle to measure stellar parallaxes (distances in the image are not to scale)

The unit distance A (the value of the astronomical unit in metres) can be expressed in terms of other astronomical constants:

where G is the Newtonian constant of gravitation, M is the solar mass, k is the numerical value of Gaussian gravitational constant and D is the time period of one day. The Sun is constantly losing mass by radiating away energy, so the orbits of the planets are steadily expanding outward from the Sun. This has led to calls to abandon the astronomical unit as a unit of measurement.

As the speed of light has an exact defined value in SI units and the Gaussian gravitational constant k is fixed in the astronomical system of units, measuring the light time per unit distance is exactly equivalent to measuring the product G×M in SI units. Hence, it is possible to construct ephemerides entirely in SI units, which is increasingly becoming the norm.

A 2004 analysis of radiometric measurements in the inner Solar System suggested that the secular increase in the unit distance was much larger than can be accounted for by solar radiation, +15±4 metres per century.

The measurements of the secular variations of the astronomical unit are not confirmed by other authors and are quite controversial. Furthermore, since 2010, the astronomical unit has not been estimated by the planetary ephemerides.

Environmental crime

From Wikipedia, the free encyclopedia

Environmental crime is an illegal act which directly harms the environment. These illegal activities involve the environment, wildlife, biodiversity and natural resources. International bodies such as, G7, Interpol, European Union, United Nations Environment Programme, United Nations Interregional Crime and Justice Research Institute, have recognised the following environmental crimes:

Environmental crime makes up almost a third of crimes committed by organizations such as; corporations, partnerships, unions, trusts, pension funds, and non-profits. It is the fourth largest criminal activity in the world and it is increasing by five to seven percent every year. These crimes are liable for prosecution. Interpol facilitates international police cooperation and assists its member countries in the effective enforcement of national and international environmental laws and treaties. Interpol began fighting environmental crime in 1992.

Costs

International criminal gangs and militant groups profit from the plunder of natural resources and these illegal profits are soaring. Terrorism and even civil wars are consequences of environmental crime. According to UNEP and Interpol, in June 2016 the value of environmental crime is 26 per cent larger than previous estimates, at US$91–258 billion, compared to US$70–213 billion in 2014, outstripping illegal trade in small arms. More than half of this amount can be attributed to illegal logging and deforestation.

Prosecution by ICC

In September 2016 it was announced that the International Criminal Court (ICC) located in The Hague will prosecute government and individuals for environmental crimes. According to the Case Selection Criteria announced in Policy Paper on Case Selection and Prioritisation by ICC on 15 September 2016, the Office will give particular consideration to prosecuting Rome Statute crimes that are committed by means of, or that result in, "inter alia, the destruction of the environment, the illegal exploitation of natural resources or the illegal dispossession of land".

Environmental crime in the European Union

Within the European Union, the road to an effective enforcement of Environmental Crime legislation has been anything but straightforward. A major role is played by the Environmental Crime Directive, a 2008 instrument aimed at protecting the environment through the use of criminal law. Even though some studies show that there has been a decline in non-compliance with environmental policy by Member States, after over a decade from the publication of the first Directive, as part of the European Green Deal,the European Commission submitted a proposal for a new Directive with the aim of strengthening the enforcement and prosecution of environmental crimes through the use of clearer definitions and sanctions other than the typical fines and imprisonment.

Environmental crime by country

United States

Abandoned or little used areas are common dumping places in America -especially railroads. Over $10 million a year are used to remove illegal dumping from polluting towns and the environment. A small organization, CSXT Police Environment Crimes Unit, has been started to stop railroad dumping specifically.

Ever since the Environmental Protection Agency's Office of Criminal Enforcement was founded in 1982, there has been a steady increase in prosecuted environmental crimes. This includes the prosecution of companies that have illegally dumped or caused oil spills. On a federal level, while the EPA oversees the investigations, the prosecutions are typically brought by the U.S. Department of Justice, through its Environmental Crimes Section, and/or through one of the 94 U.S. Attorney's Office across the country.

In a 2004 case study, a 30-pound cylinder of CFC-12 could be purchased in China for US$40 and illegally sold in the US for US$600.

In 2000, California real estate developer Eric Diesel was sentenced to 6 months in jail and ordered to pay a $300,000 fine for grading an illegal road in the Santa Cruz Mountains.

Italy

An example of Ecomafia was Naples waste management where there was illegal dumping in the 1980s.

Nigeria

In Nigeria, the establishment of environmental agencies began in 1988 after an incident of dumping of toxic materials in the country by international waste traders (the infamous Koko incident). Presently, agencies such as the National Environmental Standards and Regulations Enforcement Agency (Nigeria) are empowered by Nigerian law to regulate the environment sector. This agency works with other organs of the government such as customs, police, military intelligence, etc., and has successfully seized illegally trafficked wildlife products and prosecuted a number persons, including non-nationals.

Singapore

As a trading hub, Singapore is susceptible to unnoticed contraband. Charles W. Schmidt explains how China sells illegal CFC-12 to the United States through Singapore due to the lack of inspections and confidentiality of private businesses in Singapore.

Russia

Violations of Russia's environmental protection laws cost the country more than $187 million in 2018. Out of nearly 23.9 thousand environmental crimes registered in Russia in 2018, the overwhelming majority were related to; the illegal cutting of forest plantations, amounting approximately to 13.8 thousand cases, and Illegal hunting, with over 1.9 thousand cases observed.

Enforcement

The effective enforcement of environmental laws is vital to any protection regimes that are designed to protect the environment. In the early days of environmental legislation, violations carried largely insignificant civil fines and penalties. Initial environmental laws and regulations had little or no deterrent effect on corporations, individuals, or governments to comply with environmental laws. Indeed, a major source of failure of US environmental protection legislation was the civil character of federal enforcement actions. Their chief sanction was fines, which many corporations took in stride as a cost of doing business. Environmental criminal law covers a narrower ground. Its core consists of the criminal provisions of eight federal statutes passed mainly in the 1970s and amended in the last two decades.

In many cases, particularly corporations found it more cost-effective to continue to pollute more than the law allowed and simply pay any associate fines if indeed the corporation was actually found and convicted of violating environmental laws or regulations. Kevin Tomkins believes corporations had a disincentive to comply with environmental laws or regulations as compliance generally raised their operational costs. This was interpreted as many corporations obeying the environmental laws, whether out of a sense of legal duty or public obligation, were disadvantaged and lost a competitive edge and consequently suffered in the marketplace to competitors who disregarded environmental laws and regulations. As a result of weak environmental legislation and continued adverse public opinion regarding the management of the environment, many governments established various environmental enforcement regimes that dramatically increased the legal powers of environmental investigators. The inclusion of criminal sanctions, significant increases in fines coupled with possible imprisonment of corporate officers changed the face of environmental law enforcement. For example, between 1983 and 1990 the US Department of Justice secured $57,358,404.00 in criminal penalties and obtained sentences of imprisonment for 55% of defendants charged with environmental offences.

Many environmental agencies like the Alabama Department of Conservation and National Resources # Peace Officers, Alabama Wildlife and Freshwater Fisheries Division, State Park Peace Officers and Alaska Game and Fish, Alaska State Troopers, Arizona Game and Fish play important roles in reducing environmental damage and protecting the environment through environmental laws and regulations. These agencies operate at varying levels from international, regional, national, state to local level keeping one agency working at one level. Various enforcement methods are employed by these agencies to warrant compliance with environmental laws and regulations. In some case's enforcement agencies use what is called "Command and Control" which are traditional regulatory approaches. In other cases, they may use economic incentive and hybrid-based approaches, which there are two. Moreover, it has increased the need for cooperation between different policing institutions. Environmental law enforcement agencies and police services do not operate in a vacuum; the legislative instruments that political systems implement govern their activities and responsibilities within society. However, ostensibly it is the legislative instruments implemented by governments that determine many of the strategies utilised by police services in protecting the environment. Generally these International, Regional, National and State legislative instruments are designed to ensure industries, individuals, and governments comply with the various environmental obligations embedded in national statutes and laws. There are also international legal instruments and treaties that also affect the way that sovereign states deal with environmental issues .

Environmental criminology

Environmental criminology examines the notions of crimes, offences and injurious behaviours against the environment and starts to examine the role that societies including corporations, governments and communities play in generating environmental harms. Criminology is now starting to recognise the impact of humans on the environment and how law enforcement agencies and the judiciary measure harm to the environment and attribute sanctions to the offenders. Environmental crime does not only affect the land, water, air, it affects the health of children as well. According to an article published in Environmental Health Perspectives in 2016, "The evolution and expansion of children's environmental health protection over the past two decades has been remarkable. At the U.S. EPA, significant efforts have been made to address the special susceptibility of children, and our work continues to address emerging environmental concerns to ensure that children's environments are free of hazards and support healthy development.

Lie point symmetry

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Lie_point_symmetry     ...