An Astrological Reversion Through Wikipedia

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Astrological Reversion


Globular A globular cluster is a spherical collection of stars that orbits a galactic core as a satellite. Globular clusters are very tightly bound by gravity, which gives them their spherical shapes and relatively high stellar densities toward their centers. The name of this category of star cluster is derived from the Latin globulus–a small sphere. A globular cluster is sometimes known more simply as a globular. Globular clusters are found in the halo of a galaxy and contain considerably more stars and are much older than the less dense open clusters, which are found in the disk of a galaxy. Globular clusters are fairly common; there are about 15 to 1 currently known globular clusters in the Milky Way, with perhaps 10 to 20 more still undiscovered. Larger galaxies can have more: Andromeda Galaxy, for instance, may have as many as 500. Some giant elliptical galaxies (particularly those at the centers of galaxy clusters), such as M, have as many as 13,000 globular clusters.

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Every galaxy of sufficient mass in the Local Group has an associated group of globular clusters, and almost every large galaxy surveyed has been found to possess a system of globular clusters. The Sagittarius Dwarf galaxy and the disputed Canis Major Dwarf galaxy appear to be in the process of donating their associated globular clusters (such as Palomar 12) to the Milky Way. This demonstrates how many of this galaxy’s globular clusters might have been acquired in the past. Although it appears that globular clusters contain some of the first stars to be produced in the galaxy, their origins and their role in galactic evolution are still unclear. It does appear clear that globular clusters are significantly different from dwarf elliptical galaxies and were formed as part of the star formation of the parent galaxy rather than as a separate galaxy.


Cluster The first known globular cluster, now called M22, was discovered in 1665 by Abraham Ihle, a German amateur astronomer. However, given the small aperture of early telescopes, individual stars within a globular cluster were not resolved until Charles Messier observed M4 in 1764. The first eight globular clusters discovered are shown in the table. Subsequently, Abbé Lacaille would list NGC 104, NGC 4833, M55, M69, and NGC 6397 in his 1751–52 catalogue. The M before a number refers to Charles Messier’s catalogue, while NGC is from the New General Catalogue by John Dreyer. When William Herschel began his comprehensive survey of the sky using large telescopes in 1782 there were 34 known globular clusters. Herschel discovered another 3 himself and was the first to resolve virtually all of them into stars. He coined the term “globular cluster” in his Catalogue of a Second Thousand New Nebulae and Clusters of Starspublished in 1789. The number of globular clusters discovered continued to increase, reaching 3 in 1915, 93 in 1930 and 97 by 1947. A total of 152 globular clusters have now been discovered in the Milky Way galaxy, out of an estimated total of 180 ± 20. These additional, undiscovered globular clusters are believed to be hidden behind the gas and dust of the Milky Way. Beginning in 1914, Harlow Shapley began a series of studies of globular clusters, published in about 40 scientific papers. He examined the RR Lyrae variables in the clusters (which he assumed were Cepheid variables) and used their period–luminosity relationship for distance estimates. Later, it was found that RR Lyrae variables are fainter than Cepheid variables, which caused Shapley to overestimate the distances of the clusters.

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Animism Animism (from Latin anima, “breath, spirit, life”) is the religious belief that objects, places and creatures all possess a distinct spiritual essence. Potentially, animism perceives all things–animals, plants, rocks, rivers, weather systems, human handiwork and perhaps even words–as animated and alive. Animism is the world’s oldest religion, “Animism predates any form of organized religion and is said to contain the oldest spiritual and supernatural perspective in the world. It dates back to the Paleolithic Age, to a time when humans roamed the plains hunting and gathering, and communing with the Spirit of Nature.”

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Animism is used in the anthropology of religion as a term for the belief system of many indigenous peoples, especially in contrast to the relatively more recent development of organised religions. Although each culture has its own different mythologies and rituals, “animism” is said to describe the most common, foundational thread of indigenous peoples’ “spiritual” or “supernatural” perspectives. The animistic perspective is so widely held and inherent to most indigenous peoples that they often do not even have a word in their languages that corresponds to “animism” (or even “religion”); the term is an anthropological construct. Largely due to such ethnolinguistic and cultural discrepancies, opinion has differed on whether animism refers to an ancestral mode of experience common to indigenous peoples around the world, or to a full-fledged religion in its own right. The currently accepted definition of animism was only developed in the late 19th century (1871) by Sir Edward Tylor, who created it as “one of anthropology’s earliest concepts, if not the first”. Animism encompasses the beliefs that all material phenomena have agency, that there exists no hard and fast distinction between the spiritual and physical (or material) world and that soul or spirit or sentience exists not only in humans, but also in other animals, plants, rocks, geographic features such as mountains or rivers or other entities of the natural environment, including thunder, wind and shadows. Animism thus rejects Cartesian dualism. Animism may further attribute souls to abstract concepts such as words, true names or metaphors in mythology. Some members of the non-tribal world also consider themselves animists (such as author Daniel Quinn, sculptor Lawson Oyekan and many contemporary Pagans).


A pow wow (also powwow or pow-wow) is a social gathering held by many different Native American communities. A modern pow wow is a specific type of event for Native American people to meet and dance, sing, socialize, and honor their cultures. Pow wows may be private or public. There is generally a dancing competition, with many different types of traditional dances, music and regalia, often with significant prize money awarded. Pow wows vary in length from a one-day event, to major pow wows called for a special occasion which can be up to one week long. In popular culture, such as older Western movies, the term has also been used to describe any gathering of Native Americans, or to refer to any type of meeting, such as among military personnel. (Some consider this use as offensive and disrespectful.)

The word “pow wow” is derived from the Narragansett word powwaw, meaning “spiritual leader”. The term itself has different variants including Powaw, Pawaw, Powah and Pawau. A number of different tribes claim to have held the “first” pow wow. Initially, public dances that most resemble what we now know as pow wows were most common in the Great Plains region of the United tates during the late nineteenth and early twentieth centuries, a time when the United States government fragmented many Native communities in the hopes of acquiring land for economic exploitation. In 1923, Charles Burke, Commissioner of Indian ffairs in the United States, passed legislation modeled on Circular 1665, which he published in 1921, that limited the times of the year in which Native Americans could practice traditional dance, which he deemed as directly threatening the Christian religion. However, many Native communities continued to gather together in secret to practice their cultures’ dance and music, in defiance of this, and other, legislation. By the mid-nineteenth century, pow wows were also being held in the Great Lakes region.

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PRO A protist is any eukaryotic organism (one with cells containing a nucleus) that is not an animal, plant or fungus. The protists do not form a natural group, or clade, since they exclude certain eukaryotes; but, like algae or invertebrates, they are often grouped together for convenience. In some systems of biological classification, such as the popular five-kingdom scheme proposed by Robert Whittaker in 1969, the protists make up a kingdom called Protista, composed of “organisms which are unicellular or unicellular-colonial and which form no tissues”. Besides their relatively simple levels of organization, protists do not necessarily have much in common. When used, the term “protists” is now considered to mean a paraphyletic assemblage of similar-appearing but diverse taxa (biological groups); these taxa do not have an exclusive common ancestor beyond being composed of eukaryotes and have different life cycles, trophic levels, modes of locomotion and cellular structures. In the classification system of Lynn Margulis, the term protist is reserved for microscopic organisms, while the more inclusive term Protoctista is applied to a biological kingdom that includes certain large multicellular eukaryotes, such as kelp, red algae and slime molds. Others use the term protist more broadly, to encompass both microbial eukaryotes and macroscopic organisms that do not fit into the other traditional kingdoms. In cladistic systems (classifications based on common ancestry), there are no equivalents to the taxa Protista or Protoctista, both terms referring to a paraphyletic group that spans the entire eukaryotic tree of life. In cladistic classification, the contents of Protista are distributed among various supergroups (SAR, such as protozoa and some algae, Archaeplastida, such as land plants and some algae, Excavata, which are a group of unicellular organisms, and Opisthokonta, such as animals and fungi, etc.). “Protista”, ‘’Protoctista’’ and “Protozoa” are considered obsolete. However, the term “protist” continues to be used informally as a catch-all term for unicellular eukaryotic microorganisms. For example, the word “protist pathogen” may be used to denote any disease-causing microbe that is not bacteria, virus, viroid or metazoa.

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TIST The term protista was first used by Ernst Haeckel in 1866. Protists were traditionally subdivided into several groups based on similarities to the "higher" kingdoms such as: Protozoa These unicellular "animal-like" (heterotrophic, and sometimes parasitic) organisms are further sub-divided based on characteristics such as motility, such as the (flagellated) Flagellata, the (ciliated) Ciliophora, the (phagocytic) amoeba, and the (spore-forming) Sporozoa. Protophyta These "plant-like" (autotrophic) organisms are composed mostly of unicellular algae. Molds Slime molds and water molds are "fungus-like" (saprophytic) organisms. Some protists, sometimes called ambiregnal protists, have been considered to be both protozoa and algae or fungi (e.g., slime molds and flagellated algae), and names for these have been published under either or both of the ICN and the ICZN. Conflicts, such as these–for example the dual-classification of Euglenids and Dinobryons, which are mixotrophic–is an example of why the kingdom Protista was adopted. These traditional subdivisions, largely based on superficial commonalities, have been replaced by classificationsbased on phylogenetics (evolutionary relatedness among organisms). Molecular analyses in modern taxonomyhave been used to redistribute former members of this group into diverse and sometimes distantly related phyla. For instance, the water molds are now considered to be closely related to photosynthetic organisms such as Brown algae and Diatoms, the slime molds are grouped mainly under Amoebozoa, and the Amoebozoa itself includes only a subset of "Amoeba" group, and significant number of erstwhile "Amoeboid" genera are distributed among Rhizarians and other Phyla. However, the older terms are still used as informal names to describe the morphology and ecology of various protists. For example, the term protozoa is used to refer to heterotrophic species of protists that do not form filaments.

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The tapetum lucidum (Latin: “bright tapestry; coverlet�, plural tapeta lucida) is a layer of tissue in the eye of many vertebrates. Lying immediately behind the retina, it is a retroreflector. It reflects visible lightback through the retina, increasing the light available to the photoreceptors(although slightly blurring the image). The tapetum lucidum contributes to the superior night vision of some animals. Many of these animals are nocturnal, especially carnivores, while others are deep sea animals. Similar adaptations occur in some species of spiders. Most primates, including humans, lack a tapetum lucidum, and compensate for this using perceptive recognition methods. Presence of a tapetum lucidum enables animals to see in dimmer light than would otherwise be possible. The tapetum lucidum, which is iridescent, reflects light roughly on the interference principles of thin-film optics, as seen in other iridescent tissues. However, the tapetum lucidum cells are leucophores, not iridophores.

The tapetum lucidum functions as a retroreflector which reflects light directly back along the light path. This serves to match the original and reflected light, thus maintaining the sharpness and contrast of the image on the retina. The tapetum lucidum reflects with constructive interference, thus increasing the quantity of light passing through the retina. In the cat, the tapetum lucidum increases the sensitivity of vision by 44%, allowing the cat to see light that is imperceptible to human eyes. It has been speculated that some flashlight fish may use eyeshine both to detect and to communicate with other flashlight fish.

Tapetum

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Dimensionless

Quantity In dimensional analysis, a dimensionless quantity is a quantity to which no physical dimension is assigned. It is also known as a bare number or pure number or a quantity of dimension one and the corresponding unit of measurement in the SI is one (or 1) unit and it is not explicitly shown. Dimensionless quantities are widely used in many fields, such as mathematics, physics, chemistry, engineering, and economics. Examples of quantities to which dimensions are regularly assigned are length, time, and speed, which are measured in dimensional units, such as metre, second and metre per second. This is considered to aid intuitive understanding. However, especially in mathematical physics, it is often more convenient to drop the assignment of explicit dimensions and express the quantities without dimensions, e.g., addressing the speed of light simply by the dimensionless number 1. Quantities having dimension 1, dimensionless quantities, regularly occur in sciences, and are formally treated within the field of dimensional analysis. In the nineteenth century, French mathematician Joseph Fourier and Scottish physicist James Clerk Maxwell led significant developments in the modern concepts of dimension and unit. Later work by British physicists Osborne Reynolds and Lord Rayleigh contributed to the understanding of dimensionless numbers in physics. Building on Rayleigh’s method of dimensional analysis, Edgar Buckingham proved the πtheorem (independent of French mathematician Joseph Bertrand’s previous work) to formalize the nature of these quantities.

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Numerous dimensionless numbers, mostly ratios, were coined in the early 1900s, particularly in the areas of fluid mechanics and heat transfer. Measuring ratios in the (derived) unit dB (decibel) finds widespread use nowadays. In the early 2000s, the International Committee for Weights and Measures discussed naming the unit of 1 as the “uno”, but the idea of just introducing a new SI-name for 1 was dropped.


Radio Radio galaxies and their relatives, radio-loud quasars and blazars, are types of active galaxy nuclei that are very luminous at radio wavelengths, with luminosities up to 1039 W between 10 MHz and 100 GHz. The radio emission is due to the synchrotron process. The observed structure in radio emission is determined by the interaction between twin jets and the external medium, modified by the effects of relativistic beaming. The host galaxies are almost exclusively large elliptical galaxies. Radio-loud active galaxies can be detected at large distances, making them valuable tools for observational cosmology. Recently, much work has been done on the effects of these objects on the intergalactic medium, particularly in galaxy groups and clusters.

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Emission processes The radio emission from radio-loud active galaxies is synchrotron emission, as inferred from its very smooth, broad-band nature and strong polarization. This implies that the radio-emitting plasma contains, at least, electrons with relativistic speeds (Lorentz factors of ~104) and magnetic fields. Since the plasma must be neutral, it must also contain either protons or positrons. There is no way of determining the particle content directly from observations of synchrotron radiation. Moreover, there is no way to determine the energy densities in particles and magnetic fields


Galaxies from observation: the same synchrotron emissivity may be a result of a few electrons and a strong field, or a weak field and many electrons, or something in between. It is possible to determine a minimum energy condition which is the minimum energy density that a region with a given emissivity can have, but for many years there was no particular reason to believe that the true energies were anywhere near the minimum energies. A sister process to the synchrotron radiation is the inverseCompton process, in which the relativistic electrons interact with ambient photons and Thomson scatter them to high energies. Inverse-Compton emission from radio-loud sources turns out to be particularly important in X-rays, and, because it depends only on the density of electrons, a detection of inverse-Compton scattering allows a somewhat model-dependent estimate of the energy densities in the particles and magnetic fields. This has been used to argue that many powerful sources are actually quite near the minimum-energy condition. Synchrotron radiation is not confined to radio wavelengths: if the radio source can accelerate particles to high enough energies, features that are detected in the radio wavelengths may also be seen in the infrared, optical, ultraviolet or even X-ray. In the latter case the responsible electrons must have energies in excess of 1 TeV in typical magnetic field strengths. Again, polarization and continuum spectrum are used to distinguish the synchrotron radiation from other emission processes. Jets and hotspots are the usual sources of high-frequency synchrotron emission. It is hard to distinguish observationally between the synchrotron and inverse-Compton radiation, making them a subject of ongoing research.

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Astrological Reversion


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