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 The Rebel Fleet, Laniakea Supercluster et Gabriela Mistral.

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yanis la chouette



Nombre de messages : 6759
Localisation : http://yanis.tignard.free.fr
Date d'inscription : 12/11/2005

MessageSujet: The Rebel Fleet, Laniakea Supercluster et Gabriela Mistral.   Jeu 17 Mai à 9:02

Death, posthumous tributes and legacy...

A supercluster is a large group of smaller galaxy clusters or galaxy groups;[1] it is among the largest-known structures of the cosmos. The Milky Way is part of the Local Group galaxy group (which contains more than 54 galaxies), which in turn is part of the Laniakea Supercluster.[2] This supercluster spans over 500 million light-years, while the Local Group spans over 10 million light-years.[1] The number of superclusters in the observable universe is estimated to be 10 million.[3]

Galaxies are grouped into clusters instead of being dispersed randomly. Clusters of galaxies, in turn, are grouped together to form superclusters. Typically, superclusters contain dozens of individual clusters throughout an area of space about 150 million light-years across. Unlike clusters, most superclusters are not bound together by gravity. The component clusters are generally shifting away from each other due to the Hubble flow.

The Milky Way galaxy falls within the Local Group, which is a poor and irregular cluster of galaxies. Poor clusters may contain only a few dozen galaxies, as compared to rich clusters with hundreds or even thousands. The Local Group is in the Local Supercluster (also known as the Virgo Supercluster), which has a diameter of 100 million light-years. The Local Supercluster contains a total of about 1015 times the mass of the Sun and in turn makes up an even bigger supercluster called Laniakea, as revealed by a 2014 study.

The biggest cluster in the observable universe is called the Great Attractor. Its gravity is so strong that the Local Supercluster, including the Milky Way, is moving in a direction towards it at a rate of several hundred kilometers per second. Speeds at this cosmic scale are measured relative to the Hubble flow frame of reference. The biggest supercluster outside the local universe is the Perseus–Pegasus Filament. It contains the Perseus supercluster and it spans about a billion light-years, making it one of the largest known structures in the universe.

Distribution: cosmic voids and sheets
Superclusters are not held together by gravity.[4]

Research has tried to understand the way superclusters are arranged in space. Maps are used to display the positions of 1.6 million galaxies. Three-dimensional maps are used to further understand the positions of these superclusters. To map them three-dimensionally, the position of the galaxy in the sky as well as the galaxy's redshift are used for calculation. The galaxy's redshift is used with Hubble's law to determine its position in three-dimensional space.

It was discovered from those maps that superclusters of galaxies are not spread uniformly across the universe but they seem to lie along filaments. Maps reveal huge voids where there are extremely few galaxies. Some dim galaxies or hydrogen clouds can be found in some voids, but most galaxies are found in sheets between the voids. The voids themselves are often spherical but the superclusters are not. They can range from being 100 million to 400 million light-years in diameter. The pattern of sheets and voids contains information about how galaxy clusters formed in the early universe.

There is a sponge analogy used often that compares a sponge to the pattern of clusters of galaxies in the universe – the holes are the voids and the other parts are the locations of the superclusters.
Existence
The Abell 901/902 supercluster is located a little over two billion light-years from Earth.[5]

The existence of superclusters indicates that the galaxies in the Universe are not uniformly distributed; most of them are drawn together in groups and clusters, with groups containing up to some dozens of galaxies and clusters up to several thousand galaxies. Those groups and clusters and additional isolated galaxies in turn form even larger structures called superclusters.

Their existence was first postulated by George Abell in his 1958 Abell catalogue of galaxy clusters. He called them "second-order clusters", or clusters of clusters.[6]

Superclusters form massive structures of galaxies, called "filaments", "supercluster complexes", "walls" or "sheets", that may span between several hundred million light-years to 10 billion light-years, covering more than 5% of the observable universe. These are the largest known structures to date. Observations of superclusters can give information about the initial condition of the universe, when these superclusters were created. The directions of the rotational axes of galaxies within superclusters may also give insight and information into the early formation process of galaxies in the history of the Universe.[7]

Interspersed among superclusters are large voids of space where few galaxies exist. Superclusters are frequently subdivided into groups of clusters called galaxy groups and clusters.
List of superclusters
Galaxy supercluster Data Notes
Laniakea Supercluster

z = 0.000
Length = 153 Mpc (500 million light-years)

The Laniakea Supercluster is the supercluster that contains the Virgo Cluster, Local Group, and by extension on the latter, our galaxy; the Milky Way.[2]
Virgo Supercluster

z= 0.000
Length = 33 Mpc (110 million light-years)

It contains the Local Group with our galaxy, the Milky Way. It also contains the Virgo Cluster near its center, and is sometimes called the Local Supercluster. It is thought to contain over 47,000 galaxies.

In 2014, the newly announced Laniakea Supercluster subsumed the Virgo Supercluster, which became a component of the new supercluster.[8]
Hydra-Centaurus Supercluster It is composed of two lobes, sometimes also referred to as superclusters, or sometimes the entire supercluster is referred to by these other two names

Hydra Supercluster
Centaurus Supercluster

In 2014, the newly announced Laniakea Supercluster subsumed the Hydra-Centaurus Supercluster, which became a component of the new supercluster.[8]
Pavo-Indus Supercluster

In 2014, the newly announced Laniakea Supercluster subsumed the Pavo-Indus Supercluster, which became a component of the new supercluster.[8]
Southern Supercluster

Includes Fornax Cluster (S373), Dorado and Eridanus clouds.
Saraswati Supercluster Distance = 4000 Million light years (1.2 Gigaparsecs)

Length = 652 Million Light-year
The Saraswati Supercluster consists of 43 massive galaxy clusters such as Abell 2361 and has a mass of about 2 x 1016 and is seen in the Pisces constellation
Nearby superclusters
Galaxy supercluster Data Notes
Perseus-Pisces Supercluster
Coma Supercluster Forms most of the CfA Homunculus, the center of the CfA2 Great Wall galaxy filament
Sculptor Superclusters SCl 9
Hercules Superclusters SCl 160
Leo Supercluster SCl 93
Ophiuchus Supercluster

17h 10m −22°
cz=8500–9000 km/s (centre)
18 Mpc x 26 Mpc

Forming the far wall of the Ophiuchus Void, it may be connected in a filament, with the Pavo-Indus-Telescopium Supercluster and the Hercules Supercluster. This supercluster is centered on the cD cluster Ophiuchus Cluster, and has at least two more galaxy clusters, four more galaxy groups, several field galaxies, as members.[9]
Shapley Supercluster

z=0.046.(650 Mly away)

The second supercluster found, after the Local Supercluster.
Distant superclusters
Galaxy supercluster Data Notes
Pisces-Cetus Supercluster
Boötes Supercluster SCl 138
Horologium Supercluster

z=0.063 (700 Mly)
Length = 550 Mly

The entire supercluster is referred to as the Horologium-Reticulum Supercluster
Corona Borealis Supercluster

z=0.07[10]


Columba Supercluster
Aquarius Supercluster
Aquarius B Supercluster
Aquarius-Capricornus Supercluster
Aquarius-Cetus Supercluster
Bootes A Supercluster
Caelum Supercluster

z=0.126 (1.4 Gly)
Length = 910 Mly

The largest galaxy supercluster
Draco Supercluster
Draco-Ursa Major Supercluster
Fornax-Eridanus Supercluster
Grus Supercluster
Leo A Supercluster
Leo-Sextans Supercluster
Leo-Virgo Supercluster SCl 107
Microscopium Supercluster SCl 174
Pegasus-Pisces Supercluster SCl 3
Perseus-Pisces Supercluster SCl 40
Pisces-Aries Supercluster
Ursa Majoris Supercluster
Virgo-Coma Supercluster SCl 111
Incredibly distant superclusters
Galaxy supercluster Data Notes
Lynx Supercluster z=1.27 Discovered in 1999[11] (as ClG J0848+4453, a name now used to describe the western cluster, with ClG J0849+4452 being the eastern one),[12] it contains at least two clusters RXJ 0848.9+4452 (z=1.26) and RXJ 0848.6+4453 (z=1.27) . At the time of discovery, it became the most distant known supercluster.[13] Additionally, seven smaller groups of galaxies are associated with the supercluster.[14]
SCL @ 1338+27 at z=1.1

z=1.1

Length=70Mpc
A rich supercluster with several galaxy clusters was discovered around an unusual concentration of 23 QSOs at z=1.1 in 2001. The size of the complex of clusters may indicate a wall of galaxies exists there, instead of a single supercluster. The size discovered approaches the size of the CfA2 Great Wall filament. At the time of the discovery, it was the largest and most distant supercluster beyond z=0.5 [15][16]
SCL @ 1604+43 at z=0.9 z=0.91 This supercluster at the time of its discovery was the largest supercluster found so deep into space, in 2000. It consisted of two known rich clusters and one newly discovered cluster as a result of the study that discovered it. The then known clusters were Cl 1604+4304 (z=0.897) and Cl 1604+4321 (z=0.924), which then known to have 21 and 42 known galaxies respectively. The then newly discovered cluster was located at 16h 04m 25.7s, +43° 14′ 44.7″[17]
SCL @ 0018+16 at z=0.54 in SA26 z=0.54 This supercluster lies around radio galaxy 54W084C (z=0.544) and is composed of at least three large clusters, CL 0016+16 (z=0.5455), RX J0018.3+1618 (z=0.5506), RX J0018.8+1602 .[18]
MS 0302+17

z=0.42

Length=6Mpc
This supercluster has at least three member clusters, the eastern cluster CL 0303+1706, southern cluster MS 0302+1659 and northern cluster MS 0302+1717.[19]
Diagram
A diagram of Earth's location in the observable Universe and neighbouring superclusters of galaxies. (Click here for smaller image.)
See also

Cosmology portal Astronomy portal

Wikimedia Commons has media related to Superclusters of galaxies.

Galaxy
Galaxy cloud
Galaxy cluster
Galaxy filament
Galaxy group
Illustris project
Large-scale structure of the cosmos

References

Cain, Fraser (4 May 2009). "Local Group". Universe Today. Retrieved 6 December 2015.
Earth's new address: 'Solar System, Milky Way, Laniakea' / Nature
"The Universe within 14 billion Light Years". Atlas of the Universe. Retrieved 6 December 2015.
"A colossal cluster". www.spacetelescope.org. Retrieved 9 April 2018.
"An Intergalactic Heavyweight". ESO Picture of the Week. Retrieved 12 February 2013.
Abell, George O. (1958). "The distribution of rich clusters of galaxies. A catalogue of 2,712 rich clusters found on the National Geographic Society Palomar Observatory Sky Survey". The Astrophysical Journal Supplement Series. 3: 211–88. Bibcode:1958ApJS....3..211A. doi:10.1086/190036.
Hu, F. X.; et al. (2006). "Orientation of Galaxies in the Local Supercluster: A Review". Astrophysics and Space Science. 302 (1–4): 43–59. arXiv:astro-ph/0508669 Freely accessible. Bibcode:2006Ap&SS.302...43H. doi:10.1007/s10509-005-9006-7.
R. Brent Tully; Helene Courtois; Yehuda Hoffman; Daniel Pomarède (2 September 2014). "The Laniakea supercluster of galaxies". Nature (published 4 September 2014). 513 (7516): 71. arXiv:1409.0880 Freely accessible. Bibcode:2014Natur.513...71T. doi:10.1038/nature13674. PMID 25186900.
Hasegawa, T.; et al. (2000). "Large-scale structure of galaxies in the Ophiuchus region". Monthly Notices of the Royal Astronomical Society. 316 (2): 326–344. Bibcode:2000MNRAS.316..326H. doi:10.1046/j.1365-8711.2000.03531.x.
Postman, M.; Geller, M. J.; Huchra, J. P. (1988). "The dynamics of the Corona Borealis supercluster". Astronomical Journal. 95: 267–83. Bibcode:1988AJ.....95..267P. doi:10.1086/114635.
Rosati, P.; et al. (1999). "An X-Ray-Selected Galaxy Cluster at z = 1.26". The Astronomical Journal. 118 (1): 76–85. arXiv:astro-ph/9903381 Freely accessible. Bibcode:1999AJ....118...76R. doi:10.1086/300934.
"Lynx Supercluster". SIMBAD.
Nakata, F.; et al. (2004). Discovery of a large-scale clumpy structure of the Lynx supercluster at z∼1.27. Proceedings of the International Astronomical Union. 2004. Cambridge University Press. pp. 29–33. Bibcode:2004ogci.conf...29N. doi:10.1017/S1743921304000080. ISBN 0-521-84908-X.
Ohta, K.; et al. (2003). "Optical Identification of the ASCA Lynx Deep Survey: An Association of Quasi-Stellar Objects and a Supercluster at z = 1.3?". The Astrophysical Journal. 598: 210–215. arXiv:astro-ph/0308066 Freely accessible. Bibcode:2003ApJ...598..210O. doi:10.1086/378690.
Tanaka, I. (2004). "Subaru Observation of a Supercluster of Galaxies and QSOS at Z = 1.1". Studies of Galaxies in the Young Universe with New Generation Telescope, Proceedings of Japan-German Seminar, held in Sendai, Japan, July 24–28, 2001. pp. 61–64. Bibcode:2004sgyu.conf...61T.
Tanaka, I.; Yamada, T.; Turner, E. L.; Suto, Y. (2001). "Superclustering of Faint Galaxies in the Field of a QSO Concentration at z ~ 1.1". The Astrophysical Journal. 547 (2): 521–530. arXiv:astro-ph/0009229 Freely accessible. Bibcode:2001ApJ...547..521T. doi:10.1086/318430.
Lubin, L. M.; et al. (2000). "A Definitive Optical Detection of a Supercluster at z ≈ 0.91". The Astrophysical Journal. 531 (1): L5–L8. arXiv:astro-ph/0001166 Freely accessible. Bibcode:2000ApJ...531L...5L. doi:10.1086/312518. PMID 10673401.
Connolly, A. J.; et al. (1996). "Superclustering at Redshift z = 0.54". The Astrophysical Journal Letters. 473 (2): L67–L70. arXiv:astro-ph/9610047 Freely accessible. Bibcode:1996ApJ...473L..67C. doi:10.1086/310395.

University of Hawaii, "The MS0302+17 Supercluster", Nick Kaiser. Retrieved 15 September 2009.

Freedman, Roger; Gellar, Robert M.; Kaufmann, William III (2015). "Galaxies". Universe (10th ed.). New York: W.H. Freedman. ISBN 978-1-319-04238-7.

External links

Media related to Superclusters of galaxies at Wikimedia Commons

Overview of local superclusters
The Nearest Superclusters
Universe family tree: Supercluster
Superclusters - Large Scale Structures

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Galaxies
Morphology

Disc galaxy
Lenticular galaxy

barred
unbarred

Spiral galaxy

Anemic galaxy
barred
flocculent
grand design
intermediate
Magellanic
unbarred

Dwarf galaxy
elliptical irregular spheroidal spiral Elliptical galaxy
cD-galaxy Irregular galaxy
barred Peculiar galaxy Ring galaxy
Polar

Structure

Active galactic nucleus (AGN) Bar Bulge Dark matter halo Disc Galactic halo
corona Galactic plane Interstellar medium Protogalaxy Spiral arm Supermassive black hole

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LAE LIRG Starburst galaxy
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LSB UDG

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Lists

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See also

Dark galaxy Extragalactic astronomy Faint blue galaxy Galactic astronomy Galactic center Galactic coordinate system Galactic empire Galactic habitable zone Galactic magnetic fields Galactic orientation Galactic quadrant Galactic ridge Galaxy color–magnitude diagram Galaxy formation and evolution Galaxy rotation curve Illustris project Intergalactic dust Intergalactic stars Intergalactic travel Population III stars
Cosmos Redshift 7 galaxy

Lucila Godoy Alcayaga (7 April 1889 – 10 January 1957), known by her pseudonym Gabriela Mistral (Spanish: [ɡaˈβɾjela misˈtɾal]), was a Chilean poet-diplomat, educator and humanist. In 1945 she became the first Latin American author to receive a Nobel Prize in Literature, "for her lyric poetry which, inspired by powerful emotions, has made her name a symbol of the idealistic aspirations of the entire Latin American world". Some central themes in her poems are nature, betrayal, love, a mother's love, sorrow and recovery, travel, and Latin American identity as formed from a mixture of Native American and European influences. Her portrait also appears on the 5,000 Chilean peso bank note.

Early life

Mistral was born in Vicuña, Chile,[1] but was raised in the small Andean village of Montegrande, where she attended a primary school taught by her older sister, Emelina Molina. She respected her sister greatly, despite the many financial problems that Emelina brought her in later years. Her father, Juan Gerónimo Godoy Villanueva, was also a schoolteacher. He abandoned the family before she was three years old, and died, long since estranged from the family, in 1911. Throughout her early years she was never far from poverty. By age fifteen, she was supporting herself and her mother, Petronila Alcayaga, a seamstress, by working as a teacher's aide in the seaside town of Compañia Baja, near La Serena, Chile.

In 1904 Mistral published some early poems, such as Ensoñaciones ("Dreams"), Carta Íntima ("Intimate Letter") and Junto al Mar ("By the Sea"), in the local newspaper El Coquimbo: Diario Radical, and La Voz de Elqui using a range of pseudonyms and variations on her civil name.

In 1906, Mistral met Romelio Ureta, her first love, who killed himself in 1909. Shortly after, her second love married someone else. This heartbreak was reflected in her early poetry and earned Mistral her first recognized literary work in 1914 with Sonnets on Death (Sonnets de la muerte). Mistral was awarded first prize in a national literary contest Juegos Florales in Santiago (the capital of Chile). Writing about his suicide led the poet to consider death and life more broadly than previous generations of Latin American poets. While Mistral had passionate friendships with various men and women, and these impacted her writings, she was secretive about her emotional life.

She had been using the pen name Gabriela Mistral since June 1908 for much of her writing. After winning the Juegos Florales she infrequently used her given name of Lucila Godoy for her publications. She formed her pseudonym from the names of two of her favorite poets, Gabriele D'Annunzio and Frédéric Mistral or, as another story has it, from a composite of the Archangel Gabriel and the Mistral wind of Provence.

In 1922, Mistral released her first book, Desolation (Desolacion), with the help of the Director of Hispanic Institute of New York, Frederico de Onis. It was a collection of poems that encompassed motherhood, religion, nature, morality and love of children. Her personal sorrow was present in the poems and her International reputation was established. Her work was a turn from modernism in Latin America and was marked by critics as direct, yet simplistic. In 1924, she released her second book, Tenderness (Ternura).
Career as an educator
Gabriela Mistral during her youth

Mistral's meteoric rise in Chile's national school system plays out against the complex politics of Chile in the first two decades of the 20th century. In her adolescence, the need for teachers was so great, and the number of trained teachers was so small, especially in the rural areas, that anyone who was willing could find work as a teacher. Access to good schools was difficult, however, and the young woman lacked the political and social connections necessary to attend the Normal School: She was turned down, without explanation, in 1907. She later identified the obstacle to her entry as the school's chaplain, Father Ignacio Munizaga, who was aware of her publications in the local newspapers, her advocacy of liberalizing education and giving greater access to the schools to all social classes.

Although her formal education had ended by 1900, she was able to get work as a teacher thanks to her older sister, Emelina, who had likewise begun as a teacher's aide and was responsible for much of the poet's early education. The poet was able to rise from one post to another because of her publications in local and national newspapers and magazines. Her willingness to move was also a factor. Between the years 1906 and 1912 she had taught, successively, in three schools near La Serena, then in Barrancas, then Traiguén in 1910, and in Antofagasta in the desert north, in 1911. By 1912 she had moved to work in a liceo, or high school, in Los Andes, where she stayed for six years and often visited Santiago. In 1918 Pedro Aguirre Cerda, then Minister of Education, and a future president of Chile, promoted her appointment to direct a liceo in Punta Arenas. She moved on to Temuco in 1920, then to Santiago, where in 1921, she defeated a candidate connected with the Radical Party, Josefina Dey del Castillo to be named director of Santiago's Liceo #6, the newest and most prestigious girls' school in Chile. Controversies over the nomination of Gabriela Mistral to the highly coveted post in Santiago were among the factors that made her decide to accept an invitation to work in Mexico in 1922, with that country's Minister of Education, José Vasconcelos. He had her join in the nation's plan to reform libraries and schools, to start a national education system. That year she published Desolación in New York, which further promoted the international acclaim she had already been receiving thanks to her journalism and public speaking. A year later she published Lecturas para Mujeres (Readings for Women), a text in prose and verse that celebrates Latin America from the broad, Americanist perspective developed in the wake of the Mexican Revolution.

Following almost two years in Mexico she traveled from Laredo, Texas to Washington D.C., where she addressed the Pan American Union, went on to New York, then toured Europe: In Madrid she published Ternura (Tenderness), a collection of lullabies and rondas written for an audience of children, parents, and other poets. In early 1925 she returned to Chile, where she formally retired from the nation's education system, and received a pension. It wasn't a moment too soon: The legislature had just agreed to the demands of the teachers union, headed by Mistral's lifelong rival, Amanda Labarca Hubertson, that only university-trained teachers should be given posts in the schools. The University of Chile had granted her the academic title of Spanish Professor in 1923, although her formal education ended before she was 12 years old. Her autodidacticism was remarkable, a testimony to the flourishing culture of newspapers, magazines, and books in provincial Chile, as well as to her personal determination and verbal genius.

Pablo Neruda, internationally recognized poet, was one of her students.
International work and recognition
Gabriela during the 1950s.

Mistral's international stature made it highly unlikely that she would remain in Chile. In mid-1925 she was invited to represent Latin America in the newly formed Institute for Intellectual Cooperation of the League of Nations. With her relocation to France in early 1926 she was effectively an exile for the rest of her life. She made a living, at first, from journalism and then giving lectures in the United States and in Latin America, including Puerto Rico. She variously toured the Caribbean, Brazil, Uruguay, and Argentina, among other places.

Mistral lived primarily in France and Italy between 1926 and 1932. During these years she worked for the League for Intellectual Cooperation of the League of Nations, attending conferences of women and educators throughout Europe and occasionally in the Americas. She held a visiting professorship at Barnard College of Columbia University in 1930–1931, worked briefly at Middlebury College and Vassar College in 1931, and was warmly received at the University of Puerto Rico at Rio Piedras, where she variously gave conferences or wrote, in 1931, 1932, and 1933.

Like many Latin American artists and intellectuals, Mistral served as a consul from 1932 until her death, working in Naples, Madrid, Lisbon, Nice,[1] Petrópolis, Los Angeles, Santa Barbara, Veracruz, Rapallo, and New York. As consul in Madrid, she had occasional professional interactions with another Chilean consul and Nobel Prize recipient, Pablo Neruda, and she was among the earlier writers to recognize the importance and originality of his work, which she had known while he was a teenager and she was school director in his hometown of Temuco.

She published hundreds of articles in magazines and newspapers throughout the Spanish-speaking world. Among her confidants were Eduardo Santos, President of Colombia, all of the elected Presidents of Chile from 1922 to her death in 1957, Eduardo Frei Montalva, Chilean elected president in 1964 and Eleanor Roosevelt.

The poet's second major volume of poetry, Tala, appeared in 1938, published in Buenos Aires with the help of longtime friend and correspondent Victoria Ocampo. The proceeds for the sale were devoted to children orphaned by the Spanish Civil War. This volume includes many poems celebrating the customs and folklore of Latin America as well as Mediterranean Europe. Mistral uniquely fuses these locales and concerns, a reflection of her identification as "una mestiza de vasco," her European Basque-Indigenous Amerindian background.

On 14 August 1943, Mistral's 17-year-old nephew, Juan Miguel Godoy, killed himself. Mistral considered Juan Miguel as a son. The grief of this death, as well as her responses to tensions of World War II and then the Cold War in Europe and the Americas, are all reflected in the last volume of poetry published in her lifetime, Lagar, which appeared in a truncated form in 1954. A final volume of poetry, Poema de Chile, was edited posthumously by her friend Doris Dana and published in 1967. Poema de Chile describes the poet's return to Chile after death, in the company of an Indian boy from the Atacama desert and an Andean deer, the huemul. This collection of poetry anticipates the interests in objective description and re-vision of the epic tradition just then becoming evident among poets of the Americas, all of whom Mistral read carefully.
Gabriela Mistral Early Childhood Center in Houston[2]

On 15 November 1945, Mistral became the first Latin American, and fifth woman, to receive the Nobel Prize in Literature. She received the award in person from King Gustav of Sweden on 10 December 1945. In 1947 she received a doctor honoris causa from Mills College, Oakland, California. In 1951 she was awarded the National Literature Prize in Chile.

Poor health somewhat slowed Mistral's traveling. During the last years of her life she made her home in the town of Roslyn, New York; in early January 1957 she transferred to Hempstead, New York, where she died from pancreatic cancer on 10 January 1957, aged 67. Her remains were returned to Chile nine days later. The Chilean government declared three days of national mourning, and hundreds of thousands of Chileans came to pay her their respects.

Some of Mistral's best known poems include Piececitos de Niño, Balada, Todas Íbamos a ser Reinas, La Oración de la Maestra, El Ángel Guardián, Decálogo del Artista and La Flor del Aire. She wrote and published some 800 essays in magazines and newspapers; she was also a well-known correspondent and highly regarded orator both in person and over the radio.

Mistral may be most widely quoted in English for Su Nombre es Hoy (His Name is Today):

“We are guilty of many errors and many faults, but our worst crime is abandoning the children, neglecting the fountain of life. Many of the things we need can wait. The child cannot. Right now is the time his bones are being formed, his blood is being made, and his senses are being developed. To him we cannot answer ‘Tomorrow,’ his name is today.”

Characteristics of her work

Mistral's work is characterized by including gray tones in his literature, sadness and bitterness are recurrent feelings on it. These are evoked in his writings as the reflection of a hard childhood which was plagued by deprivation coupled with a lack of affection in her home. However, Gabriela Mistral also shows through in her writings a great affection for children, since in her youth she became a teacher in a rural school. Religion was also reflected in his literature as it had great influence of Catholicism in her life, however, she always reflected a more neutral stance regarding the conception of religion, so we can find in their literature gray tones combined with feelings of love and piety, making her into one of the worthiest representatives of Latin American literature of twentieth century.[3]

A galaxy is a gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter.

Su Nombre es Hoy (His Name is Today):

“We are guilty of many errors and many faults, but our worst crime is abandoning the children, neglecting the fountain of life. Many of the things we need can wait. The child cannot. Right now is the time his bones are being formed, his blood is being made, and his senses are being developed. To him we cannot answer ‘Tomorrow,’ his name is today.”
Lucila Godoy Alcayaga by her pseudonym Gabriela Mistral.

"See yonder, lo, the Galaxyë
Which men clepeth the Milky Wey,
For hit is whyt."
— Geoffrey Chaucer, The House of Fame

Other morphologies

Peculiar galaxies are galactic formations that develop unusual properties due to tidal interactions with other galaxies.
A ring galaxy has a ring-like structure of stars and interstellar medium surrounding a bare core. A ring galaxy is thought to occur when a smaller galaxy passes through the core of a spiral galaxy.[73] Such an event may have affected the Andromeda Galaxy, as it displays a multi-ring-like structure when viewed in infrared radiation.[74]
A lenticular galaxy is an intermediate form that has properties of both elliptical and spiral galaxies. These are categorized as Hubble type S0, and they possess ill-defined spiral arms with an elliptical halo of stars[75] (barred lenticular galaxies receive Hubble classification SB0.)
Irregular galaxies are galaxies that can not be readily classified into an elliptical or spiral morphology.
An Irr-I galaxy has some structure but does not align cleanly with the Hubble classification scheme.
Irr-II galaxies do not possess any structure that resembles a Hubble classification, and may have been disrupted.[76] Nearby examples of (dwarf) irregular galaxies include the Magellanic Clouds.
An ultra diffuse galaxy (UDG) is an extremely-low-density galaxy. The galaxy may be the same size as the Milky Way but has a visible star count of only 1% of the Milky Way. The lack of luminosity is because there is a lack of star-forming gas in the galaxy which results in old stellar populations.

Awards and honors

1914: Juegos Florales, Sonetos de la Muerte
1945: Nobel Prize in Literature
1951: Chilean National Prize for Literature

The Venezuelan writer and diplomat who worked under the name Lucila Palacios took her nom de plume in honour of Mistral's original name.[5]
Works

Each year links to its corresponding "[year] in poetry" or "[year] in literature" article:

1914: Sonetos de la muerte ("Sonnets of Death")[6]
1922: Desolación ("Despair"), including "Decalogo del artista", New York : Instituto de las Españas[7]
1923: Lecturas para Mujeres ("Readings for Women")[8]
1924: Ternura: canciones de niños, Madrid: Saturnino Calleja[7]
1934: Nubes Blancas y Breve Descripción de Chile (1934)
1938: Tala ("Harvesting"[9]), Buenos Aires: Sur[7]
1941: Antología: Selección de Gabriela Mistral, Santiago, Chile: Zig Zag[10]
1952: Los sonetos de la muerte y otros poemas elegíacos, Santiago, Chile: Philobiblion[7]
1954: Lagar, Santiago, Chile
1957: Recados: Contando a Chile, Santiago, Chile: Editorial del Pacífico[7]Croquis mexicanos; Gabriela Mistral en México, México City: Costa-Amic[7]
1958: Poesías completas, Madrid : Aguilar[7]
1967: Poema de Chile ("Poem of Chile"), published posthumously[11]
1992: Lagar II, published posthumously, Santiago, Chile: Biblioteca Nacional[12]

See also

flagChile portal Biography portal iconPoetry portal

Barnard College, repository for part of Mistral's personal library, given by Doris Dana in 1978.
Land of poets
List of female Nobel laureates

John Williams - Who Are You ?
https://www.youtube.com/watch?v=5MEKrkOzy6o

Within a billion years of a galaxy's formation, key structures begin to appear. Globular clusters, the central supermassive black hole, and a galactic bulge of metal-poor Population II stars form. The creation of a supermassive black hole appears to play a key role in actively regulating the growth of galaxies by limiting the total amount of additional matter added.[110] During this early epoch, galaxies undergo a major burst of star formation.[111]

During the following two billion years, the accumulated matter settles into a galactic disc.[112] A galaxy will continue to absorb infalling material from high-velocity clouds and dwarf galaxies throughout its life.[113] This matter is mostly hydrogen and helium. The cycle of stellar birth and death slowly increases the abundance of heavy elements, eventually allowing the formation of planets.[114]
Hubble eXtreme Deep Field (XDF)
XDF view field compared to the angular size of the Moon. Several thousand galaxies, each consisting of billions of stars, are in this small view.
XDF (2012) view: Each light speck is a galaxy, some of which are as old as 13.2 billion years[115] – the observable universe is estimated to contain 200 billion to 2 trillion galaxies.
XDF image shows (from left) fully mature galaxies, nearly mature galaxies (from 5 to 9 billion years ago), and protogalaxies, blazing with young stars (beyond 9 billion years).

The evolution of galaxies can be significantly affected by interactions and collisions. Mergers of galaxies were common during the early epoch, and the majority of galaxies were peculiar in morphology.[116] Given the distances between the stars, the great majority of stellar systems in colliding galaxies will be unaffected. However, gravitational stripping of the interstellar gas and dust that makes up the spiral arms produces a long train of stars known as tidal tails. Examples of these formations can be seen in NGC 4676[117] or the Antennae Galaxies.[118]

The Milky Way galaxy and the nearby Andromeda Galaxy are moving toward each other at about 130 km/s, and—depending upon the lateral movements—the two might collide in about five to six billion years. Although the Milky Way has never collided with a galaxy as large as Andromeda before, evidence of past collisions of the Milky Way with smaller dwarf galaxies is increasing.[119]

Such large-scale interactions are rare. As time passes, mergers of two systems of equal size become less common. Most bright galaxies have remained fundamentally unchanged for the last few billion years, and the net rate of star formation probably also peaked approximately ten billion years ago.[120]

https://en.wikipedia.org/wiki/Galaxy
https://en.wikipedia.org/wiki/Supercluster
https://en.wikipedia.org/wiki/Laniakea_Supercluster

Star Wars - Sound of the Force...
https://www.youtube.com/watch?v=Itov0tisWHk

ÉLECTRIQUE ET LUMIÈRE, D'ACIER ET DE SANG, DE SÈVE ET DE FEU: LA FORCE EST UN SENTIMENT LIÉ AUX NATURES DE LA VIE. YAHVÉ ET Y'BECCA OU L'ALBATROS ET THE FIREFLY...

Firefly - Mal's song - YouTube
https://www.youtube.com/watch?v=qc4kaRzLIxQ

SENTIMENTS DU
CITOYEN TIGNARD YANIS
PAR
Y'BECCA et WIKIPEDIA.

A supercluster. Laniakea Supercluster, Lucila Godoy Alcayaga et Galaxy.
http://leclandesmouettes.bbflash.net/t816-laniakea-supercluster-lucila-godoy-alcayaga-et-galaxy#8948 … Star Wars - The Rebel Fleet. https://www.youtube.com/watch?v=7XMrW1j1W6U
FACTION ET PHALANGE ou Jacques Maritain et Falange Nacional. http://leclandesmouettes.bbflash.net/t815-faction-et-phalange-ou-jacques-maritain-et-falange-nacional
Y'BECCA.
TAY
Revenir en haut Aller en bas
Voir le profil de l'utilisateur http://www.atelier-yannistignard.com
yanis la chouette



Nombre de messages : 6759
Localisation : http://yanis.tignard.free.fr
Date d'inscription : 12/11/2005

MessageSujet: Re: The Rebel Fleet, Laniakea Supercluster et Gabriela Mistral.   Jeu 17 Mai à 9:06

The observable universe is a spherical region of the universe comprising all matter that can be observed from Earth at the present time, because electromagnetic radiation from these objects has had time to reach Earth since the beginning of the cosmological expansion. There are at least 2 trillion galaxies in the observable universe.[7][8] Assuming the universe is isotropic, the distance to the edge of the observable universe is roughly the same in each direction. That is, the observable universe is a spherical volume (a ball) centered on the observer. Every location in the universe has its own observable universe, which may or may not overlap with the one centered on Earth.

The universe versus the observable universe

The word observable in this sense does not refer to the capability of modern technology to detect light or other information from an object, or whether there is anything to be detected. It refers to the physical limit created by the speed of light itself. Because no signals can travel faster than light, any object farther away from us than light could travel in the age of the universe (estimated as of 2015 around 13.799±0.021 billion years[5]) simply cannot be detected, as they have not reached us yet. Sometimes astrophysicists distinguish between the visible universe, which includes only signals emitted since recombination—and the observable universe, which includes signals since the beginning of the cosmological expansion (the Big Bang in traditional physical cosmology, the end of the inflationary epoch in modern cosmology).

According to calculations, the current comoving distance—proper distance, which takes into account that the universe has expanded since the light was emitted—to particles from which the cosmic microwave background radiation (CMBR) was emitted, which represent the radius of the visible universe, is about 14.0 billion parsecs (about 45.7 billion light-years), while the comoving distance to the edge of the observable universe is about 14.3 billion parsecs (about 46.6 billion light-years),[9] about 2% larger. The radius of the observable universe is therefore estimated to be about 46.5 billion light-years[10][11] and its diameter about 28.5 gigaparsecs (93 billion light-years, 8.8×1023 kilometres or 5.5×1023 miles).[12] The total mass of ordinary matter in the universe can be calculated using the critical density and the diameter of the observable universe to be about 1.5×1053 kg.[13]

Since the expansion of the universe is known to accelerate and will become exponential in the future, the light emitted from all distant objects past some time dependent on their current redshift will never reach the Earth. In the future all currently observable objects will slowly freeze in time while emitting progressively redder and fainter light. For instance, objects with the current redshift z from 5 to 10 will remain observable for no more than 4–6 billion years. In addition, light emitted by objects situated beyond a certain comoving distance (currently about 19 billion parsecs) will never reach Earth.[14]

Part of a series on
Physical cosmology
Full-sky image derived from nine years' WMAP data

Big Bang · Universe
Age of the universe
Chronology of the universe

Early universe
[show]
Expansion · Future
[show]
Components · Structure
[hide]
Components

Lambda-CDM model
Baryonic matter
Energy
Radiation
Dark energy
Quintessence
Phantom energy
Dark matter
Cold dark matter
Warm dark matter
Hot dark matter
Dark radiation

Structure

Shape of the universe
Reionization · Structure formation
Galaxy formation
Large-scale structure
Large quasar group
Galaxy filament
Supercluster
Galaxy cluster
Galaxy group
Local Group
Void

Incredibly distant superclusters
Galaxy supercluster Data Notes
Lynx Supercluster z=1.27 Discovered in 1999[11] (as ClG J0848+4453, a name now used to describe the western cluster, with ClG J0849+4452 being the eastern one),[12] it contains at least two clusters RXJ 0848.9+4452 (z=1.26) and RXJ 0848.6+4453 (z=1.27) . At the time of discovery, it became the most distant known supercluster.[13] Additionally, seven smaller groups of galaxies are associated with the supercluster.[14]
SCL @ 1338+27 at z=1.1

z=1.1

Length=70Mpc
A rich supercluster with several galaxy clusters was discovered around an unusual concentration of 23 QSOs at z=1.1 in 2001. The size of the complex of clusters may indicate a wall of galaxies exists there, instead of a single supercluster. The size discovered approaches the size of the CfA2 Great Wall filament. At the time of the discovery, it was the largest and most distant supercluster beyond z=0.5 [15][16]
SCL @ 1604+43 at z=0.9 z=0.91 This supercluster at the time of its discovery was the largest supercluster found so deep into space, in 2000. It consisted of two known rich clusters and one newly discovered cluster as a result of the study that discovered it. The then known clusters were Cl 1604+4304 (z=0.897) and Cl 1604+4321 (z=0.924), which then known to have 21 and 42 known galaxies respectively. The then newly discovered cluster was located at 16h 04m 25.7s, +43° 14′ 44.7″[17]
SCL @ 0018+16 at z=0.54 in SA26 z=0.54 This supercluster lies around radio galaxy 54W084C (z=0.544) and is composed of at least three large clusters, CL 0016+16 (z=0.5455), RX J0018.3+1618 (z=0.5506), RX J0018.8+1602 .[18]
MS 0302+17

z=0.42

Length=6Mpc
This supercluster has at least three member clusters, the eastern cluster CL 0303+1706, southern cluster MS 0302+1659 and northern cluster MS 0302+1717.[19]

Some parts of the universe are too far away for the light emitted since the Big Bang to have had enough time to reach Earth, so these portions of the universe lie outside the observable universe. In the future, light from distant galaxies will have had more time to travel, so additional regions will become observable. However, due to Hubble's law, regions sufficiently distant from the Earth are expanding away from it faster than the speed of light (special relativity prevents nearby objects in the same local region from moving faster than the speed of light with respect to each other, but there is no such constraint for distant objects when the space between them is expanding; see uses of the proper distance for a discussion) and furthermore the expansion rate appears to be accelerating due to dark energy. Assuming dark energy remains constant (an unchanging cosmological constant), so that the expansion rate of the universe continues to accelerate, there is a "future visibility limit" beyond which objects will never enter our observable universe at any time in the infinite future, because light emitted by objects outside that limit would never reach the Earth. (A subtlety is that, because the Hubble parameter is decreasing with time, there can be cases where a galaxy that is receding from the Earth just a bit faster than light does emit a signal that reaches the Earth eventually.[11][15]) This future visibility limit is calculated at a comoving distance of 19 billion parsecs (62 billion light-years), assuming the universe will keep expanding forever, which implies the number of galaxies that we can ever theoretically observe in the infinite future (leaving aside the issue that some may be impossible to observe in practice due to redshift, as discussed in the following paragraph) is only larger than the number currently observable by a factor of 2.36.[16]
Artist's logarithmic scale conception of the observable universe with the Solar System at the center, inner and outer planets, Kuiper belt, Oort cloud, Alpha Centauri, Perseus Arm, Milky Way galaxy, Andromeda galaxy, nearby galaxies, Cosmic Web, Cosmic microwave radiation and the Big Bang's invisible plasma on the edge.

Though in principle more galaxies will become observable in the future, in practice an increasing number of galaxies will become extremely redshifted due to ongoing expansion, so much so that they will seem to disappear from view and become invisible.[17][18][19] An additional subtlety is that a galaxy at a given comoving distance is defined to lie within the "observable universe" if we can receive signals emitted by the galaxy at any age in its past history (say, a signal sent from the galaxy only 500 million years after the Big Bang), but because of the universe's expansion, there may be some later age at which a signal sent from the same galaxy can never reach the Earth at any point in the infinite future (so, for example, we might never see what the galaxy looked like 10 billion years after the Big Bang),[20] even though it remains at the same comoving distance (comoving distance is defined to be constant with time—unlike proper distance, which is used to define recession velocity due to the expansion of space), which is less than the comoving radius of the observable universe.[clarification needed] This fact can be used to define a type of cosmic event horizon whose distance from the Earth changes over time. For example, the current distance to this horizon is about 16 billion light-years, meaning that a signal from an event happening at present can eventually reach the Earth in the future if the event is less than 16 billion light-years away, but the signal will never reach the Earth if the event is more than 16 billion light-years away.[11]

Both popular and professional research articles in cosmology often use the term "universe" to mean "observable universe".[citation needed] This can be justified on the grounds that we can never know anything by direct experimentation about any part of the universe that is causally disconnected from the Earth, although many credible theories require a total universe much larger than the observable universe.[citation needed] No evidence exists to suggest that the boundary of the observable universe constitutes a boundary on the universe as a whole, nor do any of the mainstream cosmological models propose that the universe has any physical boundary in the first place, though some models propose it could be finite but unbounded, like a higher-dimensional analogue of the 2D surface of a sphere that is finite in area but has no edge. It is plausible that the galaxies within our observable universe represent only a minuscule fraction of the galaxies in the universe. According to the theory of cosmic inflation initially introduced by its founder, Alan Guth (and by D. Kazanas [21]), if it is assumed that inflation began about 10−37 seconds after the Big Bang, then with the plausible assumption that the size of the universe before the inflation occurred was approximately equal to the speed of light times its age, that would suggest that at present the entire universe's size is at least 3×1023 times the radius of the observable universe.[22] There are also lower estimates claiming that the entire universe is in excess of 250 times larger than the observable universe[23] and also higher estimates implying that the universe is at least 101010122 times larger than the observable universe.[24]

If the universe is finite but unbounded, it is also possible that the universe is smaller than the observable universe. In this case, what we take to be very distant galaxies may actually be duplicate images of nearby galaxies, formed by light that has circumnavigated the universe. It is difficult to test this hypothesis experimentally because different images of a galaxy would show different eras in its history, and consequently might appear quite different. Bielewicz et al.[25] claims to establish a lower bound of 27.9 gigaparsecs (91 billion light-years) on the diameter of the last scattering surface (since this is only a lower bound, the paper leaves open the possibility that the whole universe is much larger, even infinite). This value is based on matching-circle analysis of the WMAP 7 year data. This approach has been disputed.[26]
Size
Hubble Ultra-Deep Field image of a region of the observable universe (equivalent sky area size shown in bottom left corner), near the constellation Fornax. Each spot is a galaxy, consisting of billions of stars. The light from the smallest, most redshifted galaxies originated nearly 14 billion years ago.

The comoving distance from Earth to the edge of the observable universe is about 14.26 gigaparsecs (46.5 billion light-years or 4.40×1026 meters) in any direction. The observable universe is thus a sphere with a diameter of about 28.5 gigaparsecs[27] (93 Gly or 8.8×1026 m).[28] Assuming that space is roughly flat (in the sense of being a Euclidian space), this size corresponds to a comoving volume of about 1.22×104 Gpc3 (4.22×105 Gly3 or 3.57×1080 m3).[29]

The figures quoted above are distances now (in cosmological time), not distances at the time the light was emitted. For example, the cosmic microwave background radiation that we see right now was emitted at the time of photon decoupling, estimated to have occurred about 380,000 years after the Big Bang,[30][31] which occurred around 13.8 billion years ago. This radiation was emitted by matter that has, in the intervening time, mostly condensed into galaxies, and those galaxies are now calculated to be about 46 billion light-years from us.[9][11] To estimate the distance to that matter at the time the light was emitted, we may first note that according to the Friedmann–Lemaître–Robertson–Walker metric, which is used to model the expanding universe, if at the present time we receive light with a redshift of z, then the scale factor at the time the light was originally emitted is given by[32][33]

a ( t ) = 1 1 + z {\displaystyle \!a(t)={\frac {1}{1+z}}} \!a(t)={\frac {1}{1+z}}.

WMAP nine-year results combined with other measurements give the redshift of photon decoupling as z = 1091.64±0.47,[34] which implies that the scale factor at the time of photon decoupling would be ​1⁄1092.64. So if the matter that originally emitted the oldest CMBR photons has a present distance of 46 billion light-years, then at the time of decoupling when the photons were originally emitted, the distance would have been only about 42 million light-years.
Misconceptions on its size
An example of the misconception that the radius of the observable universe is 13 billion light-years. This plaque appears at the Rose Center for Earth and Space in New York City.

Many secondary sources have reported a wide variety of incorrect figures for the size of the visible universe. Some of these figures are listed below, with brief descriptions of possible reasons for misconceptions about them.

13.8 billion light-years
The age of the universe is estimated to be 13.8 billion years. While it is commonly understood that nothing can accelerate to velocities equal to or greater than that of light, it is a common misconception that the radius of the observable universe must therefore amount to only 13.8 billion light-years. This reasoning would only make sense if the flat, static Minkowski spacetime conception under special relativity were correct. In the real universe, spacetime is curved in a way that corresponds to the expansion of space, as evidenced by Hubble's law. Distances obtained as the speed of light multiplied by a cosmological time interval have no direct physical significance.[35]

15.8 billion light-years
This is obtained in the same way as the 13.8-billion-light-year figure, but starting from an incorrect age of the universe that the popular press reported in mid-2006.[36][37] For an analysis of this claim and the paper that prompted it, see the following reference at the end of this article.[38]

27.6 billion light-years
This is a diameter obtained from the (incorrect) radius of 13.8 billion light-years.

78 billion light-years
In 2003, Cornish et al.[39] found this lower bound for the diameter of the whole universe (not just the observable part), if we postulate that the universe is finite in size due to its having a nontrivial topology,[40][41] with this lower bound based on the estimated current distance between points that we can see on opposite sides of the cosmic microwave background radiation (CMBR). If the whole universe is smaller than this sphere, then light has had time to circumnavigate it since the Big Bang, producing multiple images of distant points in the CMBR, which would show up as patterns of repeating circles.[42] Cornish et al. looked for such an effect at scales of up to 24 gigaparsecs (78 Gly or 7.4×1026 m) and failed to find it, and suggested that if they could extend their search to all possible orientations, they would then "be able to exclude the possibility that we live in a universe smaller than 24 Gpc in diameter". The authors also estimated that with "lower noise and higher resolution CMB maps (from WMAP's extended mission and from Planck), we will be able to search for smaller circles and extend the limit to ~28 Gpc."[39] This estimate of the maximum lower bound that can be established by future observations corresponds to a radius of 14 gigaparsecs, or around 46 billion light-years, about the same as the figure for the radius of the visible universe (whose radius is defined by the CMBR sphere) given in the opening section. A 2012 preprint by most of the same authors as the Cornish et al. paper has extended the current lower bound to a diameter of 98.5% the diameter of the CMBR sphere, or about 26 Gpc.[43]

156 billion light-years
This figure was obtained by doubling 78 billion light-years on the assumption that it is a radius.[44] Because 78 billion light-years is already a diameter (the original paper by Cornish et al. says, "By extending the search to all possible orientations, we will be able to exclude the possibility that we live in a universe smaller than 24 Gpc in diameter," and 24 Gpc is 78 billion light-years),[39] the doubled figure is incorrect. This figure was very widely reported.[44][45][46] A press release from Montana State University–Bozeman, where Cornish works as an astrophysicist, noted the error when discussing a story that had appeared in Discover magazine, saying "Discover mistakenly reported that the universe was 156 billion light-years wide, thinking that 78 billion was the radius of the universe instead of its diameter."[47] As noted above, 78 billion was also incorrect.

180 billion light-years
This estimate combines the erroneous 156-billion-light-year figure with evidence that the M33 Galaxy is actually fifteen percent farther away than previous estimates and that, therefore, the Hubble constant is fifteen percent smaller.[48] The 180-billion figure is obtained by adding 15% to 156 billion light-years.

Large-scale structure
Main article: Cosmic web

Sky surveys and mappings of the various wavelength bands of electromagnetic radiation (in particular 21-cm emission) have yielded much information on the content and character of the universe's structure. The organization of structure appears to follow as a hierarchical model with organization up to the scale of superclusters and filaments. Larger than this (at scales between 30 and 200 megaparsecs[49]), there seems to be no continued structure, a phenomenon that has been referred to as the End of Greatness.[50]
Walls, filaments, nodes, and voids
DTFE reconstruction of the inner parts of the 2dF Galaxy Redshift Survey

The organization of structure arguably begins at the stellar level, though most cosmologists rarely address astrophysics on that scale. Stars are organized into galaxies, which in turn form galaxy groups, galaxy clusters, superclusters, sheets, walls and filaments, which are separated by immense voids, creating a vast foam-like structure[51] sometimes called the "cosmic web". Prior to 1989, it was commonly assumed that virialized galaxy clusters were the largest structures in existence, and that they were distributed more or less uniformly throughout the universe in every direction. However, since the early 1980s, more and more structures have been discovered. In 1983, Adrian Webster identified the Webster LQG, a large quasar group consisting of 5 quasars. The discovery was the first identification of a large-scale structure, and has expanded the information about the known grouping of matter in the universe. In 1987, Robert Brent Tully identified the Pisces–Cetus Supercluster Complex, the galaxy filament in which the Milky Way resides. It is about 1 billion light-years across. That same year, an unusually large region with no galaxies was discovered, the Giant Void, which measures 1.3 billion light-years across. Based on redshift survey data, in 1989 Margaret Geller and John Huchra discovered the "Great Wall",[52] a sheet of galaxies more than 500 million light-years long and 200 million light-years wide, but only 15 million light-years thick. The existence of this structure escaped notice for so long because it requires locating the position of galaxies in three dimensions, which involves combining location information about the galaxies with distance information from redshifts. Two years later, astronomers Roger G. Clowes and Luis E. Campusano discovered the Clowes–Campusano LQG, a large quasar group measuring two billion light-years at its widest point, and was the largest known structure in the universe at the time of its announcement. In April 2003, another large-scale structure was discovered, the Sloan Great Wall. In August 2007, a possible supervoid was detected in the constellation Eridanus.[53] It coincides with the 'CMB cold spot', a cold region in the microwave sky that is highly improbable under the currently favored cosmological model. This supervoid could cause the cold spot, but to do so it would have to be improbably big, possibly a billion light-years across, almost as big as the Giant Void mentioned above.
Computer simulated image of an area of space more than 50 million light-years across, presenting a possible large-scale distribution of light sources in the universe—precise relative contributions of galaxies and quasars are unclear.

Another large-scale structure is the Newfound Blob, a collection of galaxies and enormous gas bubbles that measures about 200 million light-years across.

In 2011, a large quasar group was discovered, U1.11, measuring about 2.5 billion light-years across. On January 11, 2013, another large quasar group, the Huge-LQG, was discovered, which was measured to be four billion light-years across, the largest known structure in the universe at that time.[54] In November 2013, astronomers discovered the Hercules–Corona Borealis Great Wall,[55][56] an even bigger structure twice as large as the former. It was defined by the mapping of gamma-ray bursts.[55][57]
End of Greatness

The End of Greatness is an observational scale discovered at roughly 100 Mpc (roughly 300 million light-years) where the lumpiness seen in the large-scale structure of the universe is homogenized and isotropized in accordance with the Cosmological Principle.[50] At this scale, no pseudo-random fractalness is apparent.[58] The superclusters and filaments seen in smaller surveys are randomized to the extent that the smooth distribution of the universe is visually apparent. It was not until the redshift surveys of the 1990s were completed that this scale could accurately be observed.[50]

The existence of superclusters indicates that the galaxies in the Universe are not uniformly distributed; most of them are drawn together in groups and clusters, with groups containing up to some dozens of galaxies and clusters up to several thousand galaxies. Those groups and clusters and additional isolated galaxies in turn form even larger structures called superclusters.

Their existence was first postulated by George Abell in his 1958 Abell catalogue of galaxy clusters. He called them "second-order clusters", or clusters of clusters.[6]

Superclusters form massive structures of galaxies, called "filaments", "supercluster complexes", "walls" or "sheets", that may span between several hundred million light-years to 10 billion light-years, covering more than 5% of the observable universe. These are the largest known structures to date. Observations of superclusters can give information about the initial condition of the universe, when these superclusters were created. The directions of the rotational axes of galaxies within superclusters may also give insight and information into the early formation process of galaxies in the history of the Universe.[7]

Interspersed among superclusters are large voids of space where few galaxies exist. Superclusters are frequently subdivided into groups of clusters called galaxy groups and clusters.

Levez les yeux ! C'est moi qui passe sur vos têtes,
Diaphane et léger, libre dans le ciel pur ;
L'aile ouverte, attendant le souffle des tempêtes,
Je plonge et nage en plein azur.

Comme un mirage errant, je flotte et je voyage.
Coloré par l'aurore et le soir tour à tour,
Miroir aérien, je reflète au passage
Les sourires changeants du jour.

Le soleil me rencontre au bout de sa carrière
Couché sur l'horizon dont j'enflamme le bord ;
Dans mes flancs transparents le roi de la lumière
Lance en fuyant ses flèches d'or.

Quand la lune, écartant son cortège d'étoiles,
Jette un regard pensif sur le monde endormi,
Devant son front glacé je fais courir mes voiles,
Ou je les soulève à demi.

On croirait voir au loin une flotte qui sombre,
Quand, d'un bond furieux fendant l'air ébranlé,
L'ouragan sur ma proue inaccessible et sombre
S'assied comme un pilote ailé.

Dans les champs de l'éther je livre des batailles ;
La ruine et la mort ne sont pour moi qu'un jeu.
Je me charge de grêle, et porte en mes entrailles
La foudre et ses hydres de feu.

Sur le sol altéré je m'épanche en ondées.
La terre rit ; je tiens sa vie entre mes mains.
C'est moi qui gonfle, au sein des terres fécondées,
L'épi qui nourrit les humains.

Où j'ai passé, soudain tout verdit, tout pullule ;
Le sillon que j'enivre enfante avec ardeur.
Je suis onde et je cours, je suis sève et circule,
Caché dans la source ou la fleur.

Un fleuve me recueille, il m'emporte, et je coule
Comme une veine au cœur des continents profonds.
Sur les longs pays plats ma nappe se déroule,
Ou s'engouffre à travers les monts.

Rien ne m'arrête plus ; dans mon élan rapide
J'obéis au courant, par le désir poussé,
Et je vole à mon but comme un grand trait liquide
Qu'un bras invisible a lancé.

Océan, ô mon père ! Ouvre ton sein, j'arrive !
Tes flots tumultueux m'ont déjà répondu ;
Ils accourent ; mon onde a reculé, craintive,
Devant leur accueil éperdu.

En ton lit mugissant ton amour nous rassemble.
Autour des noirs écueils ou sur le sable fin
Nous allons, confondus, recommencer ensemble
Nos fureurs et nos jeux sans fin.

Mais le soleil, baissant vers toi son œil splendide,
M'a découvert bientôt dans tes gouffres amers.
Son rayon tout puissant baise mon front limpide :
J'ai repris le chemin des airs !

Ainsi, jamais d'arrêt. L'immortelle matière
Un seul instant encor n'a pu se reposer.
La Nature ne fait, patiente ouvrière,
Que dissoudre et recomposer.

Tout se métamorphose entre ses mains actives ;
Partout le mouvement incessant et divers,
Dans le cercle éternel des formes fugitives,
Agitant l'immense univers.


Le nuage
Poèmes de Louise Ackermann

VIVE LA FRANCE, VIVE LA RÉPUBLIQUE ET VIVE LE PEUPLE....

RAPPORT SUR LES SENTIMENTS DU
CITOYEN TIGNARD YANIS
PAR
Y'BECCA

Lucila Godoy Alcayaga (7 April 1889 – 10 January 1957), known by her pseudonym Gabriela Mistral (Spanish: [ɡaˈβɾjela misˈtɾal]), was a Chilean poet-diplomat, educator and humanist. In 1945 she became the first Latin American author to receive a Nobel Prize in Literature, "for her lyric poetry which, inspired by powerful emotions, has made her name a symbol of the idealistic aspirations of the entire Latin American world". Some central themes in her poems are nature, betrayal, love, a mother's love, sorrow and recovery, travel, and Latin American identity as formed from a mixture of Native American and European influences. Her portrait also appears on the 5,000 Chilean peso bank note.

Born Lucila de María del Perpetuo Socorro Godoy Alcayaga
7 April 1889
Vicuña, Chile
Died 10 January 1957 (aged 67)
Hempstead, New York
Occupation Educator, Diplomat, Poet.
Nationality Chilean
Period 1914–1957
Notable awards Nobel Prize in Literature
1945
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Voir le profil de l'utilisateur http://www.atelier-yannistignard.com
 
The Rebel Fleet, Laniakea Supercluster et Gabriela Mistral.
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