sexta-feira, 20 de novembro de 2015

As Águas Estelares do Rio Eridanus nos revelando tesouros de Estrelas, Galáxias, Aglomerado, Void


Olá!

Eridanus, o Rio dos Céus Estrelados,
é realmente uma constelação de estrelas tímidas
e de desenho nem sempre muito fácil de ser delineado
- com exceções, é claro, para sua nascente, Cursa,
e para sua belíssima foz, Achernar!

No entanto, sempre em lugares de céus escuros e transparentes
e em noites sem Lua, as curvas desse Rio de Estrelas
 vão mostrando os caminhos celestes 
por onde vão passando suas águas estelares
 e desenhadas por estrelas tímidas
- sendo que uma delas, Epsilon Eridani parece acolher
um ainda não-confirmado exoplaneta.. 
que, mesmo não sendo confirmado
faz a festa em livros e filmes de ficcção científica
como também em games!

O interessante a bem percebermos, Caro Leitor,
é que esta constelação aparentemente escondida dos olhares
dos amantes das estrelas que moram em centros urbanos e iluminados,
se apresenta nos revelando tesouros inimagináveis!

São Galáxias maravilhosas fazendo parte
de Aglomerados que se confundem entre
as constelações de Eridanus e Fornax
(esta última inserida em uma das tantas curvas do Rio dos Céus Estrelados).

Existe um agrupamento em seus primeiros estágios de formação
entre o Aglomerado Fornax e o Grupo Eridanus
(o primeiro bem mais próximo a nós, 
enquanto o segundo é bem mais distante e espraiado)
 e ainda acolhendo o Grupo Dorado e outros,
constituindo o chamado Eridanus-Fornax-Dorado-Filamento
ou Superaglomerado Fornax ou ainda Superaglomerado do Sul.

Na maioria das vezes,
acontecem as denominações Fornax Supercluster e Fornax Void; 
porém a verdade é que na direção
onde as constelações Eridanus e Fornax se encontram, 
Aglomerados e Vazio acontecem.

Para ainda além, muito além,
Vamos encontrar um Void, um Vazio,
Considerado como um Imenso Vazio,
o Grande Vazio, The Great Void,
 talvez uma das maiores estruturas do universo visível
 – porém ainda não efetivamente confirmado.

Nesses tempos em que muitos dos rios da Terra estão secando...
ou mesmo em que o Rio Doce foi morto 
pela lama da ganância e do desrespeito do Poder
e tornou-se um rio literalmente amargo,
um Rio de Estrelas, Rio do Céu Estrelado, Eridanus,
permanece apresentando-se aos nossos olhos embevecidos
e voltados para buscar seus caminhos 
fazendo curvas através a abóbada celeste mais ao sul
e sempre em lugares de céus escuros e transparentes
e em noites de ausência de Lua.

Bom sabermos que o Rio dos Céus Estrelados, Eridanus,
permanece incólume em suas águas estelares....
......  Pelo menos nos céus, podemos confiar
que a ganância dos podres poderes não consegue alcançar.


Com um abraço estrelado,

Janine Milward

Stellarium



Eridanus

A selection of hand-colored engravings from Uranometria
Published:  Ausburg  1603
Dimensions:  Paper size app 15 1/2 x 12 inches



 Mario Jaci Monteiro - Cartas Celestes, as 88 Constelações


Mario Jaci Monteiro - As Constelações, Cartas Celestes
 - excerto apresentando ALFABETO GREGO, CONVENÇÕES E USO DA CARTA CELESTE











 ERIDANUS, O RIO ERIDANO



Posicionamento:
Ascensão Reta 1h22m / 5h9m      Declinação +0o.1 / -58o.1


Mito:
Esta constelação representa o Rio Padus ou onde Phaeton caiu quando degolado por Júpiter por causa de ter botado fogo no mundo ao mal-guiar o carro de seu pai, Phoebus.

Erídano é supostamente uma representação de equivalência celestial de um rio; é o Nilo para os Egípcios, e o Eufrates para os Babilônios.




Acessando
você encontrará Informações bem interessantes sobre o significado da nomeação Eridanus, suas principais Estrelas e excertos do texto de Richard H. Allen contando a História desta Constelação.



Fronteiras:
Eridanus faz fronteira com Horologium, Caelum, Lepus, Orion, Taurus, Cetus, Fornax, Pheonix e Hydra






"Achernar" by Fred the OysteriThe source code of this SVG is valid.This vector graphics image was created with Adobe Illustrator.. Licensed under GFDL via Commons - https://commons.wikimedia.org/wiki/File:Achernar.svg#/media/File:Achernar.svg



Achernar (α Eriα EridaniAlpha Eridani), sometimes spelled Achenar, is the brightest star in the constellation Eridanus and the tenth-brightest star in the night sky. Of the ten apparent brightest stars in the nighttime sky, Achernar is the hottest and bluest in color, being of spectral type B.[nb 1] Lying at the southern tip of Eridanus, the star has an unusually rapid rotational velocity, causing it to become oblate in shape. Achernar is actually a binary star system,[6] with the second star known as Achernar B. The second star is smaller and orbits Achernar A at a distance of roughly 12 astronomical units (AU). Achernar B is of spectral type A.






Stellarium 



Achernar.  Alpha Eridani. 
Ascensão Reta 01h37,0 - Declinação -57o 20
Magnitude visual 0,60 - Distância 118 anos-luz
Uma estrela branca situada na boca do Rio.  De Al Ahir al Nahr, o Fim do Rio. A Foz do Rio Erídano.
Esta é uma estrela tão ao sul que não faz parte da visão dos habitantes em latitudes bem ao norte.








Stellarium



Cursa - Beta Eridani
Magnitude visual 2.8 Distância 80 anos-luz,
Cadeira, vocábulo oriundo da expressão árabew Al Kursiyy Al Jauzah. 
 Esta estrela é o começo do Rio Erídano
 e encontra-se aos pés do Gigante Órion e sua estrela beta Rigel.









Stellarium


Acamar - Teta Eridani - Estrela Dupla
Ascensão Reta 02h57,5 - Declinação - 40o 23
Magnitude visual 3,42 e 4,5 - Distância 65 anos-luz
Distância entre estrelas 8”,15
A Lua.  
O Branco, nome de origem árabe que foi utilizado pela primeira vez nas Tabuas Alfonsinas. 
 Esta estrela já representou a Foz do Rio antes de a constelação ser estendida
 até alcançar a verdadeira Foz, Achernar.
É um sistema triplo sendo que o membro mais brilhante é visível a olho nu 
como uma anã amarela, 
sendo que suas duas companheiras são muito pálidas, 
uma das quais é uma anã vermelha e a outra, uma anã branca.


Alnahar - Delta Eridani
O Rio, nome de origem árabe.


Angetenar - Tau Eridani
O Meandro do Rio, proveniente da expressão árabe Al Hinayat al Nahr.


Azha - Eta Eridani
Ninho de Avestruz.


Beid ou Keid - Omicron Eridani
Ovo, do árabe Al Bais, o ovo do ninho de avestruz.  Nome árabe proveniente da expressão Al Kaid.


Theermin - Epsilon Eridani
Os Gêmeos, nome oriundo do árabe Al Tauaman.


Zaurak - Gamma Eridani
Barco, oriundo do árabe Al Nair Al Zaurak, ou seja, a brilhante estrela do barco.




6a. Edição do Atlas Celeste
de autoria de Ronaldo Rogério de Freitas Mourão,
Editora Vozes, Petrópolis, ano de 1986





Stellarium



Epsilon Eridani é uma estrela da sequência principal do K2 classe espectral. Apenas 10,5 anos-luz de distância, é a estrela mais próxima da constelação Eridanus, bem como o terceiro sistema estelar mais próximo visível a olho nu. Sua idade é estimada em menos de um bilhão de anos. Devido à sua relativa juventude, Epsilon Eridani tem um maior nível de atividade magnética do que o Sol, com um vento estelar 30 vezes mais forte. Seu período de rotação é relativamente rápida 11,2 dias, embora isso varie de acordo com a latitude. Epsilon Eridani é menor e menos maciça que o Sol, com um menor enriquecimento de elementos além de hidrogênio e hélio.

https://pt.wikipedia.org/wiki/Epsilon_Eridani




Epsilon Eridani b, com freqüência catalogada como HD 22049 b, é um planeta extrasolar descoberto em 7 de agosto de 2000. Dista aproximadamente a 10anos luz do planeta Terra, na constelação de Eridanus. Orbita a estrela Epsilon Eridani, convertendo-o no sistema planetario conhecido mais próximo ao Sistema Solar.


HD 22049 b
ExoplanetaLista de exoplanetas
Estrela mãe
EstrelaEpsilon Eridani
ConstelaçãoEridanus
Ascensão reta3h 32m 55.8442s
Declinação-9° 27′ 29.744″
Distância10.5 ± 0.03 anos-luz
3.218 ± 0.009 pc
Elementos orbitais
Características físicas
Descoberta
Data da descoberta7 de agosto de 2000
Método de detecçãoEspectroscopia Doppler
Outras designações
18 Eridani b, Gliese 144 b, HD 22049 b, HIP 16537 b, HR 1084 b





Epsilon Eridani (ε Eriε Eridani) is a star in the southern constellation Eridanus, along a declination 9.46° south of the celestial equator. This allows it to be viewed from most of Earth's surface. At a distance of 10.5 light years (ly), it has an apparent magnitude of 3.73. It is the third closest individual star or star system visible to the unaided eye and was the closest star known to host a planet until the unconfirmed discovery of Alpha Centauri Bb. Its age is estimated at less than a billion years. Because of its youth, Epsilon Eridani has a higher level of magnetic activity than the present-day Sun, with a stellar wind 30 times as strong. Its rotation period is 11.2 days at the equator. Epsilon Eridani is smaller and less massive than the Sun, and has a comparatively lower level of elements heavier than helium.[18] It is a main-sequence star of spectral class K2, which means that energy generated at the core through nuclear fusion of hydrogen is emitted from the surface at a temperature of about 5,000 K, giving it an orange hue.
The motion of Epsilon Eridani along the line of sight to Earth, known as the radial velocity, has been regularly observed for more than twenty years. Periodic changes in this data yielded evidence of a giant planet orbiting Epsilon Eridani, making it one of the nearest extrasolar systems with a candidate exoplanet.[19] This object, Epsilon Eridani b, was formally announced in 2000 by a team of astronomers led by Artie Hatzes.[19] Current data indicate that this planet orbits with a period of about 7 years at a mean separation of 3.4 astronomical units (AU), where 1 AU is the mean distance between Earth and the Sun.[20] Although this discovery has been controversial because of the amount of background noise in the radial velocity data,[21] many astronomers now regard the planet as confirmed.
The system includes two belts of rocky asteroids: one at about 3 AU and a second at about 20 AU, whose structure may be maintained by a hypothetical second planet, Epsilon Eridani c.[22] Epsilon Eridani harbors an extensive outer debris disk of remnant planetesimals left over from the system's formation.[23]

Epsilon Eridani's designation was established in 1603 by Johann Bayer. It may be a member of the Ursa Major Moving Group of stars that share a similar motion through the Milky Way, implying these stars shared a common origin in an open cluster. Its nearest neighbor, the binary star system Luyten 726-8, will have a close encounter with Epsilon Eridani in approximately 31,500 years when they will be separated by about 0.93 ly.[24] As one of the nearest Sun-like stars with the potential for a planet that may harbor life,[25] Epsilon Eridani has been the target of SETI searches. Epsilon Eridani appears in science fiction stories and has been suggested as a destination for interstellar travel.[26] From Epsilon Eridani, the Sun would appear as a 2.4-magnitude star in Serpens.[note 1]

Epsilon Eridani b is an unconfirmed extrasolar planet approximately 10 light-years away orbiting the star Epsilon Eridani, in the constellation of Eridanus (theRiver).

The planet and its host star is one of the planetary systems selected by the International Astronomical Union as part of their public process for giving proper names to exoplanets and their host star (where no proper name already exists).[1][2] The process involves public nomination and voting for the new names, and the IAU plans to announce the new names in mid-November 2015.[3]



Hubble Observations Confirm that Planets Form from Disks Around Stars




Image Type: Artwork
Credit: NASAESA, and G. Bacon (STScI)
This is an artist's concept of a Jupiter-mass planet orbiting the nearby star Epsilon Eridani. Located 10.5 light-years away, it is the closest known exoplanet to our solar system. The planet is in an elliptical orbit that carries it as close to the star as Earth is from the Sun, and as far from the star as Jupiter is from the Sun.
Epsilon Eridandi is a young star, only 800 million years old. It is still surrounded by a disk of dust that extends 20 billion miles from the star. The disk appears as a linear sheet of reflecting dust in this view because it is seen edge-on from the planet's orbit, which is in the same plane as the dust disk.



This artist's conception shows the closest known planetary system to our own, called Epsilon Eridani. Observations from NASA's Spitzer Space Telescope show that the system hosts two asteroid belts, in addition to previously identified candidate planets and an outer comet ring.
Epsilon Eridani is located about 10 light-years away in the constellation Eridanus. It is visible in the night skies with the naked eye.
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Young Solar System in the Making




This artist's diagram compares the Epsilon Eridani system to our own solar system. The two systems are structured similarly, and both host asteroids (brown), comets (blue) and planets (white dots).
Epsilon Eridani is our closest known planetary system, located about 10 light-years away in the constellation Eridanus. Its central star is a younger, fainter version of our sun, and is about 800 million years old—about the same age of our solar system when life first took root on Earth.
Observations from NASA's Spitzer Space Telescope show that the system hosts two asteroid belts, in addition to previously identified candidate planets and an outer comet ring.









Johann Bayer — Eridanus
Eridanus




Programa Stellarium





VEJA QUE A PEQUENA CONSTELAÇÃO FORNAX, A FORNALHA, 
ACONTECE INSERIDA EM UMA DAS TANTAS CURVAS DO RIO ERIDANUS
e veja que Achernar, estrela-alpha Eridanii, situa-se bem próxima ao Peixe DORADO.

Estas duas constelações vêm sendo sempre muito comentadas porquanto acolhem Aglomerados e Void, Vazio.

Na maioria das vezes, acontece a denominação Fornax Supercluster e Fornax Void porém a verdade é que na direção onde as constelações Eridanus e Fornax se encontram, Aglomerados e Vazio acontecem.


File:2MASS LSS chart-NEW Nasa.jpg
AuthorIPAC/Caltech, by Thomas Jarrett
Panoramic view of the entire near-infrared sky reveals the distribution of galaxies beyond the Milky Way. The image is derived from the 2MASS Extended Source Catalog (XSC)—more than 1.5 million galaxies, and the Point Source Catalog (PSC)--nearly 0.5 billion Milky Way stars

The Fornax and Eridanus Clusters

The Fornax and Eridanus clusters are two very famous clusters in the southern hemisphere. Although they look near to each other, they are separated by about 20 million light years. The nearer Fornax cluster is about 65 million light years from us, and the Eridanus cluster is about 85 million light years from us. There are many other groups of galaxies scattered around these two clusters and collectively these groups are often called the Fornax Supercluster or Southern Supercluster.y famous clusters in the southern hemisphere. Although they look near to each other, they are separated by about 20 million light years. The nearer Fornax cluster is about 65 million light years from us, and the Eridanus cluster is about 85 million light years from us. 





The Fornax and Eridanus Clusters


The Eridanus Cluster

This is a map of the Eridanus Cluster. This cluster is less spectacular than the Fornax cluster, partly because the galaxies are spread across a larger area and partly because the cluster is rather further and hence dimmer than the Fornax cluster. The Eridanus cluster is roughly split into two halves: a northern subgroup around NGC 1407 and a southern subgroup around NGC 1395.





The Eridanus Cluster


Properties of the Eridanus Cluster
Equatorial CoordinatesRA=03h35m Dec=-22°
Galactic Coordinatesl=214° b=-53°
Supergalactic CoordinatesL=281° B=-43°
Distance to the centre of the cluster85 million light years
Number of large galaxies in the cluster73
Alternative names for the clusterFornax II cluster




The center of the Eridanus Cluster is roughly 23 Mpc (75 Mly) from Earth, and contains about 73 main galaxies and about 200 total galaxies. About 30% have Hubble classifications of elliptical or S0 and the remaining 70% are spiral or irregular.[2] These galaxies reside in smaller groups which are all loosely gravitationally bound to each other, suggesting that the system is still condensing from the Hubble flow and may eventually form a cluster of about 1014 M. A low velocity dispersion compared to that of, for example, the Coma cluster, supports this hypothesis.[3] The Eridanus Cluster is located in the constellation Eridanus near the Fornax Cluster, and is sometimes called the "Fornax II Cluster".[4]


Eridanus Cluster
Observation data (Epoch J2000)
Constellation(s)Eridanus
Right ascension03h 28m 13.8s[1]
Declination−20° 44′ 40″[1]
Brightest memberNGC 1232 (B)
Number of galaxies~200[2]
Velocity dispersion261 km/s[3]
Redshift0.005570[1]
Distance
(co-moving)
23 Mpc (75 Mly)[1]
ICM temperature~107 K (~1 keV)[2]
Binding mass~1014 M[3]
X-ray flux0.105 mCrab[2]
Other designations
Fornax II Cluster,[4] de Vaucouleurs Group 31[5

Table of galaxies[edit]

Column 1: Name of the galaxy

Column 2: Right ascension for epoch J2000

Column 3: Declination for epoch J2000

Column 4: Blue apparent magnitude of the galaxy

Column 5: Galaxy type: E=Elliptical; S0=Lenticular; Sa, Sb, Sc, Sd=Spiral; SBa, SBb, SBc, SBd=Barred Spiral; Sm, SBm, Irr=Irregular

Column 6: Angular diameter of the galaxy (arcminutes)

Column 7: Diameter of the galaxy (thousands of light years)

Column 8: Recessional velocity (km/s) of the galaxy relative to the cosmic microwave background



NameRA equatorial
coordinates
Dec equatorial
coordinates
Blue
Mag
TypeSize
(arcmin)
Size
(kly)
RV
(km/s)
ESO 547-0903 06.0-19 2316.8Irr1.3351509
ESO 547-1203 09.6-17 5016.5Scd1.5351837
NGC 123203 09.8-20 3510.7SBc6.91701517
IC 189803 10.3-22 2413.7SBc3.4851164
ESO 547-2003 13.0-17 5616.0SBm1.2301825
NGC 125803 14.1-21 4613.9SBc1.3301340
NGC 129703 19.2-19 0613.5E2.0501395
NGC 130003 19.7-19 2511.2SBbc6.01501421
NGC 131503 23.1-21 2314.0S01.5351534
PGC 1268003 23.4-19 17 ?Irr1.3301400
ESO 548-0503 23.8-19 4514.7SBm1.5351690
NGC 132503 24.4-21 3312.3SBbc4.71151446
NGC 1325A03 24.8-21 2013.6SBcd1.8451188
ESO 548-1603 26.0-21 2015.6Scd1.7401977
NGC 133203 26.3-21 2011.4E4.21051383
ESO 548-2103 27.6-21 1414.7SBd2.0501541
ESO 548-2503 29.0-22 0915.0SBa1.3301542
NGC 134503 29.5-17 4714.3SBc1.4351385
ESO 481-3003 29.6-23 2115.5Scd1.5351504
NGC 134703 29.7-22 1713.9SBc1.4351624
ESO 548-2803 30.6-17 5614.0S01.3351360
ESO 548-2903 30.8-21 0314.3SBbc1.1301175
NGC 135303 32.1-20 4912.4SBb3.5851390
ESO 548-3203 32.3-17 4315.8SBm1.6401815
ESO 548-3303 32.5-18 5714.5S01.3351552
ESO 548-3403 33.0-21 0514.6SBc1.1301610
ESO 482-0503 33.0-24 0815.2SBcd2.1501783
IC 195203 33.4-23 4313.5SBbc2.5601683
IC 195303 33.7-21 2912.7SBc2.6651733
NGC 135903 33.8-19 2913.0SBm2.1551833
NGC 136203 33.9-20 1714.2S01.2301085
ESO 548-4403 34.3-19 2514.2S01.3351561
ESO 548-4703 34.7-19 0214.1S02.5601472
NGC 137103 35.0-24 5611.6SBa5.61401344
NGC 137003 35.2-20 2213.9E1.535933
IC 196203 35.6-21 1814.8SBd2.5601670
ESO 482-1103 36.3-25 3614.7Sbc1.4351469
NGC 137703 36.7-20 5413.8S01.7451645
NGC 138503 37.5-24 3011.5SBc3.7901373
NGC 138303 37.7-18 2013.8S01.7401828
ESO 482-1703 37.7-22 5514.9Sab1.3301330
NGC 139003 37.9-19 0014.9SBa1.3351078
NGC 139503 38.5-23 0210.7E5.61401577
NGC 139803 38.9-26 2010.5SBab7.11751289
NGC 140303 39.2-22 2314.1E1.3301751
NGC 140103 39.4-22 4313.7S01.9501406
NGC 140003 39.5-18 4112.3E2.360415
ESO 548-6303 39.6-20 0115.1Sbc1.4351846
ESO 548-6503 40.0-19 2215.3Sa1.4351102
IC 34303 40.1-18 2714.3S01.4351730
NGC 140703 40.2-18 3510.9E5.11251650
ESO 548-6803 40.3-18 5614.3E1.3351636
NGC 141203 40.5-26 5214.7S01.4351675
ESO 548-7003 40.7-22 1715.4SBcd1.6401615
ESO 482-3203 40.7-26 4715.9Irr1.2301621
NGC 141503 40.9-22 3412.8Sa3.3801451
NGC 141403 41.0-21 4314.6SBbc1.6401464
ESO 482-3503 41.2-23 5014.2SBab1.8451756
NGC 142203 41.5-21 4114.2SBab2.3551514
IC 34603 41.7-18 1613.9S01.9451830
ESO 548-7903 41.9-18 5414.8Sa1.1301914
ESO 548-8203 42.7-17 3015.4Sbc1.1301590
NGC 142603 42.8-22 0612.7E2.5601296
ESO 549-0203 43.0-19 0114.9SBm1.330988
ESO 549-0603 43.6-21 1415.7Irr1.3301490
NGC 143903 44.8-21 5512.4E2.6651577
NGC 144003 45.0-18 1612.9S02.2551403
NGC 143803 45.3-23 0013.3SBa2.0501438
NGC 145203 45.4-18 3812.9Sa2.3601619
ESO 549-1803 48.2-21 2813.3SBc2.5601473
ESO 482-4603 49.7-27 0013.7Sc3.5901422
ESO 482-4903 52.4-23 0315.3Sc1.1301377
NGC 148203 54.6-20 3013.3S02.2551753








http://www.whillyard.com. 

Fornax Cluster & 
Eridanus Group
The Fornax Cluster is a small cluster of about 58 galaxies, much smaller than the Virgo Cluster, for example, located around 20 Mpc away.  It contains two massive galaxies - NGC 1316, a lenticular, and NGC 1365, a barred spiral.  Both are more than twice the diameter of the Milky Way.  There is substantial evidence that one, or maybe  two, sub-groups of galaxies have collided with the main group in the astronomically recent past.  Associated with the Fornax Cluster, the Eridanus Group lies about 7 Mpc further away.  It contains around 200 galaxies, is approximately 10 Mpc across, and about 23 Mpc away.  This grouping is in the early stages of formation, and with the Fornax cluster, the Dorado group and others, forms the Eridanus-Fornax-Dorado Filament.  It is very interesting because although many of its constituent galaxies are quite old, the group itself is rather young and still forming.  It also has a large number of lenticular (type S0) galaxies.  These are believed to be part of the evolution of spiral galaxies again implying great age for many of the galaxies. 
LEIA MAIS EM





A 12th-magnitude spiral galaxy (type SAB(rs)b) in Eridanus (RA 03 41 57.2, Dec -04 42 19)

Apparent size 2.3 by 1.2 arcmin.


Above, a 2.4 arcmin wide closeup of NGC 1417

Below, a 12 arcmin wide region centered on the galaxy, also showing NGC 1418








NGC 1232 é uma galáxia espiral localizada a cerca de setenta e dois milhões de anos-luz (aproximadamente 22,07megaparsecs) de distância na direção da constelação de Erídano. Possui uma magnitude aparente de 9,8, uma declinação de -20º 34' 45" e uma ascensão reta de 03 horas, 09 minutos e 45,1 segundos.e tem cerca de 200 mil anos luzes de diâmetro






NGC 1232: Dwarf Galaxy Caught Ramming Into a Large Spiral

X-ray: NASA/CXC/Huntingdon Inst. for X-ray Astronomy/G.Garmire, Optical: ESO/VLT



Composite

NGC 1232
Optical
NGC 1232
Xray

  • Observations with Chandra have revealed a giant cloud of superheated gas in a galaxy about 60 million light years from Earth.

  • Because this gas is about 6 million degrees, it only glows in X-ray light.

  • A collision between a dwarf galaxy and a much larger galaxy called NGC 1232 is the likely cause of this gas cloud.

  • A new composite of X-rays (purple) from Chandra and optical data (blue and white) shows the scene of the collision.

Observations with NASA's Chandra X-ray Observatory have revealed a massive cloud of multimillion-degree gas in a galaxy about 60 million light years from Earth. The hot gas cloud is likely caused by a collision between a dwarf galaxy and a much larger galaxy called NGC 1232. If confirmed, this discovery would mark the first time such a collision has been detected only in X-rays, and could have implications for understanding how galaxies grow through similar collisions.
LEIA MAIS EM 









A Blue Whirlpool in The River

A new image taken with ESO’s Very Large Telescope shows the galaxy NGC 1187. This impressive spiral lies about 60 million light-years away in the constellation of Eridanus (The River). NGC 1187 has hosted two supernova explosions during the last thirty years, the latest one in 2007. This picture of the galaxy is the most detailed ever taken.


Videos

Zooming in on the spiral galaxy NGC 1187
Zooming in on the spiral galaxy NGC 1187
Panning across a new VLT image of the spiral galaxy NGC 1187
Panning across a new VLT image of the spiral galaxy NGC 1187

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This chart shows the location of NGC 1187 in the constellation of Eridanus (The River). This map shows most of the stars visible to the unaided eye under good conditions, and NGC 1187 itself is highlighted with a red circle on the image. This galaxy appears as a faint smudge through medium-sized amateur telescopes under good conditions.
Credit:
ESO, IAU and Sky & Telescope








Title: Orion and Haase (Lepus the Rabbit)
Map Maker: Johann Ehlert Bode


IC 2118 (also known as Witch Head Nebula due to its shape), is an extremely faint reflection nebula believed to be an ancient supernova remnant or gas cloud illuminated by nearby supergiant star Rigel in Orion. It lies in the Eridanusconstellation, about 900 light-years from Earth. The nature of the dust particles, reflecting blue light better than red, is a factor in giving the Witch Head its blue color. Radio observations show substantial carbon monoxide emission throughout parts of IC 2118 an indicator of the presence of molecular clouds and star formation in the nebula. In fact candidates for pre-main sequence stars and some classic T-Tauri stars have been found deep within the nebula.[1]
The molecular clouds of IC 2118 are probably juxtaposed to the outer boundaries of the vast Orion-Eridanus bubble, a giant supershell of molecular hydrogen blown by the high mass stars of the Orion OB1 association. As the supershell expands into the interstellar medium, favorable circumstances for star formation occur. IC 2118 is located in one such area.The wind blown appearance and cometary shape of the bright reflection nebula is highly suggestive of a strong association with the high mass luminous stars of Orion OB1. The fact that the heads of the cometary clouds of IC2118 point northeast towards the association is strong support of that relationship.

The Witch Head Nebula 
Credit: Gary Stevens
TypeReflection
Right ascension05h 02m 00.00s
Declination-07° 54′ 00.0"
Distance1,000 ly
Apparent magnitude(V)13
Apparent dimensions (V)3 × 1 °
ConstellationEridanus



Baby Stars Brewing in the Witch Head Nebula

Eight hundred light-years away in the Orion constellation, a gigantic murky cloud called the "Witch Head Nebula" is teeming with dust-obscured newborn stars waiting to be uncovered. In this image, the super sensitive infrared eyes of NASA's Spitzer Space Telescope reveal 12 new baby stars in a small portion of the cloud commonly referred to as the Witch Head's "pointy chin."







NGC 1132 é uma galáxia elíptica (E) localizada na direcção da constelação de Eridanus. Possui uma declinação de -01° 16' 28" e uma ascensão recta de 2 horas, 52 minutos e 51,8 segundos.

A galáxia NGC 1132 foi descoberta em 23 de Novembro de 1827 por John Herschel.
NGC 1132: A Mysterious Elliptical Galaxy



NGC 1132
Credit X-ray: NASA/CXC/Penn State/G. Garmire; Optical: NASA/ESA/STScI/M. West
This image of the elliptical galaxy NGC 1132 and its surrounding region combines data from NASA's Chandra X-ray Observatory and the Hubble Space Telescope. The blue/purple in the image is the X-ray glow from hot, diffuse gas detected by Chandra. Hubble's data reveal a giant foreground elliptical galaxy, plus numerous dwarf galaxies in its neighborhood, and many much more distant galaxies in the background.
Astronomers have dubbed NGC 1132 a "fossil group" because it contains an enormous amount of dark matter, comparable to the dark matter found in an entire group of galaxies. Also, the large amount of hot gas detected by Chandra is usually found for groups of galaxies, rather than a single galaxy.




Hubble Optical Image of NGC 1132 

The elliptical galaxy NGC 1132 reveals the final result of what may have been a group of galaxies that merged together in the recent past. Another possibility is that the galaxy formed in isolation as a "lone wolf" in a universe ablaze with galaxy groups and clusters. This image of NGC 1132 was taken with Hubble's Advanced Camera for Surveys. Data obtained in 2005 and 2006 through green and near-infrared filters were used in the composite. NGC 1132 is located approximately 318 million light-years away in the constellation Eridanus, the River. More information at Hubble
(Credit: Optical: NASA/ESA/STScI/M. West)



Chandra X-ray Image of NGC 1132 

This image of elliptical galaxy NGC 1132 and its surrounding region shows the X-ray glow from hot, diffuse gas detected by Chandra. Astronomers have dubbed NGC 1132 a "fossil group" because it contains an enormous amount of dark matter, comparable to the dark matter found in an entire group of galaxies. Also, the large amount of hot gas detected by Chandra is usually found for groups of galaxies, rather than a single galaxy. On the right, the white box represents the Hubble Space Telescope's field of view.
(Credit: X-ray:NASA/CXC/Penn State/G. Garmire)





NGC 1700 é uma galáxia elíptica (E4) localizada na direcção da constelação de Eridanus. Possui uma declinação de -04° 51' 55" e uma ascensão recta de 4 horas, 56 minutos e 56,2 segundos.
A galáxia NGC 1700 foi descoberta em 5 de Outubro de 1785 por William Herschel.

NGC 1700:
Giant X-Ray Disk Sheds Light On Galactic Merger 



Credit: NASA/Ohio U./T.Statler et al.
The Chandra image of the elliptical galaxy NGC 1700 shows a flattened oval of multi-million degree gas, supporting the idea that it is the result of a merger of two smaller galaxies about 3 billion years ago.




(Credit: NASA/Ohio U./

T.Statler et al.)
.........another version of the Chandra image shows only the low-energy X-rays and reveals a giant inner disk. This disk of 6-million degree gas appears light blue in the multicolor image above.







NGC 1309 é uma galáxia espiral localizada a cerca de cem milhões de anos-luz de distância na direção da constelação de Erídano. Possui uma magnitude aparente de 11,5, uma declinação de -15º 24' 02" e uma ascensão reta de 3 horas, 22minutos e 6,5 segundos.





Hubble Snaps Images of a Pinwheel-Shaped Galaxy

Credit: NASAESA, The Hubble Heritage Team, (STScI/AURA) and A. Riess (STScI)
Looking like a child's pinwheel ready to be set a spinning by a gentle breeze, this dramatic spiral galaxy is one of the latest viewed by NASA's Hubble Space Telescope. Stunning details of the face-on spiral galaxy, cataloged as NGC 1309, are captured in this color image.
Recent observations of the galaxy taken in visible and infrared light come together in a colorful depiction of many of the galaxy's features. Bright blue areas of star formation pepper the spiral arms, while ruddy dust lanes follow the spiral structure into a yellowish central nucleus of older-population stars. The image is complemented by myriad far-off background galaxies.
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Lick Observatory Ground-Based Image of SN2002fk in NGC 1309

SN2002fk as observed from Lick Observatory Kait 0.76 meter telescope in 2002. The location of the supernova is marked on the 2005 Hubble ACS image.
Credit for Lick Observatory Image: W. Li and A. V. Filippenko (University of California, Berkeley)
Credit for HST Image: NASAESA, The Hubble Heritage Team (STScI/AURA), and A. Riess (STScI)




NGC 1614 é uma galáxia espiral barrada (SBc/P) localizada na direcção da constelação de Eridanus. Possui uma declinação de -08° 34' 45" e uma ascensão recta de 4 horas, 33 minutos e 59,8 segundos.

A galáxia NGC 1614 foi descoberta em 29 de Dezembro de 1885 por Lewis A. Swift.


Hubble Interacting Galaxy NGC 1614

Object Names: NGC 1614, Arp 186, Mrk 0617, II Zw 015
Image Type: Astronomical
Credit: NASAESA, the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration, and A. Evans (University of Virginia, Charlottesville/NRAO/Stony Brook University)
The galaxy system NGC 1614 has a bright optical center and two clear inner spiral arms that are fairly symmetrical. It also has a spectacular outer structure that consists principally of a large one-sided curved extension of one of these arms to the lower right, and a long, almost straight tail that emerges from the nucleus and crosses the extended arm to the upper right. 
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NGC 1531 é uma galáxia elíptica (E-S0) localizada na direcção da constelação de Eridanus. Possui uma declinação de -32° 51' 03" e uma ascensão recta de 4 horas, 11 minutos e 59,1 segundos.

A galáxia NGC 1531 foi descoberta em 19 de Outubro de 1835 por John Herschel.

NGC 1532 é uma galáxia espiral barrada (SBb) localizada na direcção da constelação de Eridanus. Possui uma declinação de -32° 52' 23" e uma ascensão recta de 4 horas, 12 minutos e 03,8 segundos.
A galáxia NGC 1532 foi descoberta em 29 de Outubro de 1826 por James Dunlop.

Ballet of Interacting Galaxies

Ficheiro:ESO - Ngc1532 gendler (by).jpg
This photograph was produced by European Southern Observatory (ESO).
ESO/IDA/Danish 1.5 m/R.Gendler and J.-E. Ovaldsen
The pair of galaxies NGC 1531/2, engaged in a spirited waltz, is located about 70 million light-years away towards the southern constellation Eridanus (The River). The deformed foreground spiral galaxy laced with dust lanes NGC 1532 is so close to its companion — the background galaxy with a bright core just above the centre of NGC 1532 — that it gets distorted: one of its spiral arms is warped and plumes of dust and gas are visible above its disc. The cosmic dance leads to another dramatic effect: a whole new generation of massive stars were born in NGC 1532 because of the interaction. They are visible as the purple objects in the spiral arms.
This exquisite image was made using the 1.5-metre Danish telescope at the ESO La Silla Observatory, Chile. It is based on data obtained through three different filters: B, V and R. The field of view is 12 x 12 arcmin.





NGC 1518 é uma galáxia espiral barrada (SBd) localizada na direcção da constelação de Eridanus. Possui uma declinação de -21° 10' 46" e uma ascensão recta de 4 horas, 06 minutos e 49,0 segundos.
A galáxia NGC 1518 foi descoberta em 13 de Novembro de 1835 por John Herschel.




A 12th-magnitude spiral galaxy (type SB(s)dm) in Eridanus (RA 04 06 49.0, Dec -21 10 46)
The second IC notes (per Howe) "Minute of RA is 00, not 01". Based on a recessional velocity of 920 km/sec, NGC 1517 is about 40 million light years away, in reasonable agreement with redshift-independent distance estimates of 25 to 40 million light years. Given that and its apparent size of 2.9 by 1.4 arcmin, it is about 35 thousand light years across.
Above, a 3.6 arcin wide closeup of NGC 1518
Below, a detailed view of the northern half of the galaxy (Image Credits: Hubble Legacy Archive)
Below, a 12 arcmin wide region centered on the galaxy




NGC 1535 - Eridanus  - Nebulosa Nebulosa Planetária
Ascensão Reta  04h13m      Declinação -12o.48
Tipo Nebulosa Planetária NP         Dimensão 0,5        Magnitude 17
Magnitude da Estrela associada   12        


NGC 1535 é uma nebulosa planetária na direção da constelação de Eridanus. O objeto foi descoberto pelo astrônomo William Herschel em 1785, usando um telescópio refletor com abertura de 18,6 polegadas. Devido a sua moderada magnitude aparente(+9,6), é visível apenas com telescópios amadores ou com equipamentos superiores.








NGC 1234 is barred spiral galaxy in the constellation Eridanus, discovered by Francis Preserved Leavenworth in 1886.
Its apparent magnitude is 14.2
File:NGC 1234 GALEX WikiSky.jpg

Authoren:NASAen:WikiSky
Permission
PD-NASA







NGC 1300 is a barred spiral galaxy about 61 million light-years away in the constellation Eridanus. The galaxy is about 110,000 light-years across; just slightly larger than our own galaxy, the Milky Way. It is a member of theEridanus Cluster, a cluster of 200 galaxies.[3][4] It was discovered by John Frederick William Herschel in 1835.[citation needed]






File:Hubble2005-01-barred-spiral-galaxy-NGC1300.jpg

Source
AuthorNASA, ESA, and The Hubble Heritage Team STScI/AURA)

At Hubble's resolution, a myriad of fine details, some of which have never before been seen, is seen throughout the galaxy's arms, disk, bulge, and nucleus. Blue and red supergiant stars, star clusters, and star-forming regions are well resolved across the spiral arms, and dust lanes trace out fine structures in the disk and bar. Numerous more distant galaxies are visible in the background, and are seen even through the densest regions of NGC 1300


Credit: NASAESA, and The Hubble Heritage Team (STScI/AURA)
Acknowledgment: P. Knezek (WIYN)




Giant Radio Jet Coming from Wrong Kind of Galaxy

Credit: NASA, W. Keel (University of Alabama), M. Ledlow (Gemini Observatory), F. Owen (NRAO) and AUI/NSF








Jurassic Space: Ancient Galaxies Come Together After Billions of Years

Object Name: HCG 31
Image Type: Astronomical
Credit: NASAESA, S. Gallagher (The University of Western Ontario), and J. English (University of Manitoba)
These four dwarf galaxies waited billions of years to come together, setting off a fireworks show as thousands of new star clusters come to life. The distorted galaxies are quickly producing massive, hot, young stars that are pumping out ultraviolet radiation, heating up surrounding gas clouds, and causing them to glow.
Such encounters between dwarf galaxies are normally seen billions of light-years away and therefore occurred billions of years ago. But these galaxies, members of Hickson Compact Group 31, are relatively nearby, only 166 million light-years away.






A members-only galaxy club



This new Hubble image shows a handful of galaxies in the constellation of Eridanus (The River). NGC 1190, shown here on the right of the frame, stands apart from the rest; it belong to an exclusive club known as Hickson Compact Group 22 (HCG 22).
There are four other members of this group, all of which lie out of frame: NGC 1189, NGC 1191, NGC 1192, and NGC 1199. The other galaxies shown here are nearby galaxies 2MASS J03032308-1539079 (centre), and dCAZ94 HCG 22-21 (left), both of which are not part of HCG 22.
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NGC 1190 é uma galáxia lenticular (S0) localizada na direcção da constelação de Eridanus. Possui uma declinação de -15° 39' 44" e uma ascensão recta de 3 horas, 03 minutos e 26,0 segundos.
A galáxia NGC 1190 foi descoberta em 1886 por Frank Leavenworth.




The spiral galaxy NGC 1345 and its loose and ragged arms dominate this rich image from the NASA/ESA Hubble Space Telescope. It is a member of the Eridanus Galaxy Cluster — a group of about 70 galaxies that lies 85 million light-years away in the constellation of Eridanus (the River). This region of the night sky is well populated with bright galaxies, with the Fornax Cluster of galaxies also nearby on the celestial sphere, although the two clusters are actually separated by about 20 million light-years. Collectively, they are known as the Fornax Supercluster or the Southern Supercluster.
John Herschel discovered NGC 1345 in 1835 from South Africa. He described it as small and very faint and it is still far from easy to see it even with quite a large amateur telescope, where it appears as a small, circular fuzz.

NGC 1345 é uma galáxia {{{typ}}} localizada na direcção da constelação de Eridanus. Possui uma declinação de -17° 46' 45" e uma ascensão recta de 3 horas, 29 minutos e 31,5 segundos.
A galáxia NGC 1345 foi descoberta em 11 de Dezembro de 1835 por John Herschel.





NASA Telescopes Help Discover Surprisingly Young Galaxy

Object Name: Abell 383
Image Type: Astronomical
Credit: NASAESA, J. Richard (Center for Astronomical Research/Observatory of Lyon, France), and J.-P. Kneib (Astrophysical Laboratory of Marseille, France)
Acknowledgment: M. Postman (STScI)

Astronomers have uncovered one of the youngest galaxies in the distant universe, with stars that formed 13.5 billion years ago, a mere 200 million years after the Big Bang. The finding addresses questions about when the first galaxies arose, and how the early universe evolved.
NASA's Hubble Space Telescope was the first to spot the newfound galaxy. Detailed observations from the W.M. Keck Observatory on Mauna Kea in Hawaii revealed the observed light dates to when the universe was only 950 million years old; the universe formed about 13.7 billion years ago.

Lensing Galaxy Cluster Abell 383 (Annotated)






Abell 383: Getting a Full Picture of an Elusive Subject


Abell 383
Optical Image
Composite
Abell 383
X-Ray

X-ray: NASA/CXC/Caltech/A.Newman et al/Tel Aviv/A.Morandi & M.Limousin; Optical: NASA/STScI, ESO/VLT, SDSS
Two teams of astronomers have used data from NASA's Chandra X-ray Observatory and other telescopes to map the distribution of dark matter in a galaxy cluster known as Abell 383, which is located about 2.3 billion light years from Earth.








Abell 521: A Galaxy Cluster Mash-up



Abell 521


X-ray (NASA/CXC/INAF/G.Brunetti et al.); Radio (NRAO/NSF/INAF/G.Brunetti et al.)

This composite image shows the galaxy cluster Abell 521, located about 2.9 billion light years from Earth.

Chandra X-ray Image
of Abell 521







O TEXTO ABAIXO É DE UMA SIMPLICIDADE ÍMPAR, 
a meu ver, 
NA EXPLICAÇÃO SOBRE AS ESTRUTURAS DO UNIVERSO.

A síntese e a tradução livre e literal foi realizada por mim, Janine.


Direitos autorais    © 2013 A AstroGnom.

Ein ‘Dankeschön’ an Chris Hadfield – Agradecimento a Chris Hadfield

Was ist ein “Void”? Die Strukturen des Universums

What is a "Void"? The 
structures of the universe




Síntese e tradução livre e literal realizada a partir da versão inglesa por Janine Milward

O que é um “Void”?  As Estruturas do Universo

....................................................
É preciso que saibamos que nosso universo não é sem-estrutura. Mesmo em escalas imensas, uma estrutura pode ser encontrada.  Para melhor compreendermos essa realidade, temos que fazer uma enorme viagem.
Ao fazermos um ZOOM a partir da Terra e em direção à imensidão do universo, estaremos primeiramente encontrando 7 planetas que, juntamente com nossa Terra, se movimentam em torno de uma estrela, o Sol.  Planetas e Sol formam o Sistema Solar. 
Quando o zoom se amplia, descobrimos muitas estrelas, outros sistemas solares.  Estes sistemas solares vivenciam em conjunto uma estrutura chamada Galáxia.  Nossa Galáxia é conhecida por nós como Via Lactea.  Quando nosso zoom se amplia ainda mais, encontramos uma vizinhança de nossa Galáxia, algumas outras galáxias – como, por exemplo, a galáxia Andromeda.  Estas galáxias foram Grupos ou Aglomerados.  A Via Lactea e Andromeda e outras galáxias menores em nossa vizinhança formam o chamado Grupo Local.  O Grupo Local contém cerca de 500 galáxias e possui um diâmetro aproximado de 7 milhões de anos-luz.
Ao aprofundarmos o zoom, encontraremos muitas dessas galáxias e que vão formando estruturas.  Os Aglomerados de galáxias se encontram com outros Aglomerados e são formados aquilo que denominamos de Superaglomerados.  Nosso Grupo Local pertence ao Superaglomerado Virgo.  Esse Superaglomerado possui cerca de 200 Aglomerados de galáxias e possui um diâmetro de cerca de 200 milhões de anos-luz.
Porém, as dimensões continuam em suas amplitudes e quando usamos o zoom para ainda além os Superaglomerados, podemos notar que estes Superaglomerados também formam estruturas que são chamadas de Filamentos.  Um famoso Filamento é referido como A Grande Muralha (The Great Wall).  A Grande Muralha possui um comprimento aproximado de 500 milhões de anos-luz e possui altura de cerca de 300 milhões de anos-luz e 15 milhões de anos-luz de espessura.
Ainda mais distante, estaremos encontrando a Grande Muralha Sloan (Sloan Great Wall) – também um Filamento porém de dimensão inteiramente diferente.  A Grande Muralha Sloan possui um comprimento aproximado de 1.3 bilhões de anos-luz!
Agora que esclarecemos sobre as estruturas no espaço, podemos começar a conversar sobre o Void, o Vazio.  Mencionamos as maiores estruturas do universo – os Filamentos todos ligados entre si como se fosse uma malha de favo de mel.  Entre os Filamentos, existe o Void, o Nada, o Vazio.  Não existe nada no Vazio, nem gás, nem poeira e certamente nem estrelas ou planetas.  No entanto, acredita-se que a tão comentada Matéria Escura exista nos Voids – mesmo que não emita luz ou radiação quaisquer e que, portanto, não é visível.





http://www.whillyard.com. 


Voids & Supervoids
Cosmic voids, and supervoids, are large volumes of space that are devoid of matter.  This includes normal matter, in the form of galaxies, and dark matter.  Initially, astronomers were not sure if the voids contained dark matter, even though there were no galaxies, but recent observations show that the halos of dark matter are not present.  The filamentary structure of galactic superclusters surrounds the voids.  While space is mostly empty, voids are large volumes, tens of megaparsecs across. The largest confirmed supervoids are about 100 Mpc (325 million light-years) or more across .  The larger known voids include the Boötes Supervoid, and the Northern and Southern Local Supervoids.  To explain the cold spot in the cosmic microwave background (CMB), some astronomers propose a huge supervoid, tentatively dubbed the Eridanus or Great supervoid.  The Capricornus void is another disputed void, but would be around 230 Mpc across.  This link has some of the latest information oncosmic voids.   


Eridanus Supervoid or Great Void
The Eridanus Supervoid, or Great Void, is conjectural, and has been suggested as a way to explain the "cold spot" in the cosmic microwave background radiation, or CMB. This would be an extraordinarily large region of the universe, at least 150 Mpc or 500 million light-years across, and possibly twice this figure.  It is also very distant at between 1.8 Gpc and 3 Gpc (6 to 10 billion light-years).  Many astronomers and cosmologists do not accept the supervoid theory for the aberration in the CMB, but many of the alternatives are even more astounding including cosmic textures and parallel universes.  So the jury remains out on this one. 

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http://www.whillyard.com. 





In astronomyvoids are the vast empty spaces between filaments (the largest-scale structures in the Universe), which contain very few, or no, galaxies. They were first discovered in 1978 during a pioneering study by Stephen Gregory and Laird A. Thompson at the Kitt Peak National Observatory.[1] Voids typically have a diameter of 11 to 150 megaparsecs; particularly large voids, defined by the absence of rich superclusters, are sometimes called "supervoids". Voids located in high-density environments are smaller than voids situated in low-density spaces of the universe.[2] Voids are believed to have been formed by baryon acoustic oscillations in the Big Bang—collapses of mass followed by implosions of the compressed baryonic matter. Starting from initially smallanisotropies due to quantum fluctuations in the early Universe, the anisotropies grew larger in scale over time. Regions of higher density collapsed more rapidly under gravity, eventually resulting in the large-scale, foam-like structure or “cosmic web” of voids and galaxy filaments seen today.

Voids appear to correlate with the observed temperature of the cosmic microwave background (CMB), due to the Sachs–Wolfe effect. Colder regions correlate with voids, whereas hotter regions correlate with filaments, because of gravitational redshifting. As the Sachs–Wolfe effect is only significant if the Universe is dominated by radiation or dark energy, the existence of voids is significant in providing physical evidence for dark energy. [3]





The Virgo Cluster, however, is merely a minor 

member of a much larger whole.  The 

neighboring superclusters are massive, most 

of them three and four times larger than the 

Virgo Cluster and spanning a distance of some 

100 million light years.  These leviathans in 

turn form massive chains and walls that 

weave throughout the cosmos.  Between 

them exists, quite literally, nothing.  These 

giant voids are hundreds of millions of light 

years in diameter and most of them contain 

absolutely nothing at all.  No stars.  No galaxy.

No matter.


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The Eridanus Supervoid is the largest supervoid (an area of the universe devoid ofgalaxies) discovered as of 2007. At a diameter of about one billion light years it is much larger than any other known void. It was discovered by linking a "cold spot" in the cosmic microwave background to an absence of radio galaxies in data of the United States National Radio Astronomy Observatory's Very Large Array Sky Survey.[2] There is some speculation that the void may be due to quantum entanglement between our universe and another.[3][4]



http://www.atlasoftheuniverse.com/nearsc.html
Massive voids separate galaxy superclusters across the Universe


Image comment: Massive voids separate galaxy superclusters across the Universe Image credits: NASA / ESA

In a new study, a team of astronomers proposes that a so-called Universe-in-mas black hole is responsible for the development of an incredibly-large void in the constellation Eridanus.
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Supervoid[
The Eridanus Supervoid is the largest supervoid (an area of the universe devoid ofgalaxies) discovered as of 2007. At a diameter of about one billion light years it is much larger than any other known void. It was discovered by linking a "cold spot" in the cosmic microwave background to an absence of radio galaxies in data of the United States National Radio Astronomy Observatory's Very Large Array Sky Survey.[2] There is some speculation that the void may be due to quantum entanglement between our universe and another.[3][4]
See also: WMAP cold spot


Great 'cosmic nothingness' found
Astronomers have found an enormous void in space
 that measures nearly a billion light-years across.
It is empty of both normal matter - such as galaxies and stars -
 and the mysterious "dark matter" that cannot be seen directly with telescopes.
 The "hole" is located in the direction of the Eridanus constellation
 and has been identified in data 
from a survey of the sky made at radio wavelengths.


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The Eridanus Void: Does a MegaMassive Black Hole One-Billion Light Years Across Exist? (A 'Galaxy' Most Popular)

Blackhole1
The apparent development of a large void of some billion light-years in diameter in the Constellation Eridanus appears to be improbable given current cosmological models. A radical and controversial theory proposes that it is a "universe-in-mass black hole" rather than hypothetical dark matter responsible for the phenomenon described as the expanding-accelerating universe. This radical theory of cosmology suggests that stars at the edge of the Hubble length universe are being consumed by a universe-in-mass black hole.


In August of 2007, astronomers at the University of Minnesota located a gigantic hole in the universe. This empty space, stretching nearly a billion light-years across, is devoid of any matter such as galaxies, stars, and gas, and neither does it contain the strange and mysterious dark matter, which can be detected but not seen.





The new survey mapped the positions of more than 100,000 galaxies. The black strips are areas the survey did not cover because matter in our own galaxy blocked the view (Illustration: Chris Fluke/Swinburne University of Technology)

Enormous cosmic voids and giant concentrations of matter have been observed in a new galaxy survey, one of the biggest completed so far. One of the voids is so large that it is difficult to explain where it came from.
.........................................
The survey also found some enormous voids – regions of space that are relatively empty, including one that is about 3.5 billion light years across.
"This is as big as I've ever seen," survey team member John Huchra of the Harvard-Smithsonian Center for Astrophysics told New Scientist.
Another large void about 1 billion light years across was discovered previously.

Curiously large

In fact the newly found void is so large that it is difficult to fit into our present understanding of the universe on the largest scales. Computer simulations show that gravity causes galaxies and galaxy clusters to get closer together over time, with voids growing between the clusters.
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Biggest void in space is 1 billion light years across

 by Anil Ananthaswamy

The biggest known hole in the universe has left a cold-spot in the cosmic microwave radiation (Illustration: Bill Saxton, NRAO/AUI/NSF, NASA)

Radio astronomers have found the biggest hole ever seen in the universe. The void, which is nearly a billion light years across, is empty of both normal matter and dark matter. The finding challenges theories of large-scale structure formation in the universe.

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The void, which is about 6 billion to 10 billion light years away, is considerably larger than any found before. Until now, optical surveys have found no voids larger than 80 megaparsecs wide - making the new hole 40 times larger in volume than the previous record holder.
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Computer simulations that recreate the formation of clusters and super-clusters have never seen voids of this size. That could be because modellers have not simulated large enough volumes to see such a void, says Rudnick. If they did, maybe a void would emerge. "It is an open question whether this will create problems for structure formation," he says.

LEIA MAIS EM 







Acessando a Animação abaixo, você poderá saber melhor sobre 
ERIDANUS SUPERVOID
 (e também sobre Fornax Cluster):

The Scale of the Universe - Interactive 
Flash Animation Credit & Copyright: Cary & Michael Huang


Explanation: What does the universe look like on small scales? On large scales? Humanity is discovering that the universe is a very different place on every proportion that has been explored. For example, so far as we know, every tiny proton is exactly the same, but every huge galaxy is different. On more familiar scales, a small glass table top to a human is a vast plane of strange smoothness to a dust mite -- possibly speckled with cell boulders. Not all scale lengths are well explored -- what happens to the smallest mist droplets you sneeze, for example, is a topic of active research -- and possibly useful to know to help stop the spread of disease. The above interactive flash animation, a modern version of the classic video Powers of Ten, is a new window to many of the known scales of our universe. By moving the scroll bar across the bottom, you can explore a diversity of sizes, while clicking on different items will bring up descriptive information.

Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
NASA Official: Phillip Newman Specific rights apply.
A service of: ASD at NASA / GSFC














SAIBA MAIS, MUITO MAIS!,
 SOBRE OS OBJETOS 
NA CONSTELAÇÃO DE ERIDANUS, O RIO ERIDANO:


DOCdb
Deep Sky Observer's Companion – the online database

listing objects by constellation

Searching for all objects in Eridanus.









Map Maker: Johann Bayer



Os desenhos formados pelas estrelas
 – As Constelações - 
são como janelas que se abrem para a infinitude do universo
 e que possibilitam nossa mente a ir percebendo 
que existe mais, bem mais, 
entre o céu e a terra 
bem como percebendo que o caos, 
vagarosamente,
 vai se tornando Cosmos e sendo por nossa mente conscientizado.  


Quer dizer, 

nossa mente é tão infinita quanto infinito é o Cosmos.

COM UM ABRAÇO ESTRELADO,
Janine Milward






Visitando os Sites abaixo,
 você conseguirá informações atualizadas e preciosas
sobre os Objetos Celestiais de seu interesse:

NASA/IPAC EXTRAGALACTIC DATABASE –
NASA/IPAC Extragalactic Database (NED) -  operated by the Jet Propulsion Laboratory, California Institute of Technology, under contract with the National Aeronautics and Space Administration.


THE NIGHT SKY ATLAS
The night sky atlas creates images of any part of the night sky, allowing easy location of any object. Detailed chart images show all stars visible to the naked eye, the constellations, Messier objects, and names of the brightest stars.

The Internet STELLAR DATABASE

- stars within 75 light-years.  (Plus some of the more well-known "name brand" stars farther away.)