Wikipedia

File:QSO B0957+0561.jpg

File originale ‎(4 209 × 2 957 pixel, dimensione del file: 4,62 MB, tipo MIME: image/jpeg)

Logo di Commons
Logo di Commons
 Questo file e la sua pagina di descrizione (discussione · modifica) si trovano su Wikimedia Commons (?)

Dettagli

Descrizione
English: In this new Hubble image two objects are clearly visible, shining brightly. When they were first discovered in 1979, they were thought to be separate objects — however, astronomers soon realised that these twins are a little too identical! They are close together, lie at the same distance from us, and have surprisingly similar properties. The reason they are so similar is not some bizarre coincidence; they are in fact the same object.

These cosmic doppelgangers make up a double quasar known as QSO 0957+561, also known as the "Twin Quasar", which lies just under 9 billion light-years from Earth. Quasars are the intensely powerful centres of distant galaxies. So, why are we seeing this quasar twice?

Some 4 billion light-years from Earth — and directly in our line of sight — is the huge galaxy YGKOW G1. This galaxy was the first ever observed gravitational lens, an object with a mass so great that it can bend the light from objects lying behind it. This phenomenon not only allows us to see objects that would otherwise be too remote, in cases like this it also allows us to see them twice over.

Along with the cluster of galaxies in which it resides, YGKOW G1 exerts an enormous gravitational force. This doesn't just affect the galaxy's shape, the stars that it forms, and the objects around it — it affects the very space it sits in, warping and bending the environment and producing bizarre effects, such as this quasar double image.

This observation of gravitational lensing, the first of its kind, meant more than just the discovery of an impressive optical illusion allowing telescopes like Hubble to effectively see behind an intervening galaxy. It was evidence for Einstein's theory of general relativity. This theory had identified gravitational lensing as one of its only observable effects, but until this observation no such lensing had been observed since the idea was first mooted in 1936.
Data (released)
Fonte http://www.spacetelescope.org/images/potw1403a/
Autore ESA/Hubble & NASA

Licenza

w:it:Creative Commons
attribuzione
attribuzione
 ESA/Hubble images, videos and web texts are released by the ESA under the Creative Commons Attribution 4.0 International license and may on a non-exclusive basis be reproduced without fee provided they are clearly and visibly credited. Detailed conditions are below; see the ESA copyright statement for full information. For images created by NASA or on the hubblesite.org website, or for ESA/Hubble images on the esahubble.org site before 2009, use the {{PD-Hubble}} tag.
Conditions:
  • The full image or footage credit must be presented in a clear and readable manner to all users, with the wording unaltered (for example: "ESA/Hubble"). Web texts should be credited to ESA/Hubble (except when used by media). The credit should not be hidden or disassociated from the image footage. Links should be active if the credit is online. See the usage rights Q&A section on the ESA copyright page for guidance.
  • ESA/Hubble materials may not be used to state or imply the endorsement by ESA/Hubble or any ESA/Hubble employee of a commercial product or service.
  • ESA/Hubble requests a copy of the product sent to them to be indexed in their archive.
  • If an image shows an identifiable person, using that image for commercial purposes may infringe that person's right of privacy, and separate permission should be obtained from the individual.
  • If images or visuals are changed significantly from the original work (apart from resizing, cropping), we suggest that the changes are mentioned after the credit line. For example "Original image by ESA/Hubble (M. Kornmesser), warping and recolouring by NN".

Notes:

  • Note that this general permission does not extend to the use of ESA/Hubble's logo, which shall remain protected and may not be used or reproduced without prior and individual written consent of ESA/Hubble.
  • Also note that music, scientific papers and code on the esahubble.org site are not released under this license and can not be used for non-ESA/Hubble products.
  • By reproducing ESA/Hubble material, in part or in full, the user acknowledges the terms on which such use is permitted.
w:it:Creative Commons
attribuzione
Questo file è disponibile in base alla licenza Creative Commons Attribuzione 4.0 Internazionale
Attribuzione: ESA/Hubble & NASA
Tu sei libero:
  • di condividere – di copiare, distribuire e trasmettere quest'opera
  • di modificare – di adattare l'opera
Alle seguenti condizioni:
  • attribuzione – Devi fornire i crediti appropriati, un collegamento alla licenza e indicare se sono state apportate modifiche. Puoi farlo in qualsiasi modo ragionevole, ma non in alcun modo che suggerisca che il licenziante approvi te o il tuo uso.

Didascalie

Aggiungi una brevissima spiegazione di ciò che questo file rappresenta

Elementi ritratti in questo file

raffigura

Cronologia del file

Fare clic su un gruppo data/ora per vedere il file come si presentava nel momento indicato.

Data/OraMiniaturaDimensioniUtenteCommento
attuale01:27, 21 gen 2014Miniatura della versione delle 01:27, 21 gen 20144 209 × 2 957 (4,62 MB)JmencisomUser created page with UploadWizard

Le seguenti 2 pagine usano questo file:

Utilizzo globale del file

Anche i seguenti wiki usano questo file:

Metadati

Questo file contiene informazioni aggiuntive, probabilmente aggiunte dalla fotocamera o dallo scanner usati per crearlo o digitalizzarlo. Se il file è stato modificato, alcuni dettagli potrebbero non corrispondere alla realtà.

Estratto da "https://it.wikipedia.org/wiki/File:QSO_B0957%2B0561.jpg"