Nouvelle découverte dans le cosmos grâce au telescope Hubble qui a détecté une galaxie datant d'à peine 400 millions d'annees après le big bang. La galaxie a été nommée GN-z11 par l'equipe de chercheurs qui a identifié l'objet.
"To determine large distances, like the one to GN-z11, astronomers measure the redshift of the observed object. This phenomenon is a result of the expansion of the Universe; every distant object in the Universe appears to be receding from us and as a result its light is stretched to longer, redder wavelengths."
"Before astronomers determined the distance to GN-z11, the most distant measured galaxy, EGSY8p7, had a redshift of 8.68. Now, the team has confirmed GN-z11’s distance to be at a redshift of 11.1, which corresponds to 400 million years after the Big Bang."
Cette nouvelle soulève de nouvelles questions non resolues par l'état des connaissances actuels::
“It’s amazing that a galaxy so massive existed only 200 million to 300 million years after the very first stars started to form. It takes really fast growth, producing stars at a huge rate, to have formed a galaxy that is a billion solar masses so soon,” explains Garth Illingworth of the University of California, Santa Cruz.
Marijn Franx, a member of the team from the University of Leiden highlights: “The discovery of GN-z11 was a great surprise to us, as our earlier work had suggested that such bright galaxies should not exist so early in the Universe.” His colleague Ivo Labbe adds: “The discovery of GN-z11 showed us that our knowledge about the early Universe is still very restricted. How GN-z11 was created remains somewhat of a mystery for now. Probably we are seeing the first generations of stars forming around black holes?”
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