Post by Andrei Tchentchik on Jun 24, 2019 15:32:36 GMT 2
(.#212).- The doyenne of the cosmos at 13 billion years
The doyenne of the cosmos at 13 billion years ..
By Marc Mennessier - Updated 2210/2010 at 10:45
The galaxy was observed with the Very Large Telescope, a set of four telescopes located in the Atacama Desert. (Photo credits: ESO / H.H.Hayer).
A team of astronomers has just spotted the oldest glow emitted by a galaxy, shortly after the big bang.
It is the oldest object known to date. The farthest too. French and British astronomers have just shown that the galaxy UDFy-38135539, located in the constellation Fourneau, emitted its first light more than 13 billion years ago, when the universe had only 600 million years. That's a little less than one twentieth of his current age.
This cosmic dean was first spotted in 2009 by the Hubble Space Telescope. Its extremely tenuous glow was then observed and analyzed for 16 hours at the Very Large Telescope (VLT), located on Mount Cerro Paranal in the Atacama Desert in northern Chile. The results published the day before yesterday in the British journal Nature show that ultraviolet light, a wavelength of 0.12 millionth of a meter (microns), emitted initially by this galaxy, arrives today on Earth in the form of of infrared radiation with a wavelength of 1.16 micron. This redshift, which reflects the loss of energy associated with the expansion and expansion of the Universe since those distant times and therefore the distance that now separates us from UDFy-38135539, reaches a record value of 8, 55. Never seen in the history of astronomy! The previous record (8.2), awarded last year to a "gamma burst" (extremely violent light flash linked to the death of a massive star), is beaten.
Hydrogen mist
"We saw this galaxy when the Universe was less than 600 million years old. This is the most distant object ever observed so far, "says Matthew Lehnert, CNRS astronomer at the Paris-Meudon Observatory and lead author of the study.
"These are the first confirmed observations of a galaxy whose light dispels the opaque mist of hydrogen that filled the cosmos in the early days of the Universe," said the European Southern Observatory (ESO) in a statement. , owner of the VLT. Without this fog, the first stars could have "lighted up" 400 million years only after the big bang. In order for the light to escape, it was necessary for the galaxy to emit enough energy to ionize the hydrogen and thus make the Universe transparent.
Two other galaxies among the five detected by Hubble are under study at the VLT. Will one of them be the new dean of the cosmos ?
F I N .
The doyenne of the cosmos at 13 billion years ..
By Marc Mennessier - Updated 2210/2010 at 10:45
The galaxy was observed with the Very Large Telescope, a set of four telescopes located in the Atacama Desert. (Photo credits: ESO / H.H.Hayer).
A team of astronomers has just spotted the oldest glow emitted by a galaxy, shortly after the big bang.
It is the oldest object known to date. The farthest too. French and British astronomers have just shown that the galaxy UDFy-38135539, located in the constellation Fourneau, emitted its first light more than 13 billion years ago, when the universe had only 600 million years. That's a little less than one twentieth of his current age.
This cosmic dean was first spotted in 2009 by the Hubble Space Telescope. Its extremely tenuous glow was then observed and analyzed for 16 hours at the Very Large Telescope (VLT), located on Mount Cerro Paranal in the Atacama Desert in northern Chile. The results published the day before yesterday in the British journal Nature show that ultraviolet light, a wavelength of 0.12 millionth of a meter (microns), emitted initially by this galaxy, arrives today on Earth in the form of of infrared radiation with a wavelength of 1.16 micron. This redshift, which reflects the loss of energy associated with the expansion and expansion of the Universe since those distant times and therefore the distance that now separates us from UDFy-38135539, reaches a record value of 8, 55. Never seen in the history of astronomy! The previous record (8.2), awarded last year to a "gamma burst" (extremely violent light flash linked to the death of a massive star), is beaten.
Hydrogen mist
"We saw this galaxy when the Universe was less than 600 million years old. This is the most distant object ever observed so far, "says Matthew Lehnert, CNRS astronomer at the Paris-Meudon Observatory and lead author of the study.
"These are the first confirmed observations of a galaxy whose light dispels the opaque mist of hydrogen that filled the cosmos in the early days of the Universe," said the European Southern Observatory (ESO) in a statement. , owner of the VLT. Without this fog, the first stars could have "lighted up" 400 million years only after the big bang. In order for the light to escape, it was necessary for the galaxy to emit enough energy to ionize the hydrogen and thus make the Universe transparent.
Two other galaxies among the five detected by Hubble are under study at the VLT. Will one of them be the new dean of the cosmos ?
F I N .
