Astronomers find most remote galaxy ever seen... 13 BILLION light years away - Astronomers have discovered the oldest and most distant object in the universe - a galaxy so far away that its light has taken 13.1 billion years to reach the Earth. The galaxy, which was spotted by Europe's Very Large Telescope in Chile, is the most remote cluster of stars, gas and dust ever measured.
This image taken by the Hubble telescope shows the galaxy, named UDFy-38135539. It is the faint white dot within the red circle to the left of the picture. Light from the galaxy that reaches Earth today was emitted when the cosmos was only 600million years old. It has taken 13.1billion years, travelling at 186,000 miles per second, for this smudge of infant light to arrive
It is so distant, scientists are observing it when the universe was in its infancy - aged just 600 million years old, or four per cent of its present age. Dr Nicole Nesvadba of the Institute of Space Astrophysics in Paris said: 'Measuring the most distant galaxy so far is very exciting in itself, but the astrophysical implications of this detection are even more important.
'This is the first time we know for sure that we are looking at one of the galaxies that cleared out the fog which had filled the very early universe.'
Each time astronomers gaze at distant stars, they are looking back in time.Light from nearby stars takes just a few years to reach the Earth. But light from remote galaxies takes billions of years to travel across the universe.
The galaxy, named UDFy -38135539, was spotted by the Hubble space telescope last year. Its age has now been confirmed by the European Organisation for Astronomical Research in the Southern Hemisphere's Very Large Telescope.
Studying far distant galaxies is difficult. By the time the light from their millions of stars reaches the Earth, galaxies appear faint and small. And most of this dim light falls in the infra-red spectrum because its wavelength has been stretched by the expansion of the universe - a phenomenon known as redshift.
To add to the difficulties, the galaxy is being observed at a time when the universe was not fully transparent and was filled with a fog of hydrogen.The European team observed the galaxy for 16 hours and analysed the results for two months. The findings are published in the journal Nature.
Dr Matt Lehnert of the Paris Observatory, said: 'Using the ESO (European Southern Observatory) Very Large Telescope we have confirmed a galaxy spotted earlier using Hubble is the most remote object identified so far in the universe.
'The power of the VLT allows us to actually measure the distance to this very faint galaxy and we find we are seeing it when the universe was less than 600 million years old.'
Co-author of the research, Dr Mark Swinbank of Durham University, said the glow from the ancient galaxy was not strong enough on its own to clear the hydrogen fog.
'There must be other galaxies, probably fainter and less massive nearby companions of UDFy-38135539, which also helped make the space around the galaxy transparent,' he said.
'Without this additional help the light from the galaxy, no matter how brilliant, would have been trapped in the surrounding hydrogen fog and we would not have been able to detect it'.
The universe was created in the Big Bang around 13.7 billion years ago. Stars and galaxies started to form around 300 million years later. Our Sun was born around five billion years ago, while life first appeared on the Earth around 3.7 billion years ago.
Dr Swinbank said: 'Two years ago astronauts fitted Hubble with new more powerful cameras during a renovation that could delve much deeper into space.
'They released the data into the scientific community and that is how the faint glow of UDFy-38135539 was first identified. But it needed confirmation and we did this after sixteen hours of observations.
'When you delve into "stellar archaeology" you find some of the first stars in the Milky Way are 10 to 13 billion years old.
'Other galaxies far away can show how the Milky Way started - and eventually led to us. Our Sun, for instance, is only five billion years old and we want to know how that formed.'
Shortly after the Big Bang the universe was a cold and opaque place and this sombre era is dubbed the 'Dark Ages'. A few hundred million years later the first generation of stars and galaxies produced intense ultraviolet radiation, gradually lifting the hydrogen fog over the universe.
This was the end of the Dark Ages and, with a term again taken over from human history, is sometimes referred to as the 'Cosmic Renaissance'.Astronomers are trying to pin down when and how exactly the Dark Ages finished. This requires looking for the remotest objects, a challenge that only the largest telescopes, combined with a very careful observing strategy, can take up.
One of the surprising things about the discovery described in Nature is the glow from UDFy-38135539 seems not to be strong enough on its own to clear out the hydrogen fog.
Dr Swinbank said: 'There must be other galaxies, probably fainter and less massive nearby companions of UDFy-38135539, which also helped make the space around the galaxy transparent.
'Without this additional help the light from the galaxy, no matter how brilliant, would have been trapped in the surrounding hydrogen fog and we would not have been able to detect it.' ( dailymail.co.uk )
This image taken by the Hubble telescope shows the galaxy, named UDFy-38135539. It is the faint white dot within the red circle to the left of the picture. Light from the galaxy that reaches Earth today was emitted when the cosmos was only 600million years old. It has taken 13.1billion years, travelling at 186,000 miles per second, for this smudge of infant light to arrive
It is so distant, scientists are observing it when the universe was in its infancy - aged just 600 million years old, or four per cent of its present age. Dr Nicole Nesvadba of the Institute of Space Astrophysics in Paris said: 'Measuring the most distant galaxy so far is very exciting in itself, but the astrophysical implications of this detection are even more important.
'This is the first time we know for sure that we are looking at one of the galaxies that cleared out the fog which had filled the very early universe.'
Each time astronomers gaze at distant stars, they are looking back in time.Light from nearby stars takes just a few years to reach the Earth. But light from remote galaxies takes billions of years to travel across the universe.
The galaxy, named UDFy -38135539, was spotted by the Hubble space telescope last year. Its age has now been confirmed by the European Organisation for Astronomical Research in the Southern Hemisphere's Very Large Telescope.
Studying far distant galaxies is difficult. By the time the light from their millions of stars reaches the Earth, galaxies appear faint and small. And most of this dim light falls in the infra-red spectrum because its wavelength has been stretched by the expansion of the universe - a phenomenon known as redshift.
To add to the difficulties, the galaxy is being observed at a time when the universe was not fully transparent and was filled with a fog of hydrogen.The European team observed the galaxy for 16 hours and analysed the results for two months. The findings are published in the journal Nature.
Dr Matt Lehnert of the Paris Observatory, said: 'Using the ESO (European Southern Observatory) Very Large Telescope we have confirmed a galaxy spotted earlier using Hubble is the most remote object identified so far in the universe.
'The power of the VLT allows us to actually measure the distance to this very faint galaxy and we find we are seeing it when the universe was less than 600 million years old.'
Co-author of the research, Dr Mark Swinbank of Durham University, said the glow from the ancient galaxy was not strong enough on its own to clear the hydrogen fog.
'There must be other galaxies, probably fainter and less massive nearby companions of UDFy-38135539, which also helped make the space around the galaxy transparent,' he said.
'Without this additional help the light from the galaxy, no matter how brilliant, would have been trapped in the surrounding hydrogen fog and we would not have been able to detect it'.
The universe was created in the Big Bang around 13.7 billion years ago. Stars and galaxies started to form around 300 million years later. Our Sun was born around five billion years ago, while life first appeared on the Earth around 3.7 billion years ago.
Dr Swinbank said: 'Two years ago astronauts fitted Hubble with new more powerful cameras during a renovation that could delve much deeper into space.
'They released the data into the scientific community and that is how the faint glow of UDFy-38135539 was first identified. But it needed confirmation and we did this after sixteen hours of observations.
'When you delve into "stellar archaeology" you find some of the first stars in the Milky Way are 10 to 13 billion years old.
'Other galaxies far away can show how the Milky Way started - and eventually led to us. Our Sun, for instance, is only five billion years old and we want to know how that formed.'
Shortly after the Big Bang the universe was a cold and opaque place and this sombre era is dubbed the 'Dark Ages'. A few hundred million years later the first generation of stars and galaxies produced intense ultraviolet radiation, gradually lifting the hydrogen fog over the universe.
This was the end of the Dark Ages and, with a term again taken over from human history, is sometimes referred to as the 'Cosmic Renaissance'.Astronomers are trying to pin down when and how exactly the Dark Ages finished. This requires looking for the remotest objects, a challenge that only the largest telescopes, combined with a very careful observing strategy, can take up.
One of the surprising things about the discovery described in Nature is the glow from UDFy-38135539 seems not to be strong enough on its own to clear out the hydrogen fog.
Dr Swinbank said: 'There must be other galaxies, probably fainter and less massive nearby companions of UDFy-38135539, which also helped make the space around the galaxy transparent.
'Without this additional help the light from the galaxy, no matter how brilliant, would have been trapped in the surrounding hydrogen fog and we would not have been able to detect it.' ( dailymail.co.uk )
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