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Are these the most distant stars ever seen? Faint stars more than 13 BILLION light-years from Earth could could reveal how the universe emerged from its ‘dark age’

Astronomers have used gravitational lensing to observe ancient stars
Their light is obscured by a galaxy cluster 13 billion light-years away
Scientists took three snapshots and merged them to form a single picture
It is hoped the distant snapshot could help explain how the early universe transitioned from a neutral state, when the very first stars formed

Published: 14:27, 20 May 2016 | Updated: 14:27, 20 May 2016

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Astronomers have managed to grab a glimpse of one of the most distant galaxies from our planet ever observed.

Light leaving its stars will have travelled a staggering length of time, more than 13 billion years, before reaching Earth, providing scientists a glimpse into the youth of our universe.

Scientists hope that such glimpses could help to understand how the early universe transitioned from a neutral black void to an explosion of starlight.

Astronomers have used used gravitational lensing to obtain multiple snapshots of faint stars which lay behind a distant galaxy cluster, called MACS J2129.4-0741, more than 13 billion light years away. Taking three separate images of light which had been bent around the cluster, they were able to merge them together to form a single image of the faint distant stars hidden behind (pictured)

At such vast distances from Earth, light from galaxies is incredibly faint, but astronomers can turn to gravity for a helping hand.

When light travels through the universe its path can become bent by gravity, as predicted by Einstein's Theory of General Relativity.

In the case of galaxies, which have more mass, light can be bent more, and can be used as a lens to refocus light coming from behind them, by bending the light around them – an effect called gravitational lensing.

An international team, led by researchers at the University of California, Davis, used gravitational lensing to obtain multiple snapshots of the stars which lay behind a distant galaxy cluster, called MACS J2129.4-0741.

An international team, led by researchers at the University of California, Davis, used a special instrument on the 10-metre telescope at the Keck Observatory in Hawaii (pictured), as well as images from the Hubble Space Telescope

DO ANCIENT STARS HOLD THE KEY TO UNIVERSAL 'DARK AGE'?

Astronomers have been able to observe some of the farthest stars from Earth.

Their light is obscured by a galaxy cluster 13 billion light-years away, but the team used gravitational lensing to see faint light as it was bent around.

They took three snapshots and merged them to form a single picture.

It is hoped the distant snapshot could help explain how the early universe transitioned from a neutral state, when the very first stars formed.

Taking three separate images of light which had been bent around the cluster, they were able to merge them together to form a single image of the faint stars hidden behind.

'This galaxy is exciting because the team infers a very low stellar mass, or only 1 percent of 1 percent of the Milky Way galaxy,' explained Marc Kassis, an astronomer at the Keck Observatory in Hawaii, where the observations were captured.

Beyond getting a snap of distant stars, hidden by galaxy clusters, it could help scientists to explain how the universe evolved.

After the big bang, physicists believe the universe entered a dark age lasting hundreds of millions of years, in which the once charged hydrogen gas became neutral.

But around 13 million years something switched, causing the particles to become charged again, called the 're-ionization epoch', at which point stars began to appear.

When light travels through the universe its path is bent by gravity, as predicted by Einstein's theory of relativity. Galaxies have enormous mass, so bend light more. But astronomers can take advantage of this to refocus light being bent, using the galaxy as a lens - an effect called gravitational lensing. Stock image

Dr Kassis explained: 'It's a very, very small galaxy and at such a great distance, it's a clue in answering one of the fundamental questions astronomy is trying to understand: What is causing the hydrogen gas at the very beginning of the universe to go from neutral to ionized about 13 billion years ago? That's when stars turned on and matter became more complex.'

Professor Marusa Bradac, a physicist at UCD and one of the lead researchers on the project said: 'Keck Observatory's telescopes are simply the best in the world for this work.'

She added: 'Their power, paired with the gravitational force of a massive cluster of galaxies, allows us to truly see where no human has seen before.'

The findings were published this week in the journal Astrophysical Journal Letters.

WHAT IS THE THEORY OF RELATIVITY?

Albert Einstein (pictured) came up with his General Theory of Relativity in 1916

In 1905, Albert Einstein determined that the laws of physics are the same for all non-accelerating observers, and that the speed of light in a vacuum was independent of the motion of all observers - known as the theory of special relativity.

This groundbreaking work introduced a new framework for all of physics, and proposed new concepts of space and time.

He then spent 10 years trying to include acceleration in the theory, finally publishing his theory of general relativity in 1915.

This determined that massive objects cause a distortion in space-time, which is felt as gravity.

At its simplest, it can be thought of as a giant rubber sheet with a bowling ball in the centre.

As the ball warps the sheet, a planet bends the fabric of space-time, creating the force that we feel as gravity.

Any object that comes near to the body falls towards it because of the effect.

Einstein predicted that if two massive bodies came together it would create such a huge ripple in space time that it should be detectable on Earth.

It was most recently demonstrated in the hit film film Interstellar.

In a segment that saw the crew visit a planet which fell within the gravitational grasp of a huge black hole, the event caused time to slow down massively.

Crew members on the planet barely aged while those on the ship were decades older on their return.