Starstruck: Awe-inspiring cross-section of the cosmos snapped by Hubble reveals thousands of galaxies as big as the Milky Way
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You might think the Milky Way is pretty big – after all, it is thought to contain hundreds of billions of stars.
But a newly released image of a galaxy cluster taken by the Hubble Space Telescope shows how small our own galaxy really is.
The 14-hour exposure of just a portion of the cosmos pictures thousands of galaxies across space and time, from near neighbours to remnants of the early universe.
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Mind-boggling: Hubble's images might look flat, but this 14-hour exposure released by Nasa and Esa shows a remarkable depth of field that lets us see into deep space more than halfway to the edge of the observable Universe
The Nasa and Esa photo shows objects around a billion times fainter than can be seen with the naked eye.
It highlights a remarkable variety of objects at different distances from us, extending back over halfway to the edge of the observable universe.
The galaxies in this image mostly lie within about 5 billion light-years of us, but the field also contains objects that are both closer and more distant.
Studies of this region of the sky have shown that many of the objects that appear to lie close together may actually be billions of light-years apart.
This is because several groups of galaxies lie along our line of sight, creating something of an optical illusion.
WHAT IS GRAVITATIONAL LENSING?
Gravitational lensing occurs when galaxies and other objects amplify the light coming from other distant objects.
It enables telescopes like Hubble to see objects that would otherwise be too faint and far away.
This effect will be exploited during the Frontier Fields observing campaign in the near future.
This will combine the power of Hubble with the natural amplification caused by strong gravitational lensing of distant galaxy clusters to study the past Universe.
Hubble's cross-section of the universe is completed by distorted images of galaxies in the very distant background.
These objects are sometimes distorted due to a process called gravitational lensing, an extremely valuable technique in astronomy for studying very distant objects.
This lensing is caused by the bending of the space-time continuum by massive galaxies lying close to our line of sight to distant objects.
One of the lens systems visible here is called CLASS B1608+656, which appears as a small loop in the centre of the image.
It features two foreground galaxies distorting and amplifying the light of a distant quasar.
The light from this bright disc of matter, which is currently falling into a black hole, has taken nine billion years to reach us -- two thirds of the age of the Universe.
As well as CLASS B1608+656, astronomers have identified two other gravitational lenses within this image.
Two galaxies, dubbed Fred and Ginger by the researchers who studied them, contain enough mass to visibly distort the light from objects behind them.
Fred, also known slightly less imaginatively as [FMK2006] ACS J160919+6532, lies near the lens galaxies in CLASS B1608+656, while Ginger ([FMK2006] ACS J160910+6532) is markedly closer to us.
Most of the galaxies visible in this Hubble image are members of a huge cluster called CLASS B1608+656, which lies about five billion light-years away, but the field also contains other objects that are both significantly closer and far more distant including two gravitational lenses dubbed Fred and Ginger. These contain enough mass to visibly distort the light from objects behind them
This Digitized Sky Survey (DSS) image was taken with a ground based telescope and shows the region surrounding the galaxy cluster called CLASS B1608+656
The Hubble Space Telescope, a joint Esa and Nasa project launched on 24 April 1990, has made some of the most dramatic discoveries in the history of astronomy. From its vantage point 370 miles (600 kilometres) above Earth, Hubble can detect light with 'eyes' 5 times sharper than the best ground-based telescopes and looks deep into space where some of the most profound mysteries are still buried in the mists of time
Despite their different distances from us, both can be seen near to CLASS B1608+656 in the central region of this Hubble image.
To capture distant and dim objects like these, Hubble required a long exposure.
The image is made up of visible and infrared observations with a total exposure time of 14 hours.
The Hubble Space Telescope is a project of international cooperation between Esa and Nasa.
This particular image was actually spotted by contestant Adam Kill in the 2012 Hubble's Hidden Treasures competition.
Hidden Treasures invited members of the public to search Hubble's science for the best overlooked images that have never been seen by a general audience.
This image of CLASS B1608+656 has been well-studied by scientists over the years, but this is the first time it has been published in full.
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