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Sussex scientist reveals detailed view of far galaxies

One of the first areas on the sky observed by Herschel was the dense galaxy cluster Abell2218, which is so massive that it acts as a gigantic lens distorting the distant light and magnifying galaxies lying at great distances behind it.

Amazing new views of distant galaxies as they were billions of years ago have been released by a team of scientists led by University of Sussex astrophysicist Seb Oliver.

Date captured by ESA's Herschel Space Observatory - carrying the largest mirror ever launched into space - has just been publicly released, allowing the astronomers to share in Herschel's observations of distant galaxies.   

The new data is part of the Herschel Multi-tiered Extragalactic Survey (HerMES), led by Professor Oliver at the University of Sussex in the UK and Dr Jamie Bock at the NASA Jet Propulsion Laboratory and California Institute of Technology.

The HerMES project is providing a view of the distant Universe at wavelengths that can be observed only from space.  The SPIRE camera on board Herschel allows it to "see" images in three wavelength colours hardly ever used in astronomy until now, allowing astronomers to view cool objects that were previously invisible.  The appearance of an object in these three colours provides information on its temperature, distance and luminosity.

From its vantage point nearly 1.5 million km from Earth (1 million miles), the Herschel spacecraft has given astronomers new insights into the different types of galaxy in the distant Universe and will allow them to explore part of the Universe as it was some eleven billion years ago or just three billion years after the Big Bang.

Herschel can see back in time because the light left the stars making up the distant galaxies billions of years before our planet Earth was formed and has been travelling through space ever since, only now to be captured by the spacecraft's sensitive eyes.

Professor Oliver says: We have made these images and lists of galaxies available to all astronomers sooner than we were obliged to because Herschel is a fantastic mission but has a limited lifetime, so it is vital that it is used for the best science.  We hope that other astronomers will want to use Herschel and many other telescopes to study the galaxies we have discovered."

Some of the data being released focus on a massive cluster of galaxies called Abell 2218.  At a distance of over two billion light years from Earth, the huge mass of the cluster warps the surrounding space, bending and magnifying light from background galaxies in a manner similar to light being magnified by a normal glass lens. 

Abell 2218 is famous for being one of the best known examples of this "gravitational lensing".  The effect, first predicted by Einstein in the early 20th century, means that the background galaxies are magnified, allowing a much clearer view of objects as they were over 11 billion years ago - less than 3 billion years after the Big Bang.

The Herschel observations of these distant galaxies tell astronomers how fast they were forming stars at these early times, and help to build up a picture of how galaxies have evolved over the course of billions of years.


Notes for Editors

 

For more information, please see:

HerMES Website: http://hermes.sussex.ac.uk

UK Herschel Website: http://herschel.cf.ac.uk

ESA Herschel Websites: http://esa.int/herschel and http://sci.esa.int/herschel

ESA Herschel Science Centre (HSC) website: http://herschel.esac.esa.int

Pictures caption: The region of sky around the massive galaxy cluster Abell 2218, as seen by Herschel and Hubble. The three wavelength bands are presented here as a false-colour composite.  The large yellow blob is actually a much more distant galaxy - the light it is emitting is being bent and magnified by the immense mass of the Abell 2218 cluster, allowing astronomers to see it in more detail than would otherwise be possible without this chance alignment.

It is seen as it was around 2.6 billion years after the Big Bang, providing a glimpse into the Universe's history.  The other structures in the image are largely due to much closer, fainter galaxies.  The public release of the Herschel data is allowing astronomers to better determine the formation and evolution of galaxies from soon after the Big Bang right up to today. Image credit: ESA/SPIRE and HerMES Consortia.

Home Page Image: ESA/NASA/STScI.

University of Sussex Press office contacts: Maggie Clune, Jacqui Bealing and Daniëlle Treanor. Tel: 01273 678 888. Email: press@sussex.ac.uk

View press releases online at: http://www.sussex.ac.uk/newsandevents/


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Last updated: Monday, 5 July 2010

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