The e-MERLIN image is shown in false-colour with a colour table ranging from blue through red to white, where the colours represent the brightness of the radio emission. The HST image is made from WFPC2 images through two filters: the F555W filter (V-band) is coloured green and the F814W filter (I-band) is coloured red.
Credit: Jodrell Bank Centre for Astrophysics, University of Manchester
This is a wide-field composite e-MERLIN (radio) and HST (optical) image of the Double Quasar. Here the lensed quasar images are visible as the two bright objects, one above the other, separated by about 6 arcseconds. The radio emission seen by e-MERLIN is produced by the central black hole in both lensed images. The image also shows radio emission thought to be associated with the black hole at the centre of the lensing galaxy (just above the lower quasar image) and the radio jet arcing away from the upper quasar image. The head of the counter jet which is ejected in the opposite direction is also visible to the right.
Credit: Jodrell Bank Centre for Astrophysics, University of Manchester
This image is the whole field of view of the Double Quasar as seen by e-MERLIN alone. This is a false-colour image where the range of colours represents the brightness of the radio emission.
Credit: Jodrell Bank Centre for Astrophysics, University of Manchester
This is a labelled version of the whole field of view of the Double Quasar as seen by e-MERLIN alone.
Credit: Jodrell Bank Centre for Astrophysics, University of Manchester
Black holes and warped space: New UK telescope shows off first images
9 Dec 2010
This dramatic image is the first to be produced by e-MERLIN, a powerful new array of radio telescopes linked across the UK.
Spearheaded by the University of Manchester's Jodrell Bank Observatory and funded by the Science and Technology Facilities Council, the e-MERLIN telescope will allow astronomers to address key questions relating to the origin and evolution of galaxies, stars and planets.
To demonstrate its capabilities, University of Manchester astronomers turned the new telescope array toward the "Double Quasar". This enigmatic object, first discovered by Jodrell Bank, is a famous example of Einstein's theory of gravity in action.
The new image shows how the light from a quasar billions of light years away is bent around a foreground galaxy by the curvature of space. This light has been travelling for 9 billion years before it reached the Earth. The quasar is a galaxy powered by a super-massive black hole, leading to the ejection of jets of matter moving at almost the speed of light - one of which can be seen arcing to the left in this new e-MERLIN image.
The warping of space results in a 'gravitational lens' producing multiple images of the same quasar - the two brightest of these lensed images can be seen here as two bright objects, one below the other. The foreground galaxy whose mass is responsible for the lensing effect is also visible just above the lower quasar image. The radio emission seen in the e-MERLIN image suggests that this galaxy also harbours a black hole, albeit somewhat smaller.
The UK's national facility for radio astronomy, e-MERLIN is now set to produce increasingly-detailed radio images of stars and galaxies using seven telescopes spread up to 220 km apart across the UK and working as one. This combination of widely-spread telescopes provides astronomers with a powerful 'zoom lens' with which they can study the fine details of astronomical events out towards the edge of the observable universe.
The radio signals collected by the telescopes are brought back to Jodrell Bank using a new optical fibre network. These fibre links and advanced electronic receivers will allow astronomers to collect far more data and so see in a single day what would have previously taken them more than a year of observations.
In parallel with this successful demonstration of the new telescope system, work has begun on 'early science' observations intended to rigorously test its capabilities. The project has attracted astronomers from over 100 institutes across the world who will use e-MERLIN to study a huge range of astrophysics. This includes star birth and death, black holes and galaxy evolution, pulsars (the collapsed cores of exploded stars) and young planets forming around nearby stars.
The e-MERLIN project has been funded by the Science and Technology Facilities Council (STFC), the Northwest Development Agency, The University of Manchester, The University of Cambridge and Liverpool John Moores University. It is being operated by STFC and the University of Manchester.
Minister for Science and Universities, David Willetts said:
"The image produced by the e-Merlin telescope is inspiring to all with an interest in the space sector.
"I am confident this impressive project will reap significant scientific rewards - it demonstrates how effective British universities are in this field."
Professor Simon Garrington, Director of e-MERLIN at the University of Manchester, says:
"This first image demonstrates the success of the complex new system of electronics and optical fibre links.
"It is also testament to the hard work put in by our engineers, scientists and technicians to turn our vision of a huge fibre-connected array of telescopes into a reality. We are very much looking forward to the new scientific results that will flow from the telescope over the coming years."
Professor John Womersley of the Science and Technology Facilities Council said:
"e-Merlin is a flagship project for the UK in radio astronomy, a scientific field where the UK has a rich legacy, a strong future, and is proud to be the home of some of the very best researchers in the world.
"The project has attracted more than 300 astronomers from over 100 institutes in more than 20 countries who will use the power of this 'super telescope' to conduct major scientific legacy projects."
Professor Mike Garrett, General Director of ASTRON, the Netherlands Institute for Radio Astronomy, said:
"e-MERLIN is going to be a transformational telescope - astronomers around the world can't wait to get their hands on it.
"As a pathfinder for the next-generation international radio telescope, the Square Kilometre Array, e-MERLIN represents another giant leap forward for the global radio astronomy community."
Animation
This animation begins with a wide-field HST view of the region around the double quasar. It zooms in to the double quasar and then the e-MERLIN radio image is superimposed. It then flies in to show a close-up view of the lower quasar image and the lensing galaxy, followed by the upper quasar image and the large-scale radio jet.
HD mp4 - Right click and download - NOTE this is a 30 Mb file.
WMV format large - Right click and download (2.3 Mb).
WMV format small - Right click and download (2.0 Mb).
Flash Video format (as above) - Right click and download (7.1 Mb).
Credit: Jodrell Bank Centre for Astrophysics, University of Manchester.
FURTHER INFORMATION
Additional quotes
Professor Steve Watts, Head of the University of Manchester's School of Physics & Astronomy, says:
"The development of this groundbreaking new telescope follows more than 60 years of radio astronomy research and development at Jodrell Bank Observatory. Our astronomers will be working closely with colleagues from around the world to make new scientific discoveries with e-MERLIN."
Professor Steve Rawlings of the University of Oxford says:
"This is a fantastic image. Nature provides us with gravitational lenses that help us study black holes across the Universe, but it is talented engineers and scientists that develop the technologies and instruments that allow us to exploit them. It's great for the UK that the e-MERLIN team are such world leaders in radio astronomy."
Dr Neal Jackson of the University of Manchester, an expert in gravitational lensing, says:
"This first image of the Double Quasar clearly demonstrates how useful e-MERLIN is going to be in our studies of gravitational lenses. By mapping the bending of light by mass we will be able to study the way in which both stars and dark matter are distributed in galaxies and how this changes as the universe evolves."
e-MERLIN
e-MERLIN is an array of seven radio telescopes across the UK whose signals are brought back on an optical fibre network to The University of Manchester's Jodrell Bank Observatory. Here they are combined in a highly-specialised supercomputer called a correlator (designed and constructed by the Dominion Radio Astrophysical Observatory of the National Research Council of Canada). The telescope array can then operate as a dedicated radio interferometer to produce high-resolution images. With a maximum baseline length of 220 km, e-MERLIN provides a unique capability for radio imaging with 0.01-0.15-arcsec resolution at wide bands around frequencies of 1.5, 5 and 22 GHz (L, C and K bands).
e-MERLIN is the UK's national facility for high resolution radio astronomy and is operated by The University of Manchester and the Science and Technology Facilities Council. Further information can be found on the e-MERLIN website (http://www.e-merlin.ac.uk).
The e-MERLIN upgrade has been funded by the Science and Technology Facilities Council (STFC), the Northwest Development Agency, The University of Manchester, The University of Cambridge and Liverpool John Moores University. It is being operated by STFC and the University of Manchester.
The Double Quasar
The "Double Quasar" is a gravitational lens - a famous confirmation of Albert Einstein's General Theory of Relativity showing that mass causes space to be curved. Here, this curvature causes the light and radio waves from a distant quasar to be bent around a foreground galaxy producing multiple images of the same quasar. The two brightest of these lensed images can be seen here as two bright objects, one below the other, separated by about 6 arcseconds.
The quasar itself is powered by a super-massive black hole leading to the ejection of jets of matter moving at almost the speed of light. The e-MERLIN image shows the bright radio emission from both the region around the black hole in the quasar images and also the jet arcing towards the left from the upper quasar image. This is the first time this whole jet has been imaged at such high (sub-kiloparsec) resolution. The elongation of the quasar core images is real - these are the inner jets close to the black hole as imaged at milli-arcsecond resolution in VLBI studies. The region where the counter jet, moving in the opposite direction to the bright radio jet, interacts with the intergalactic medium is also visible in this e-MERLIN radio image.
The length of the jet as it appears in this image is about 150,000 light years. However the jet is pointing towards us so its real length could be as much as five times longer. By comparison the diameter of the stellar disc of our own Milky Way galaxy is about 100,000 light years.
A somewhat smaller black hole also lies at the heart of the galaxy whose mass, together with its associated cluster of galaxies, is responsible for the lensing effect. The compact radio component just above the lower quasar image is thought to associated with the black hole in the foreground galaxy. In theory, the lensing effect will produce an odd number of images. However, the third image should be much fainter than the two brightest images and close to the lensing galaxy. One of the major e-MERLIN legacy programmes (led by Neal Jackson of The University of Manchester and Stephen Serjeant of The Open University) will take advantage of its unique combination of sharpness of view and sensitivity to faint emission to map the multiple images in gravitational lenses and thereby study the evolution of the distribution of mass in distant galaxies.
The Double Quasar, the first gravitational lens to be discovered, was found by Dr Denis Walsh of the University of Manchester during a radio survey of the northern sky using telescopes at Jodrell Bank. Follow-up work by Walsh and collaborators using an optical telescope at Kitt Peak in the USA, led to its identification as the first gravitational lens (see Walsh et al. 1979, Nature 279, 381). The quasar is at a redshift of 1.41 (a co-moving distance of about 13.7 billion light years) and is lensed by a bright galaxy (and associated cluster of galaxies) at a redshift of 0.355 (a co-moving distance of about 4.54 billion light years) forming a second image of the quasar core and inner jet.
This e-MERLIN image demonstrates the successful transmission of wide-bandwidth digitised signals from all the telescopes remote from Jodrell Bank over the optical fibre network. This initial image, made from a single hand of polarization with a bandwidth of 500 MHz centred on 6.5 GHz, has an angular resolution of 50 milli-arcseconds, similar to the resolution of the Hubble Space Telescope. The new system is already approaching 3 times the sensitivity of the previous radio-linked MERLIN telescope. The next steps are to add a second hand of polarization, increase the total bandwidth to 2 GHz per polarization and include the Lovell telescope. This will result in a very substantial (around a factor 5) further increase in sensitivity. Operations at full sensitivity are expected in 2011.
Contact
For media enquiries contact:
Dan CochlinMedia Relations
The University of Manchester
+44 (0)161 275 8387
daniel.cochlin@manchester.ac.uk
