UK students bring home gold from Astronomy Olympiad

Marlborough College Olympiad team smallerThe winning team from Marlborough College. Left to right: Chris Underhill, Alan Sun, Thomas Read, Michael Smith, Mavis Chan. Credit: S. Kruk. Click for a full size image.Five UK school students brought back medals from last month’s International Olympiad on Astronomy and Astrophysics. Led by Sandor Kruk (University of Oxford) and Charles Barclay (Marlborough College), the pupils travelled to Bhubaneswar, India, to compete alongside teams of school students from 40 other countries.

In a tough field, all five team members won awards. The team brought home one gold, one silver, and one bronze medal, and two team members received honourable mentions. This performance saw the UK placed sixth behind the Russian Federation, India, Iran, China and the USA. Thomas Read, the UK student who won the gold medal, was ranked 10th overall out of 200 participants.

The other contestants in the team were Michael Smith (who won silver), Alan Sun (bronze), Chris Underhill and Mavis Chan. Robin Hughes (Chairman of the British Physics Olympiad) acted as an observer.

Vera Rubin, 1928-2016

Pioneering astronomer Professor Vera Rubin, who carried out seminal research on the movement of stars in galaxies, died in December at the age of 88. Rubin, whose work added key evidence for the presence of dark matter, received the Gold Medal of the Royal Astronomical Society in 1996, the first woman to do so since Caroline Herschel in 1828.

Vera RubinVera Rubin in 2009. Credit: NASAProfessor John Zarnecki, President of the Royal Astronomical Society commented: “Vera Rubin made truly seminal discoveries in astronomy which inform the view of the Universe that we hold today. Her ideas were only fully accepted many years after they were first put forward partly because they were so ground breaking, and partly perhaps because she was at the time one of the very few female astronomers in what was a completely male dominated environment.

‘It was entirely fitting that the Royal Astronomical Society awarded her its Gold Medal, the Society’s highest honour.”

Christmas and new year closure

The RAS offices will be closed on the afternoon of Wednesday 21st December (from 12.30 pm) for staff to enjoy a festive celebration in the lead up to Christmas, and re-open on Thursday morning at 9.30 am.

The RAS Christmas tree 2014The RAS Christmas tree is adorned with crocheted planets, aliens and other astronomical objects. Click to enlarge.

 

The RAS offices will then close for Christmas and New Year from 12 noon on the afternoon of Friday 23 December 2016, and re-open at 9:30 am on Wednesday 4 January 2017.

 

Merry Christmas and a happy new year!

Dark Matter May be Smoother than Expected

Analysis of a giant new galaxy survey, made with the European Southern Observatory‘s VLT in Chile, suggests that dark matter may be less dense and more smoothly distributed throughout space than previously thought. An international team used data from the Kilo Degree Survey (KiDS) to study how the light from about 15 million distant galaxies was affected by the gravitational influence of matter on the largest scales in the Universe. The results appear to be in disagreement with earlier findings from the Planck satellite. The team publish their work in a paper in Monthly Notices of the Royal Astronomical Society.

eso1642a smallThis map of dark matter in the Universe was obtained from data from the KiDS survey, using the VLT Survey Telescope at ESO’s Paranal Observatory in Chile. It reveals an expansive web of dense (light) and empty (dark) regions. This image is one out of five patches of the sky observed by KiDS. Here the invisible dark matter is seen rendered in pink, covering an area of sky around 420 times the size of the full moon. This image reconstruction was made by analysing the light collected from over three million distant galaxies more than 6 billion light-years away. The observed galaxy images were warped by the gravitational pull of dark matter as the light travelled through the Universe. Some small dark regions, with sharp boundaries, appear in this image. They are the locations of bright stars and other nearby objects that get in the way of the observations of more distant galaxies and are hence masked out in these maps as no weak-lensing signal can be measured in these areas. Credit: Kilo-Degree Survey Collaboration/H. Hildebrandt & B. Giblin/ESO. Click for a full size image

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Hendrik Hildebrant from the Argelander-Institut für Astronomie in Bonn, Germany, and Massimo Viola from the Leiden Observatory in the Netherlands, led a team of astronomers from institutions around the world who processed images from the Kilo Degree Survey (KiDS), made with ESO’s VLT Survey Telescope (VST) at Paranal in Chile. For their analysis, they used images from the survey that covered five patches of the sky covering a total area of around 2200 times the size of the full Moon, and containing around 15 million galaxies.

By exploiting the exquisite image quality available to the VST at the Paranal site, and using innovative computer software, the team were able to carry out one of the most precise measurements ever made of an effect known as cosmic shear. This is a subtle variant of weak gravitational lensing, in which the light emitted from distant galaxies is slightly warped by the gravitational effect of large amounts of matter, such as galaxy clusters.

In cosmic shear, it is not galaxy clusters but large-scale structures in the Universe that warp the light, which produces an even smaller effect. Very wide and deep surveys, such as KiDS, are needed to ensure that the very weak cosmic shear signal is strong enough to be measured and can be used by astronomers to map the distribution of gravitating matter. This study takes in the largest total area of the sky to ever be mapped with this technique so far.

Intriguingly, the results of their analysis appear to be inconsistent with deductions from the results of the European Space Agency‘s Planck satellite, the leading space mission probing the fundamental properties of the Universe. In particular, the KiDS team’s measurement of how clumpy matter is throughout the Universe — a key cosmological parameter — is significantly lower than the value derived from the Planck data.

Massimo Viola explains: “This latest result indicates that dark matter in the cosmic web, which accounts for about one-quarter of the content of the Universe, is less clumpy than we previously believed.”

Despite making up about 85% of the matter in the Universe, dark matter remains elusive, and rather than being detected directly, its presence is only inferred from its gravitational effects. Studies like these are the best current way to determine the shape, scale and distribution of this invisible material.

The surprise result of this study also has implications for our wider understanding of the Universe, and how it has evolved during its almost 14-billion-year history. Such an apparent disagreement with previously established results from Planck means that astronomers may now have to reformulate their understanding of some fundamental aspects of the development of the Universe.

Hendrik Hildebrandt comments: “Our findings will help to refine our theoretical models of how the Universe has grown from its inception up to the present day.”

The KiDS analysis of data from the VST is an important step but future telescopes are expected to take even wider and deeper surveys of the sky.

The co-leader of the study, Catherine Heymans of the University of Edinburgh in the UK adds: “Unravelling what has happened since the Big Bang is a complex challenge, but by continuing to study the distant skies, we can build a picture of how our modern Universe has evolved.”

“We see an intriguing discrepancy with Planck cosmology at the moment. Future missions such as the Euclid satellite and the Large Synoptic Survey Telescope will allow us to repeat these measurements and better understand what the Universe is really telling us,” concludes Konrad Kuijken (Leiden Observatory, the Netherlands), who is principal investigator of the KiDS survey.

 


Media contacts

Richard Hook
ESO Public Information Officer
Garching bei Munchen, Germany
Tel: +49 89 3200 6655
Mob: +49 151 1537 3591
rhook@eso.org

Catriona Kelly
Press and PR Office
University of Edinburgh
Tel: +44 (0)131 651 4401
Mob: +44 (0)7791 355940
catriona.kelly@ed.ac.uk

 


Science contacts

Hendrik Hildebrandt
Head of Emmy Noether-Research Group
Bonn, Germany
Tel: +49 228 73 1772
hendrik@astro.uni-bonn.de

Massimo Viola
Leiden Observatory
Leiden, The Netherlands
Tel: +31 (0)71 527 8442
viola@strw.leidenuniv.nl

Catherine Heymans
Institute for Astronomy, University of Edinburgh
Edinburgh, United Kingdom
Tel: +44 131 668 8301
heymans@roe.ac.uk

Konrad Kuijken
Leiden Observatory
Leiden, The Netherlands
Tel: +31 715275848
Mob: +31 628956539
kuijken@strw.leidenuniv.nl

 


Further information

The international KiDS team of researchers includes scientists from Germany, the Netherlands, the UK, Australia, Italy, Malta and Canada.

The parameter measured is called S8. Its value is a combination of the size of density fluctuations in, and the average density of, a section of the Universe. Large fluctuations in lower density parts of the Universe have an effect similar to that of smaller fluctuations in denser regions and the two cannot be distinguished by observations of weak lensing. The ‘8’ refers to a cell size of 8 megaparsecs, which is used by convention in such studies.

This research is presented in the paper “KiDS-450: Cosmological parameter constraints from tomographic weak gravitational lensing“, by H. Hildebrandt et al., to appear in Monthly Notices of the Royal Astronomical Society.

The team is composed of H. Hildebrandt (Argelander-Institut für Astronomie, Bonn, Germany), M. Viola (Leiden Observatory, Leiden University, Leiden, the Netherlands), C. Heymans (Institute for Astronomy, University of Edinburgh, Edinburgh, UK), S. Joudaki (Centre for Astrophysics & Supercomputing, Swinburne University of Technology, Hawthorn, Australia), K. Kuijken (Leiden Observatory, Leiden University, Leiden, the Netherlands), C. Blake (Centre for Astrophysics & Supercomputing, Swinburne University of Technology, Hawthorn, Australia), T. Erben (Argelander-Institut für Astronomie, Bonn, Germany), B. Joachimi (University College London, London, UK), D Klaes (Argelander-Institut für Astronomie, Bonn, Germany), L. Miller (Department of Physics, University of Oxford, Oxford, UK), C.B. Morrison (Argelander-Institut für Astronomie, Bonn, Germany), R. Nakajima (Argelander-Institut für Astronomie, Bonn, Germany), G. Verdoes Kleijn (Kapteyn Astronomical Institute, University of Groningen, Groningen, the Netherlands), A. Amon (Institute for Astronomy, University of Edinburgh, Edinburgh, UK), A. Choi (Institute for Astronomy, University of Edinburgh, Edinburgh, UK), G. Covone (Department of Physics, University of Napoli Federico II, Napoli, Italy), J.T.A. de Jong (Leiden Observatory, Leiden University, Leiden, the Netherlands), A. Dvornik (Leiden Observatory, Leiden University, Leiden, the Netherlands), I. Fenech Conti (Institute of Space Sciences and Astronomy (ISSA), University of Malta, Msida, Malta; Department of Physics, University of Malta, Msida, Malta), A. Grado (INAF – Osservatorio Astronomico di Capodimonte, Napoli, Italy), J. Harnois-Déraps (Institute for Astronomy, University of Edinburgh, Edinburgh, UK; Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada), R. Herbonnet (Leiden Observatory, Leiden University, Leiden, the Netherlands), H. Hoekstra (Leiden Observatory, Leiden University, Leiden, the Netherlands), F. Köhlinger (Leiden Observatory, Leiden University, Leiden, the Netherlands), J. McFarland (Kapteyn Astronomical Institute, University of Groningen, Groningen, the Netherlands), A. Mead (Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada), J. Merten (Department of Physics, University of Oxford, Oxford, UK), N. Napolitano (INAF – Osservatorio Astronomico di Capodimonte, Napoli, Italy), J.A. Peacock (Institute for Astronomy, University of Edinburgh, Edinburgh, UK), M. Radovich (INAF – Osservatorio Astronomico di Padova, Padova, Italy), P. Schneider (Argelander-Institut für Astronomie, Bonn, Germany), P. Simon (Argelander-Institut für Astronomie, Bonn, Germany), E.A. Valentijn (Kapteyn Astronomical Institute, University of Groningen, Groningen, the Netherlands), J.L. van den Busch (Argelander-Institut für Astronomie, Bonn, Germany), E. van Uitert (University College London, London, UK) and L. van Waerbeke (Department of Physics and Astronomy, University of British Columbia, Vancouver, Canada).

 


Notes for editors

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Follow ESO on Twitter

The Royal Astronomical Society (RAS), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science. The RAS organizes scientific meetings, publishes international research and review journals, recognizes outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4000 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.

The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering. The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.

Follow the RAS on Twitter

Travel bursaries available for LGBT+ STEMinar

In addition to being a platinum sponsor for the second year running, the RAS is offering two travel bursaries of up to £100 for RAS Fellows that wish to attend the LGBT+ STEMinar at Sheffield University, but who may require some assistance with the costs of travel.

lgbtstem

Applicants will need to meet the following criteria:

Be registered to attend and/or be presenting at the conference
Be a Fellow of the RAS
Be a PhD student or First year Postdoc

Applications for the grant may be submitted at any time prior to the event. The successful grant applications will be considered in order of the date on which they are received, by email to outreach@ras.org.uk and successful applicants will be notified as soon as the claim is submitted. Payment will be made on completion of an expense claim and travel receipts following attendance at the event. The application form can be found docxhere.

For more information on this and on the LGBT+ Physicists and Astronomers Network please see: http://www.ras.org.uk/education-and-careers/for-everyone/2925-lgbt-physicists-and-astronomers-network.

First Signs of Weird Quantum Property of Empty Space?

By studying the light emitted from an extraordinarily dense and strongly magnetised neutron star using ESO’s Very Large Telescope, astronomers may have found the first observational indications of a strange quantum effect, first predicted in the 1930s. The polarisation of the observed light suggests that the empty space around the neutron star is subject to a quantum effect known as vacuum birefringence.

A team led by Roberto Mignani from INAF Milan (Italy) and from the University of Zielona Gora (Poland), used ESO’s Very Large Telescope (VLT) at the Paranal Observatory in Chile to observe the neutron star RX J1856.5-3754, about 400 light-years from Earth. They publish their results in a paper in Monthly Notices of the Royal Astronomical Society.

eso1641a smallThis artist’s view shows how the light coming from the surface of a strongly magnetic neutron star (left) becomes linearly polarised as it travels through the vacuum of space close to the star on its way to the observer on Earth (right). The polarisation of the observed light in the extremely strong magnetic field suggests that the empty space around the neutron star is subject to a quantum effect known as vacuum birefringence, a prediction of quantum electrodynamics (QED). This effect was predicted in the 1930s but has not been observed before. The magnetic and electric field directions of the light rays are shown by the red and blue lines. Model simulations by Roberto Taverna (University of Padua, Italy) and Denis Gonzalez Caniulef (UCL/MSSL, UK) show how these align along a preferred direction as the light passes through the region around the neutron star. As they become aligned the light becomes polarised, and this polarisation can be detected by sensitive instruments on Earth. Credit: ESO/L. Calçada. Click for a full size imageDespite being amongst the closest neutron stars, its extreme dimness meant the astronomers could only observe the star with visible light using the FORS2 instrument on the VLT, at the limits of current telescope technology.

Neutron stars are the very dense remnant cores of massive stars — at least 10 times more massive than our Sun — that have exploded as supernovae at the ends of their lives. They also have extreme magnetic fields, billions of times stronger than that of the Sun, which permeate their outer surface and surroundings.

These fields are so strong that they even affect the properties of the empty space around the star. Normally a vacuum is thought of as completely empty, and light can travel through it without being changed. But in quantum electrodynamics (QED), the quantum theory describing the interaction between photons and charged particles such as electrons, space is full of virtual particles that appear and vanish all the time. Very strong magnetic fields can modify this space so that it affects the polarisation of light passing through it.

Mignani explains: “According to QED, a highly magnetised vacuum behaves as a prism for the propagation of light, an effect known as vacuum birefringence.”

Among the many predictions of QED, however, vacuum birefringence so far lacked a direct experimental demonstration. Attempts to detect it in the laboratory have not yet succeeded in the 80 years since it was predicted in a paper by Werner Heisenberg (of uncertainty principle fame) and Hans Heinrich Euler.

“This effect can be detected only in the presence of enormously strong magnetic fields, such as those around neutron stars. This shows, once more, that neutron stars are invaluable laboratories in which to study the fundamental laws of nature.” says Roberto Turolla (University of Padua, Italy).

After careful analysis of the VLT data, Mignani and his team detected linear polarisation — at a significant degree of around 16% — that they say is likely due to the boosting effect of vacuum birefringence occurring in the area of empty space surrounding RX J1856.5-3754.

Vincenzo Testa (INAF, Rome, Italy) comments: “This is the faintest object for which polarisation has ever been measured. It required one of the largest and most efficient telescopes in the world, the VLT, and accurate data analysis techniques to enhance the signal from such a faint star.”

“The high linear polarisation that we measured with the VLT can’t be easily explained by our models unless the vacuum birefringence effects predicted by QED are included,” adds Mignani.

“This VLT study is the very first observational support for predictions of these kinds of QED effects arising in extremely strong magnetic fields,” remarks Silvia Zane (UCL/MSSL, UK).

Mignani is excited about further improvements to this area of study that could come about with more advanced telescopes: “Polarisation measurements with the next generation of telescopes, such as ESO’s European Extremely Large Telescope, could play a crucial role in testing QED predictions of vacuum birefringence effects around many more neutron stars.”

“This measurement, made for the first time now in visible light, also paves the way to similar measurements to be carried out at X-ray wavelengths,” adds Kinwah Wu (UCL/MSSL, UK).

 


Media contacts

Richard Hook
ESO Public Information Officer
Garching bei München, Germany
Tel: +49 89 3200 6655
Mob: +49 151 1537 3591
rhook@eso.org

 


Science contacts

Roberto Mignani
INAF – Istituto di Astrofisica Spaziale e Fisica Cosmica Milano
Milan, Italy
Tel: +39 02 23699 347
Mob: +39 328 9685465
mignani@iasf-milano.inaf.it

Vincenzo Testa
INAF – Osservatorio Astronomico di Roma
Monteporzio Catone, Italy
Tel: +39 06 9428 6482
vincenzo.testa@inaf.it

Roberto Turolla
University of Padova
Padova, Italy
Tel: +39-049-8277139
turolla@pd.infn.it

 


Further information

The research is presented in the paper entitled “Evidence for vacuum birefringence from the first optical polarimetry measurement of the isolated neutron star RX J1856.5−3754“, by R. Mignani et al., to appear in Monthly Notices of the Royal Astronomical Society.

The team is composed of R.P. Mignani (INAF – Istituto di Astrofisica Spaziale e Fisica Cosmica Milano, Milano, Italy; Janusz Gil Institute of Astronomy, University of Zielona Góra, Zielona Góra, Poland), V. Testa (INAF – Osservatorio Astronomico di Roma, Monteporzio, Italy), D. González Caniulef (Mullard Space Science Laboratory, University College London, UK), R. Taverna (Dipartimento di Fisica e Astronomia, Università di Padova, Padova, Italy), R. Turolla (Dipartimento di Fisica e Astronomia, Università di Padova, Padova, Italy; Mullard Space Science Laboratory, University College London, UK), S. Zane (Mullard Space Science Laboratory, University College London, UK) and K. Wu (Mullard Space Science Laboratory, University College London, UK).

ESO also has a full suite of multimedia resources for this release.

 


Notes for editors

ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

Follow ESO on Twitter

The Royal Astronomical Society (RAS), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science. The RAS organizes scientific meetings, publishes international research and review journals, recognizes outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4,000 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.

The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering. The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.

Follow the RAS on Twitter

Nominations for RAS Council close this Friday

Have you ever thought about becoming more involved with the RAS? The Society is run by a governing Council, which makes major strategic decisions on our future plans, as well as being the legally accountable body for our work. This year we’re seeking nominations for the positions of President-Elect (serving from May 2017, then President from 2018-20), two Vice-Presidents, a geophysics secretary, and four ‘ordinary’ members of Council. These positions are open to all Fellows, and if they are contested, as they usually are, elections will take place in the spring of 2017. Vice-Presidents serve for two years, the Geophysics Secretary serves for five years, and other members of Council have a three year term, all starting in May 2017.

 

Nominations close this Friday, 25 November. All Fellows should have received a nomination form and an associated letter setting out the duties of each role. If you’d like to know more, please contact the Burlington House office in the first instance, via membership@ras.org.uk.

Call for nominations: PhD thesis prizes

RAS logoEach year the RAS recognises the best PhD theses in astronomy and geophysics completed in the UK. The deadline to nominate theses completed during 2016 is 31 January 2017.

Three prizes are available: the Michael Penston prize for astronomy, the Keith Runcorn prize for geophysics, and the Patricia Tomkins prize for instrumentation science in either astronomy or geophysics. The winners receive £1000 and an invitation to present the results of their thesis at a meeting of the RAS. The Michael Penston prize and Keith Runcorn prize runners up will receive £50 book tokens. The Michael Penston and Keith Runcorn prizes are sponsored by Oxford University Press, who also publish the RAS journals.  The Patricia Tomkins prize is sponsored by the Patricia Tomkins Foundation.

Nominees must have completed their PhD (viva held and all corrections completed) at a UK university during 2016. For more details and to submit a nomination, see the pages on each prize:

  • Oxford University PressThe Michael Penston prize, for theses in astronomy and astrophysics, including cosmology, astrobiology etc.
  • The Keith Runcorn prize, for theses in geophysics, including seismology, solar physics, planetary science etc.
  • Patricia Tomkins thesis prize for theses in instrumentation science for astronomy and geophysics – while the support is aimed at developing skills in scientific hardware such as electronics, detectors and optics, the development of novel software specific to a hardware project will also be considered.

Australian desert telescope views sky in radio technicolour

A telescope located deep in the West Australian outback has shown what the Universe would look like if human eyes could see radio waves.

Published today in the Monthly Notices of the Royal Astronomical Society, the GaLactic and Extragalactic All-sky MWA, or ‘GLEAM’ survey, has produced a catalogue of 300,000 galaxies observed by the Murchison Widefield Array (MWA), a $50 million radio telescope located at a remote site north-east of Geraldton. 

GLEAM still 2 smallA ‘radio colour’ view of the sky above a ’tile’ of the Murchison Widefield Array radio telescope, located in outback Western Australia. The Milky Way is visible as a band across the sky and the dots beyond are some of the 300,000 galaxies observed by the telescope for the GLEAM survey. Red indicates the lowest frequencies, green the middle frequencies and blue the highest frequencies. Credit: Radio image by Natasha Hurley-Walker (ICRAR/Curtin) and the GLEAM Team. MWA tile and landscape by Dr John Goldsmith/Celestial Visions.

Lead author Dr Natasha Hurley-Walker, from Curtin University and the International Centre for Radio Astronomy Research (ICRAR), said this is the first radio survey to image the sky in such amazing technicolour. “The human eye sees by comparing brightness in three different primary colours – red, green and blue,” she said. “GLEAM does rather better than that, viewing the sky in each of 20 primary colours. That’s much better than we humans can manage, and it even beats the very best in the animal kingdom, the mantis shrimp, which can see 12 different primary colours.”

GLEAM is a large-scale, high-resolution survey of the radio sky observed at frequencies from 70 to 230 MHz, observing radio waves that have been travelling through space—some for billions of years.  “Our team are using this survey to find out what happens when clusters of galaxies collide,” Dr Hurley-Walker said. “We’re also able to see the remnants of explosions from the most ancient stars in our galaxy, and find the first and last gasps of supermassive black holes.”

MWA director Dr Randall Wayth said GLEAM is one of the biggest radio surveys of the sky ever assembled. “The area surveyed is enormous,” he said. “Large sky surveys like this are extremely valuable to scientists and they’re used across many areas of astrophysics, often in ways the original researchers could never have imagined.” 

Completing the GLEAM survey with the Murchison Widefield Array is a big step on the path to SKA-low, the low frequency part of the international Square Kilometre Array radio telescope to be built in Australia in the coming years. “It’s a significant achievement for the MWA telescope and the team of researchers that have worked on the GLEAM survey,” Dr Wayth said. “The survey gives us a glimpse of the Universe that SKA-low will be probing once it’s built. By mapping the sky in this way we can help fine-tune the design for the SKA and prepare for even deeper observations into the distant Universe.”

 

GLEAM-DataThe GLEAM view of the centre of the Milky Way, in radio colour. Red indicates the lowest frequencies, green the middle frequencies and blue the highest frequencies. Each dot is a galaxy, with around 300,000 radio galaxies observed as part of the GLEAM survey. Credit: Natasha Hurley-Walker (ICRAR/Curtin) and the GLEAM Team.


 

Media contacts

 

Pete Wheeler

ICRAR

Tel: +61 423 982 018                       

pete.wheeler@icrar.org

 

Dr Robert Massey

Royal Astronomical Society

Tel: +44 (0)20 7734 3307

rm@ras.org.uk

 


 

Science contacts

 

Dr Natasha Hurley-Walker

Curtin University, ICRAR

Tel: +61 426 192 677                       

nhw@icrar.org

 

Dr Randall Wayth

Curtin University, ICRAR, CAASTRO

Tel: +61 418 282 359                       

randall.wayth@icrar.org

 


 

Images and Captions

 

http://s3-ap-southeast-2.amazonaws.com/icrar.org/wp-content/uploads/2016/10/20135903/GLEAM_still_2_small.jpg
A ‘radio colour’ view of the sky above a ’tile’ of the Murchison Widefield Array radio telescope, located in outback Western Australia. The Milky Way is visible as a band across the sky and the dots beyond are some of the 300,000 galaxies observed by the telescope for the GLEAM survey. Red indicates the lowest frequencies, green the middle frequencies and blue the highest frequencies. Credit: Radio image by Natasha Hurley-Walker (ICRAR/Curtin) and the GLEAM Team. MWA tile and landscape by Dr John Goldsmith/Celestial Visions.

 

http://s3-ap-southeast-2.amazonaws.com/icrar.org/wp-content/uploads/2016/10/20135801/GLEAM-Data.jpg

The GLEAM view of the centre of the Milky Way, in radio colour. Red indicates the lowest frequencies, green the middle frequencies and blue the highest frequencies. Each dot is a galaxy, with around 300,000 radio galaxies observed as part of the GLEAM survey. Credit: Natasha Hurley-Walker (ICRAR/Curtin) and the GLEAM Team.

 


 

Further information

 

High-resolution videos and images are available from www.icrar.org/GLEAM 

Original publication, ‘GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) survey I: A low-frequency extragalactic catalogue’, published in the Monthly Notices of the Royal Astronomical Society onOctober 27th, 2016. Available from http://s3-ap-southeast-2.amazonaws.com/icrar.org/wp-content/uploads/2016/10/18223055/GLEAM-Paper_sml.pdf

 


 

Notes for editors

 

The Murchison Widefield Array (MWA) is a low frequency radio telescope located at the Murchison Radio-astronomy Observatory in Western Australia’s Mid West. The MWA observes radio waves with frequencies between 70 and 320 MHz and was the first of the three Square Kilometre Array (SKA) precursors to be completed. A consortium of 13 partner institutions from four countries (Australia, USA, India and New Zealand) has financed the development, construction, commissioning and operations of the facility. Since commencing operations in mid 2013 the consortium has grown to include new partners from Canada and Japan. Key science for the MWA ranges from the search for redshifted HI signals from the Epoch of Reionisation to wide-field searches for transient and variable objects (including pulsars and Fast Radio Bursts), wide-field Galactic and extra-galactic surveys, and solar and heliospheric science.

 

The Square Kilometre Array (SKA) project is an international effort to build the world’s largest radio telescope, led by SKA Organisation based at the Jodrell Bank Observatory near Manchester. Co-located primarily in South Africa and Western Australia, the SKA will be a collection of hundreds of thousands of radio antennas with a combined collecting area equivalent to approximately one million square metres, or one square kilometre. The SKA will conduct transformational science to improve our understanding of the Universe and the laws of fundamental physics, monitoring the sky in unprecedented detail and mapping it hundreds of times faster than any current facility.

 

The International Centre for Radio Astronomy Research (ICRAR) is a joint venture between Curtin University and The University of Western Australia with support and funding from the State Government of Western Australia.

 

The Royal Astronomical Society (RAS,www.ras.org.uk), founded in 1820, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science. The RAS organizes scientific meetings, publishes international research and review journals, recognizes outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally. Its more than 4000 members (Fellows), a third based overseas, include scientific researchers in universities, observatories and laboratories as well as historians of astronomy and others.

The RAS accepts papers for its journals based on the principle of peer review, in which fellow experts on the editorial boards accept the paper as worth considering.  The Society issues press releases based on a similar principle, but the organisations and scientists concerned have overall responsibility for their content.

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