Thursday, December 8, 2011

LOFAR on the Map of GPU Computing.

Of possible interest to those involved in LOFAR is this map of the GPU (Graphical Processing Unit) computing usage for research. The LOFAR Epoch of Reionization Key Science project makes it onto the map in Groningen where GPUs are being used for signal and image processing of the data generated by LOFAR for this experiment.  

Friday, December 2, 2011

LOFAR Session at NAM 2012

The UK National Astronomy Meeting, to be held in Manchester in March 2012 will host a session on "LOFAR, the LOw Frequency ARray: Ongoing Developments and Early Results" preliminarily scheduled for 10am on Thursday 29th March 2012.

This session will be run by LOFAR scientists, Mario M. Bisi (Institute of Mathematics and Physics, Aberystwyth University, UK), Michael W. Wise (Astronomy Group, ASTRON (Netherlands Institute for Radio Astronomy), The Netherlands), Philip Best (School of Physics and Astronomy, University of Edinburgh, UK), Benjamin W. Stappers (The School of Physics and Astronomy, The University of Manchester, UK), Peter T. Gallagher (School of Physics, Trinity College Dublin, Ireland), and and Marcus Braggen (School of Engineering & Science, Jacobs University, Germany), the session has the following abstract:

"The LOw Frequency ARray (LOFAR) is a next-generation radio telescope which utilises thousands of stationary dipoles and tiles to observe celestial phenomena. This session is intended for the broader community to learn about the developments of LOFAR including updates on the status of the system and its current scientific capabilities, the early science results from all aspects of its applications and operation, as well as the upcoming opportunities for general "open skies" observing.With its dense core array and interferometric baselines of up to 1,000 km, LOFAR has the potential to achieve both unparalleled sensitivity (sub-mJy) and spatial resolution (sub-arcsecond) in this largely-unexplored low-frequency radio regime (~10 MHz to 250 MHz). Areas of science which can be explored with LOFAR include, but are not limited to, the Epoch of Re-ionisation (EoR), Pulsars, Transients, Cosmic Rays, Magnetism, deep Extra-Galactic Surveys, and also studies of the Sun, the Solar Atmosphere/Solar Wind, Space Weather, and the Earth's Ionosphere. In summary, the session is designed for showcasing LOFAR's scientific potential and progress to date. The session should include a LOFAR overview and specifics of LOFAR commissioning, current status, scientific and technical capabilities, and upcoming opportunities. We solicit contributions from any/all of the science areas that will be covered by the observational capabilities of LOFAR."

Monday, November 14, 2011

Spectacular view of the LOFAR Core

Check out this ASTRON image of the day from last month with spectacular aerial images of the LOFAR core region.

ASTRON image of the day from 12th Oct 2010. Please visit the link for more details. 

Friday, November 11, 2011

Everyone's Favourite Image of Chilbolton - reflected in the sunglasses

I constantly get asked for this image, so here's a post just about it. Chilbolton reflected in the sunglasses of ICG member Dr. Edd Edmondson as photographed by former ICG member Dr. Chiara Tonini.

Album of all of Chiara's pictures from the LBA installaton.

Wednesday, November 9, 2011

Tonight at Intech - LOFAR-UK Talk

You can have the chance to hear all about LOFAR, and the installation and running of the UK LOFAR station in Chilbolton in person soon. Our LOFAR-UK station manager, Derek McKay-Bukowski will speak about

"Digital Static: Hampshire's new world-class radio telescope" this evening as part of the Intech Science Centre's Space Lecture Series.

Tickets are still available according to @INTECH_Science this morning.

Monday, October 3, 2011

LOFAR-UK Observes the Active Sun

Over the last few days, our Sun has been very active. Apart from the dedicated solar instruments monitoring this activity, we've also been able to observe it with the LOFAR radio telescope at Chilbolton. This facility comprises two fields of small antennas, that link together to perform as a powerful VHF radio telescope. Although it is also possible to link the LOFAR system in the UK with others across Europe, on the 28th September 2011, it was operating independently.

All Sky Image taken from LOFAR-UK, 28.09.11 (Credit: ASTRON/STFC)

At 16:10 UTC (= 5:10 pm local time), LOFAR Chilbolton was used to record an 'all-sky' image. Even before calibration and analysis, this image shows the bright objects in the radio sky. On the left hand side of the image there are, from top to bottom, Cassiopeia-A (a supernova remnant), Cygnus-A (a radio-galaxy) and the broader region which is the centre of our own Galaxy. However, to the right of the image, the Sun can be seen with extremely strong intensity, just before it set below the western horizon.

Menno Norden (ASTRON) and Derek McKay-Bukowski (RAL Space)

(Press release from RAL; KAIRA blog post.). 

Tuesday, September 20, 2011

Welcome to Swedish LOFAR; making LOFAR even bigger

The Swedish LOFAR station in Onsala is to be opened on Monday, joining stations all over Europe to make the International LOFAR Telescope even bigger. Below is the press release from Onsala Space Observatory.

Swedes Make World's Largest Telescope Bigger

The 192 radio antennas that make up Onsala’s Lofar station cover an area the size of a soccer pitch. Credit: Onsala Space Observatory/Leif Helldner

On Monday, Sweden’s Minister for Education and Research, Jan Björklund, will open Onsala Space Observatory’s newest telescope. Part of LOFAR, the world’s largest radio telescope, it is the biggest telescope built in Sweden in the last 35 years. LOFAR will map radio signals which have travelled across the universe for billions of years. Scientists expect LOFAR to answer questions about the nature of our universe.

LOFAR (LOw Frequency ARray) is a new kind of radio telescope. It can see radio waves with low frequencies, similar to those that give us FM radio. Rather than collecting signals from individual radio sources, LOFAR continuously monitors large swathes of sky. Lofar is more sensitive to the longest observable radio waves than any other telescope. It can see many billions of light years out into space, back to the time before the first stars formed, a few hundred million years after the Big Bang.

The 192 new radio antennas at Onsala’s LOFAR station look modest enough. But the radio signals they collect will be linked together with 47 similar stations over the whole of Europe, and sent over Internet to a central supercomputer in the Netherlands. This means huge amount of data traffic: the equivalent of over 7000 DVD films per day just from the Swedish station. The telescope creates images of the sky using a unique combination of computer power and innovative software. Together, LOFAR’s antennas form a single telescope with a diameter of 1300 kilometres.

Hans Olofsson is director of Onsala Space Observatory and professor at Chalmers.

“For astronomers like me, LOFAR means that we can see far enough to be able to study the universe’s early history. We want to discover traces of the clouds of hydrogen gas that filled the universe 13 billion years ago, and find out just why today’s universe looks the way it does,” he says.

Scientists expect LOFAR to discover hitherto unknown types of astronomical objects. It will also investigate the environments of black holes, find extreme galaxies and pulsars, and search for planets around other stars.

Onsala Space Observatory was founded in 1949 and was led for three decades by Professor Olof Rydbeck. Since its inception the observatory has contributed to the forefront of research in radio astronomy, both through interpretation of observations and developing new technology. Since 1990 the observatory is the Swedish National Facility for Radio Astronomy. It is financed by the Swedish Research Council and operated by Chalmers.

“Onsala Space Observatory has always been a prominent centre for radio astronomy research, and now it’s part of the world’s most exciting radio telescope. In the future we plan to develop the technology that makes Lofar unique when we build the next generation of radio telescopes, says René Vermeulen of Astron, the Netherlands national institute for radio astronomy, and director of the International LOFAR Telescope.

LOFAR is one of many examples of Onsala Space Observatory’s increasing involvement in international projects. Chalmers is one of three international partners in the submillimetre telescope Apex in Chile, which recently discovered hydrogen peroxide in space. Last winter Chalmers delivered sensitive new receivers to the Alma Observatory, the world’s largest astronomy project, currently being built in Chile’s Atacama desert. The observatory is also planning for the radio observatory SKA (Square Kilometre Array), to be built in Australia or South Africa, in which LOFAR’s new technology will be developed even further. SKA is expected to give answers about the origins of both the universe itself and life in space.

“Space research is also critical for our understanding of the earth and its climate, and it invariably leads to spin-off effects. International facilities like Lofar foster strong cooperation across both scientific and cultural borders,” says Karin Markides, President of Chalmers.

“I believe LOFAR in particular will have great importance for our ability to handle very large amounts of data,” she adds.

During the inauguration ceremony at Onsala Space Observatory on Monday Minister of Education and Research Jan Björklund will take some of the first ever images of the sky with the Swedish LOFAR station. He will also visit the station together with around a hundred invited guests.

For more information see here. 

Thursday, September 1, 2011

LOFAR-UK Data School in Manchester

The LOFAR-UK data school is currently in progress in Manchester. You can see the programme and download some of the talk on the school website

Data school participants pose for a photo.

Hard at work learning about long baseline interferometry.

Monday, August 22, 2011

Alan Penny - We should talk about Aliens

In an article for the Guardian Science Blog, LOFAR-UK member Dr. Alan Penny from the University of St. Andrews, argues that we should think more about what to say to aliens if we ever do detect them.

"We Need to Talk about Aliens"

Alan is leading efforts to run test SETI observations using the LOFAR-UK station in stand-alone mode (ie. not connected to the rest of the LOFAR array).

LOFAR at the BAA Radio Astronomy Group 2011 General Meeting

At the 2011 General Meeting of the British Astronomical Association's Radio Astronomy Group (to be held 12th November 2011 at the Humfrey Rooms, Castilian Terrace, Northampton), the two keynote speakers have a LOFAR-UK link. They are Professor Paul Alexander, who is Head of the Astrophysics Group at Cambridge is the project leader for the UK contribution to the Square Kilometre Array (and a member of LOFAR-UK), and Dr Ben Stappers from Jodrell Bank who is Head of the Pulsar Science Working Group for the LOFAR radio telescope (and Technical Co-ordinator for LOFAR-UK). 

For more details see the BAA Radio Group website

Wednesday, August 17, 2011

Portsmouth College Work Experience Student Makes LOFAR-UK Poster

Last week at ICG, Portsmouth we hosted a local A-level student from Portsmouth College who made the below LOFAR-UK poster. We hope to use this poster locally in Hampshire to advertise the world class radio telescope on our doorstep.

Monday, August 8, 2011

Solar and Space Weather KSP Meeting

Members of the Solar and Space Weather Key Science Project for LOFAR met for a workshop in Aberystwyth on the west coast of Wales at the end of June.  The Workshop focused on the progress achieved so far in using LOFAR to obtain images of the solar corona, using the dynamic spectrum (2D plots of time versus frequency) to identify and mitigate interference and obtain measurements of interplanetary scintillation (the scintillation of radio sources due to density variations in the solar wind).  Results so far look encouraging and compare favourably with similar measurements taken on traditional instruments but much work remains to be done.  Participants also had time to enjoy the environs of Aberystwyth and it's various pubs and restaurants!

(with thanks to Richard Fallows for this report). 

Friday, August 5, 2011

LOFAR related postdocs at CEA Saclay (near Paris)

Another job advert for two postdoc positions at CEA Saclay near Paris working on detection of radio transients - including for the LOFAR Transient Key Project.

AAS Job Register posting (copied below).

Applications are invited for two postdoctoral positions in signal processing/data analysis for an initial period of 2 years, with the UnivEarthsS LabEx program.
The astrophysics division of CEA Saclay is offering two positions to work with Professor Stéphane Corbel on radio transients in close collaboration with Jean-Luc Starck. Over the next decade, a combination of increased sensitivity, larger field of view, and algorithmic developments will open up the time domain to a wide range of astronomical fields, from stellar flares and supernovae to neutron-star and black-hole births, quakes and instabilities. Radio astronomy is leading this effort and transient science is identified as a key goal for LOFAR (Europe), ASKAP (Autralia) and MeerKAT (South Africa), the precursor instruments of the major international SKA facility to be developed for 2020+.
The applicant will work in one of these related topics:
  -Transient search in one of the affiliated key projects: TKP (LOFAR), ThunderKAT (MeerKAT), VAST (ASKAP),
  - Optimization of current methods and development of near real-time detection pipelines,
  - Characterization of transients and identification at other wavelengths,
  - Image reconstruction from undersampled Fourier measurements.
Minimum qualifications include an undergraduate degree or higher in astronomy, physics, computer science, statistics or related field. The candidate must have a strong motivation in developing statistical methods and applying them in large international projects. CEA Saclay ( ) is located 25km south of Paris, near Universities and other research centers. The astrophysics division gathers more than 150 faculty and staff members, studying a large range of astrophysical problems.
The positions are initially for two years and the starting dates should be between early Fall 2011 and early 2012. Ample funding for conferences, collaborations, personal equipment and publication is available. Applicants should submit by email resume, bibliography and a brief research plans to Stéphane Corbel ( and Jean-Luc Starck ( and arrange for three reference letters to be sent as well before 31 August 2011.

LOFAR to be subject of an RAS Public Lecture

LOFAR is to be the subject of an upcoming Public Lectures hosted by the Royal Astronomical Society, on 10th January 2012.

The talk, LOFAR: A Radio Telescope the Size of Northern Europe will be given by LOFAR-UK and Transients Key Project member Dr. Edward Daws from the University of Sheffield.

RAS Pubic Lectures are 45-minute lunchtime talks for non-specialists. Members of the public can listen to leading scientists talk about their work.
Place: Lecture Theatre, Royal Astronomical Society, Burlington House, Piccadilly, London.
Time: 1pm, second Tuesday of the month.

'Friends of the RAS' are encouraged to reserve a seat, subject to availability, by email (to ) or letter up until 10am on the day of the lecture. Seats, in the reserved area of the lecture theatre, will be kept until 1255 (when they will be released). Simply turn up before 1255 – but please do sit in the reserved, central, rows!

Seats cannot be guaranteed for ‘Friends’ who do not reserve them. However, subject to availability, they will be admitted into the non-reserved seating area or the Council Room (where the lecture will be relayed on a plasma screen). To improve your chance of a seat in the lecture theatre you should arrive before 1245.

After 1245 ‘non-Friends’ will be admitted, subject to availability, to the  non-reserved seating area or the Council Room. Before 1245 ‘non-Friends’ will be held in a queue outside the building. Please note advance seat reservation is restricted to 'Friends'.

Summaries of (some) previous lectures can be read on the 'Friends of the RAS' web site

For further information call 020 7734 3307 / 4582

Wednesday, July 27, 2011

Postdoc position in LOFAR long-baseline development and implementation (Bonn)

Another LOFAR related postdoc position advertised this week - this one in Bonn. Text below taken direct from the job advert.

Postdoc position in LOFAR long-baseline development and implementation (Bonn)

LOFAR is an innovative, low-frequency, multi-station aperture array telescope that is using new technologies and novel software approaches. LOFAR has entered its commissioning phase and started producing unique data in the relatively unexplored spectral window below 200 MHz.

The Argelander-Institute for Astronomy at the University of Bonn is offering a (max.) three-year postdoc/software developer position for long-baseline calibration development and implementation to start as soon as possible. The international baselines of LOFAR require special calibration schemes that are not fully included in the general calibration pipeline, yet. Sophisticated fringe-fitting methods that take into account the special polarisation properties of the system have to be developed for this purpose. Current algorithms have to be extended and added to the calibration pipeline.
Long-baseline commissioning is continuously making progress,


Contributing to these efforts will be part of the project. Despite the emphasis of technical development work, unique science projects will be possible as well. Particularly the long baselines of LOFAR are probing an entirely new parameter space with many important discoveries to be expected. LOFAR has already improved the resolution of low-frequency VLBI imaging by an order of magnitude. Appointees are expected to spend 50% of their time on astronomical research (which would preferably be related to LOFAR) and 50% on development work.

Relevant qualifications are experience in radio interferometry beyond the bare user level, particularly on very long baselines, a mathematical understanding of the methods involved, and programming expertise. This experience should generally be proven by a PhD in astronomy, physics or another relevant field, even though a Master's degree may be sufficient in particular cases. The ability to work independently but in cooperation with an international team of astronomers and developers, as well as excellent communication skills and a good command of the English language are essential.

Applications (preferably by email) should include a CV, a statement of interests and experience, the prefered starting date, and three letters of reference. Applicants of any nationality are eligible to apply. The University of Bonn is an equal opportunities employer. Deadline for full consideration is 15 October 2011. Applications may still be accepted until the position is filled.

The remuneration is based on a public pay scale (generally TV-L/E13) and subject to age and experience. Comprehensive benefits include paid vacation, sick leave, parental leave, and social security benefits (contributions to unemployment and health insurance as well as retirement scheme).

This project is part of wider LOFAR efforts by a consortium of astronomical institutes in Germany. Positions in other fields (to be announced on the AAS job register in September) are available as well. Applicants who would like to have their application considered also for other locations should state this in the cover letter.

More information is available on request.

Dr. Olaf Wucknitz
Argelander-Institute for Astronomy
Auf dem Huegel 71
53121 Bonn


Monday, July 25, 2011

LOFAR related Postdoc Position at ICG, Portsmouth

The University of Portsmouth's Institute of Cosmology and Gravitation (ICG) is advertising a postdoctoral position for
Development of software to incorporate the international baselines of the Low Frequency Array (LOFAR) into the LOFAR core array pipeline and data reduction framework. 
For more details see the job advert.

Wednesday, July 6, 2011

Blogging about installing a LOFAR Station

From the hit counts last summer we know that the reports here describing the installation of the LOFAR station at Chilbolton were very popular. If you miss those posts  you have two options

(1) revisit them using the tag installation

(2) relive this experience with a different station this summer as the KAIRA blog reports on the installation of the LOFAR station in Finland (also follow @KairaProject and @EISCAT_3D on Twitter for updates).

Edited to add option (3) which is to look at the pictures/blog posts about the installation of Swedish LOFARTack så mycket to Swedish LOFAR Tweeters @OnsalaRymd for reminding me about that.

Tuesday, July 5, 2011

LOFAR-UK Data School

The 76-m Lovell Telescope at Jodrell Bank
Credit: A.Holloway, University of Manchester
LOFAR-UK is organising a LOFAR data school, which will take place from 30 August-1 September 2011 at the Jodrell Bank Centre for Astrophysics, located in the Alan Turing Building, University of Manchester.

The aim of the data school is to introduce interested astronomers to the techniques that are needed to interact successfully with LOFAR data, especially those from long baselines. Due to venue capacity, numbers will be limited to 25, on a first-come, first-served basis. Registration is free for participants from any LOFAR-UK institution; for others a small charge of 50 pounds will be made for provision of coffee/tea and lunches during the meeting.

For more information, and to register for the meeting, please see

Monday, July 4, 2011

First Science with LOFAR

In September, ASTRON are hosting a workshop on "First Science from LOFAR". Scientists interested in attending should visit the workshop website.

Friday, July 1, 2011

LOFAR-UK Becomes a Full Member of the International LOFAR Telescope

At a recent meeting of the management of the Internatonal LOFAR Telescope, LOFAR-UK and STFC  signed the contract which governs the running the Chilbolton LOFAR Station (UK608) for 5 years and the transfer of data to The Netherlands for use in ILT array wide observations. 

Following this, and other similar contracts signed by the other international partners in the ILT (France, Germany and Sweden), all four international partners in LOFAR were formally welcomed as full members of the ILT, and given commemorative certificates. 

This is a significant milestone for LOFAR-UK guaranteeing UK scientists access to the agreed upon fraction of LOFAR data and many congratulations are due to the management of LOFAR-UK for the completion of this stage of the project.

From left to right shown are: FLOW representative Michel Tagger, GLOW delegate to the meeting Anton Zensus, LOFAR-Sweden secretary John Conway, LOFAR-UK chairman Philip Best, NL-LAC delegate and ILT Board chairman Heino Falcke, ILT Director Rene Vemeulen, ASTRON delegate Mike Garrett, and NL-LAC delegate Ralph Wijers.

The above picture, from the ASTRON picture of the day for June 30th shows members of the board celebrating this event.

 The LOFAR stations provided by these international partners greatly improve the capabilities of the ILT, by extending the maximum baseline of the telescope and therefore increasing resolution significantly (as was demonstrated by the first light image including 3 international stations). 

 Further countries are continuing to work towards obtaining funding 
for LOFAR stations and will hopefully join in the future extending the capabilities of the telescope even further. 

Thursday, June 23, 2011

Hear about LOFAR from the UK Station Manager

You can have the chance to hear all about LOFAR, and the installation and running of the UK LOFAR station in Chilbolton in person soon. Our LOFAR-UK station manager, Derek McKay-Bukowski will speak about

"Digital Static: Hampshire's new world-class radio telescope" on 9th November this year as part of the Intech Science Centre's Space Lecture Series. Book early to avoid disappointment.

Wednesday, June 15, 2011

Wide Area Surveys with LOFAR (and other radio telescopes)

LOFAR-UK member, Dr. Matt Jarvis (Hertfordshire, Surveys KSP) spoke yesterday at the Very Wide Area Surveys conference being held this week at the Space Science Telescope Institute (STSci - those are the people who run the Hubble Space Telescope among other things) in Baltimore, MA, USA. He talked about the plans for radio continuum surveys over large areas of the sky which are planned with both LOFAR and other future radio telescopes.

The talk was webcast, and can be watched on the STSci Webcast Site, as well as below.

Monday, June 13, 2011

Solar and Space Weather KSP Workshop 2011

The 5th Solar and Space Weather KSP Workshop is to be held in Aberystwyth later this month.

Visit the website for more details.

Thursday, June 9, 2011

Talking about LOFAR on the Astronomy Now YouTube Channel

At NAM in Llandudno I talked with Nick Howes from Astronomy Now about the LOFAR project. The video was posted on the Astronomy Now YouTube Channel this week.

Wednesday, June 1, 2011

LOFAR Makes Deeper Images of the Universe than ever before

The below press release was posted at ASTRON today describing some very deep images taken by LOFAR as part of the commissioning for the Epoch of Reionization project (the part of LOFAR which is trying to look for evidence of the first stars turning on).

See the press release on the ASTRON website (copied below).

LOFAR makes deeper images of Universe than ever before

An international team led by astronomers at ASTRON and the Kapteyn Institute of the University of Groningen have used the LOFAR telescope, designed and constructed by ASTRON, to make the deepest wide-field images of the sky in the relatively unexplored part of the spectrum around 150 MHz. It reveals faint radio sources never seen before.

3C196-Sarod: A tiny part of the LOFAR image of the field centered 
on the North Celestial Pole. It shows at least 7 discrete sources, some 
of them double or complex. The faintest source has a flux density of only
 a few mJy at 150 MHz.  The image has an angular resolution of 8 arcseconds 
but still needs to be deconvolved. The data was processed by Dr. Sarod Yatawatta 
on the EoR-cluster at the University of Groningen
The results were presented at an international conference in Zadar, Croatia, last week (May 23-27, see and were eagerly awaited by the astronomical community. The Zadar conference (organised by team member dr. V. Jelic, ASTRON), discussed the properties of the foregrounds that trouble our view of the distant Universe. Two projects were central at the conference: Planck observations of the Cosmic Microwave Background and (searches for) redshifted 21cm line observations of an era known as the Epoch of Reionization (EoR). This phase in the Universe is believed to have taken place in the period between about 400 and 800 million years after the Big Bang. The birth of the Universe took place about 13.8 billion years ago. During the EoR the neutral hydrogen was slowly disappearing, probably as a result of the strong 'ionizing' power of the first stars and quasars. Detecting the EoR is one of the hottest projects in astronomy today.

A group of astronomers based at ASTRON and the Kapteyn Institute of the University of Groningen, headed by Prof. Ger de Bruyn, Dr. Michiel Brentjens, Prof. Leon Koopmans and Prof. Saleem Zaroubi, is in the race to first detect these signals. They lead a team of about a dozen members, including astronomers currently working in Germany, USA, Canada and Sweden (see http:/ The results presented at the conference constitute an important step on the road to detecting the elusive signals. However, there is still a long way to go along this road.

Most of the antenna stations of the International LOFAR Telescope have already been rolled out across the Netherlands and Europe. It has been taking data for a large number of astronomers after its official opening by Her Majesty queen Beatrix of the Netherlands last year. The LOFAR data on which the images are based, were obtained in a 6-hour synthesis on the night of 29/30 January 2011 and the evening of 1 April 2011 using 18 core stations and 7 remote stations. Signals were recorded with the High Band Antennas and covered the frequency range from 115 - 163 MHz. After initial processing on the central LOFAR cluster they were transferred and further processed on a cluster dedicated to the processing of data for the LOFAR Epoch-of-Reionization project. This cluster is also located at the Computing Centre of the University of Groningen.
Cutouts from a very small part of the giant images are shown in the associated figures. One of the fields is centered at the celestial North Pole which is special in the sense that night-time observations can be obtained all year round. The second field was centered at the bright compact quasar 3C196 in the constellation of Lynx. The images, which have a resolution of 8" are already comparable to, or even slightly better, than the best published images taken with the Giant Meter Wavelength Radio telescope (GMRT) in India. The images contain a large number (>1000) of both very bright and very faint sources, spanning a so-called dynamic range of more than 200,000:1 in brightness between sources in the 3C196 image.

3C196-Panos: A very small part of the raw LOFAR image of the field centered 
on the bright quasar 3C196. It  shows tens of discrete sources, the faintest having 
a flux density of only a few mJy at 150 MHz. The image has an angular resolution 
of 8 arcseconds.  The image still needs to be deconvolved. The data was processed 
by Dr. Panos Labropoulos on the EoR-cluster at the University of Groningen.

This is an important record for the time being for LOFAR. The image quality, however, is still not perfect and significant improvements can be expected in the months ahead using improved knowledge of the effects of the LOFAR station beams. Continued efforts are also needed to improve the software to deal with imaging artefacts and the ionosphere. These two fields and several others will be observed for about 100 nights to conclusively detect signals from the EoR.
The results, and their implications, will soon be written up in two papers headed by Dr. Panos Labropoulos (ASTRON) and Dr. Sarod Yatawatta (ASTRON/ RuG) who lead the processing of the datasets for the 3C196 and NCP fields, respectively.

End of press release

For more information, please contact:
Prof. Ger de Bruyn, senior astronomer. Phone: +31 521 595 787. E-mail:
Dr. Michiel Brentjens, support scientist. Phone: +31 521 595 781. E-mail:

University of Groningen:
Prof. Leon Koopmans, astronomer. Phone: + 31 50 363 6519. E-mail:

Captions to the images:
3C196-Panos: A very small part of the raw LOFAR image of the field centered on the bright quasar 3C196. It  shows tens of discrete sources, the faintest having a flux density of only a few mJy at 150 MHz.The image has an angular resolution of 8 arcseconds.  The image still needs to be deconvolved. The data was processed by Dr. Panos Labropoulos on the EoR-cluster at the University of Groningen.

3C196-Sarod: A tiny part of the LOFAR image of the field centered on the North Celestial Pole. It shows at least 7 discrete sources, some of them double or complex. The faintest source has a flux density of only  a few mJy at 150 MHz.  The image has an angular resolution of 8 arcseconds but still needs to be deconvolved. The data was processed by Dr. Sarod Yatawatta on the EoR-cluster at the University of Groningen
The data were obtained as part of the commissioning of LOFAR and the results obtained thus far are a tribute to the hard work of a large group of people, usually referred to as the LOFAR collaboration.  

About LOFAR:
The International LOFAR telescope is a Pan-European collaborative project led by ASTRON Netherlands Institute for Radio Astronomy. Combining thousands of simple dipole receivers with powerful digital signal processing and high-performance computing, LOFAR can rapidly survey wide areas of the sky, looking in multiple directions simultaneously and relatively unexplored low frequencies, opening open up a new window for astronomers.

LOFAR will focus on six areas of research:

1. The Epoch of Reionisation - understanding how the first stars and black holes made the universe hot.
2. Extragalactic surveys - what is the history of star formation and black hole growth over cosmological time?
3. Transients and Pulsars - probing the extreme astrophysical environments that lead to transient bright bursts in the radio sky.
4. Cosmic rays - what is the origin of the most energetic particles in the universe?
5. Solar and space environment - mapping the structure of the solar wind, how it relates to solar bursts, and how it interacts with the Earth.
6. Cosmic Magnetism - what is the origin of the large-scale magnetic fields that pervade the universe?

Tuesday, May 17, 2011

Monday, May 16, 2011

Chilbolton & Wherwell Local Information Day

On Saturday 14 May 2011 a visitors' day was held at the LOFAR Chilbolton site. This was a requirement of our LOFAR planning application, namely that we host some form of public-information event for the local communities of Wherwell and Chilbolton Village. Three members of the LOFAR-UK team (Derek McKay-Bukowski, Brian Ellison and Malcolm Coe) were at hand to show visitors around the Low-Band and High-Band Arrays and to give them a rare glimpse inside the RF-container.

In all, it was a very successful day, with lots of interesting questions. In total we had over 75 guests at the site. We certainly hoped that all our visitors enjoyed the event. Hopefully, we will be able to hold an open day for the general public sometime in the future as well. And many thanks to Brian and Malcolm for giving up part of their weekend to assist Derek with explaining the LOFAR-UK facility.

Brian Ellison (in the high-vis vest) explains how the LBA aerials work to locals including Graham and Brian Patterson (on his left and right respectively).

Tuesday, May 3, 2011

LOFAR on the Naked Scientist Podcast

I discuss LOFAR and LOFAR-UK with Andrew Pontzen on the special National Astronomy Meeting edition of the Astronomy podcast for the Naked Scientists.

MP3 of just the LOFAR segment.

Link to the whole podcast (including a transcript).

LOFAR on Google Maps

Another fun post from our friends at KAIRA - LOFAR stations now visible on Google Maps.

Not Chilbolton yet though - still just empty fields shown at the moment for our UK station.

How Does LOFAR Work (Parts 10 and 11) from the KAIRA blog

We're getting a bit behind in the series, but here are the next two installments from the KAIRA blog about how LOFAR works:

Part 10 : Multi-beam operations (explaining one of the techniques used in the press release about the first peer reviewed science results from LOFAR).

Part 11 : Ambiguities (about phase errors)

Wednesday, April 20, 2011

LOFAR-UK at the UK National Astronomy Meeting

Anyone who follows LOFAR (or me) on Twitter probably knows that LOFAR has been well represented at the UK National Astronomy Meeting (NAM) taking place in Llandudno, Wales this week. LOFAR-UK decided to run an exhibit stand to try to educate the UK astronomical community about LOFAR in general and the UK involvement in LOFAR specifically.

Below is the picture of the stand we put up, with 3 large LOFAR-UK banner posters and LOFAR-UK bookmarks (made by SEPnet, who also provided some pencils, postcards and post-it notes to give out), a computer playng a DVD of some of the different LOFAR-UK videos we have on YouTube, brochures describing LOFAR in general (kindly provided by ASTRON), a leaflet about the Chilbolton observatory (provided by STFC), LOFAR-UK pens and post-it notes designed by yours truly, plus printouts of two of the recent press releases (First Light Including Chilbolton Station, and the First Peer Reviewed Science Result from LOFAR) and some other pictures.

Here's a picture of all the give-aways. The pens were a definite hit (described as the best freebie at NAM), and we have just a handful left to giveaway tomorrow (the last day of the meeting).

We also took along a demo low band antenna (LBA) which I'm holding in the below picture. We have used this to illustrate the technique behind putting up the antenna several times at coffee and lunch breaks, and also to the team from the Astronomy Now YouTube Channel

 There has been some definite interest, and I have given interviews about LOFAR (and LOFAR-UK) for the Jodcast, The Naked Scientist, the Sky at Night vodcast and Astronomy Now YouTube channel. So stay tuned for those.

 Other LOFAR related events at NAM included a talk by Christian Vocks on observing the Sun with LOFAR (with some interesting information on the Potsdam LOFAR station), plus a plenary lecture on EISCAT-3D (a project using some similar technology to LOFAR).

All in all I think it's gone very well, and I want to say thanks to all the members of the LOFAR-UK community who have helped me to "man the stand" this week. They have included Emma Rigby, Melanie Gendre, Lyndsay Fletcher, Rob Beswick, Somak Raychaudhury, Paul O'Brien and Paul Alexander.

Thursday, April 14, 2011

First peer reviewed science from LOFAR

The below press release appears today at ASTRON and Jodrell Bank Observatory in Manchester, describing the first peer reviewed scientific results from the LOFAR telescope, from a team led by LOFAR-UK member Dr. Ben Stappers of the University of Manchester. 

LOFAR takes the pulse of the radio sky

The powerful new International LOFAR telescope, designed and built by ASTRON, is allowing an international team of scientists to have their “best-ever look” at pulsars: rapidly rotating neutron stars, created when massive stars die. In the first refereed scientific results from the new European telescope LOFAR (Low Frequency Array) soon to appear in Astronomy & Astrophysics, the scientists present the most sensitive low-frequency observations of pulsars ever made.

Because of its unique design, LOFAR can observe in many different directions simultaneously. For this image, five pulsars, spread over the entire sky, were observed simultaneously.  

LOFAR is the first in a new generation of massive radio telescopes designed to study the sky at the lowest radio frequencies accessible from the surface of the Earth with unprecedented resolution. Deep observations of pulsars are one of its key science goals.

Lead author on the paper Dr. Ben Stappers, from University of Manchester (UK), said: "We are returning to the frequencies where pulsars were first discovered, but now with a telescope of a sophistication that could not have been imagined back in the 1960s.”

The chance detection of the first pulsar in 1967 is considered one of the great discoveries in astronomy. Astronomers got their first glimpse of pulsars by using a radio telescope sensitive to frequencies of 81MHz (roughly the same frequency as a commercial FM radio station). 

With LOFAR, astronomers have gone back to some of the same techniques used in the first pulsar observations, but have used modern computing and optical fibre connections to increase many times over the power of their telescope. This will allow LOFAR to analyse regular pulses of radio emission and probe such things as the physics of gravity and the properties of the material that pervades our Galaxy.

Dr. Stappers: “Even though these are just the first test results they are already showing spectacular promise.”

LOFAR works by connecting thousands of small antennas spread right across Europe using high speed internet and a massive supercomputer near its central core at ASTRON in the Netherlands.

The LOFAR telescope has no moving parts, instead relying on adding digital time delays to "point" the telescope in a particular direction. This approach offers a much-greater level of flexibility in the way astronomers can analyse the data. For instance, unlike a conventional radio telescope, it is possible to point in multiple directions simultaneously simply by having the computer crunch more data. For astronomers who want to search for new pulsars, this means they can scan the sky much more quickly. 
 Dr. Jason Hessels from ASTRON said: “A traditional radio telescope is limited to viewing a very small fraction of the sky at any one time. LOFAR casts a much broader net, which is going to help us discover new pulsars and detect explosions that were too rare to catch with past in a new approach to understanding these exotic objects.”

The team's next step is to harness LOFAR's capabilities to address some of the long-standing mysteries about how pulsars shine and also to discover nearby pulsars that were missed by past telescopes. "LOFAR has the potential to find all the undiscovered pulsars in the neighbourhood of the Sun and to reveal rare explosions in our Galaxy and beyond. We're very excited to see what's out there." says Dr. Joeri van Leeuwen from ASTRON.

LOFAR is capable of detecting radio waves over a very large range of frequencies, all the way from 10MHz to 240MHz. As well as searching for pulsars, LOFAR will be used for making deep images, cosmology, to monitor the Sun’s activity and study planets. LOFAR will also contribute preparations for the planned global next generation radio telescope, the Square Kilometre Array (SKA).

The full article with the new results can be found here:

More information about ASTRON:

More information about LOFAR:
The International LOFAR telescope is a European collaboration, led by ASTRON Netherlands Institute for Radio Astronomy. By combining thousands of simple antennas with a powerful supercomputer, LOFAR can observe large parts of the sky very fast in different directions simultaneously on relatively unknown low frequencies. This opens up a new window to the universe for astronomers. See also:

Wednesday, April 13, 2011

Aerial photographs of LOFAR-UK Chilbolton

Some dramatic photographs have just been posted on the Press and Media Image Library of the UK's Science and Technology Facilities Council (STFC). These show the LOFAR station at Chilbolton, Hampshire, UK, as seen from the air. Although there are plenty of photographs of various LOFAR stations from the ground, and plenty of diagrams showing the layout of the sites, this is a good opportunity to get a bird's-eye view of what a station looks like.

The credit for all these images goes to Guy Gratton, who took the photographs during the afternoon of Friday 8th April 2011, and who graciously gave permission for their use by the STFC/LOFAR community. The images were taken from an aeroplane flying at an altitude of approximately 300 metres (1000 ft) over the site, through an open door on the aircraft to avoid any window reflections.

Banking away from the LOFAR field, you can see the Chilbolton 25m dish
Guy Gratton (c) 2011, hosted by STFC.)

Looking specifically at the LOFAR-UK station (LOFAR-ID = UK608). The HBA is on the left and the LBA is on the right. If you look carefully, you can just make out the RF-container in the space between where the two fields meet and the access road. (Photo: Guy Gratton (c) 2011, hosted by STFC.)

When you start to move further back, more the surrounding facilities become apparent. Apart from the main 25m dish, there is a small 4.5m dish on the right-hand side, just below the LOFAR compound. (Don't forget you can click on images for a slightly enlarged view.)

Looking at the site from even further away, the scale of the Chilbolton Observatory becomes clear. (Photo: Guy Gratton (c) 2011, hosted by STFC.)

The LOFAR-UK site, as seen from the air. 
(Photo: Guy Gratton (c) 2011, hosted by STFC.)
The above photograph is a great way to appreciate the scale of an international LOFAR station. The dish near the top of the photograph is the 25m parabola of the Chilbolton Observatory.

Check the STFC's Press and Media Image Library for all high-quality photographs of the LOFAR-UK station. You can also find full-resolution versions of some of the above photographs, suitable for use in printed media. Thanks goes to the Chilbolton Observatory and UK608 project teams, the RAL-Space outreach team and, of course, Guy Gratton for the great photographs.

Friday, April 8, 2011

Thursday, March 31, 2011

What might LOFAR see of the first stars?

One of the main science drivers for LOFAR is the detection of the point in the history of the Universe when the first stars turned on.

We know that the Universe formed in a Big Bang, after which it was filled a hot soup (plasma) of elementary particles (like electrons, protons, neutrons and photons as well as much more exotic things). When the Universe cooled sufficiently, the electrons combined with the protons to make hydrogen atoms. At that point the photons which had previously been stuck bumping around between the particles could finally stream across the universe - and we see from that time the first light in the Universe - now cooled to microwave radiation (what we call the cosmic microwave background, or CMB).

After the CMB not much happened for a long time. There still wasn't a lot of structure in the Universe - no stars or galaxies. There was nothing to create any light - so we call this period the "dark ages". During this time the material in the Universe ever so slowly collects together under its gravity. Eventually parts of the Universe start getting more and more dense, and the first stars turn on in the densest parts. Suddenly there is light in the Universe once more, and all these new photons hit the hydrogen atoms and strip them of their electrons (ionizing them, but since they started before the CMB as separate protons and electrons, we like to call it "reionization").

As I described in a previous blog post "LOFAR in Sky and Telescope", and you can read about in the May 2011 issue of Sky and Telescope, neutral hydrogen emits a characteristic spectral line at 21cm (1.4 GHz), due to hyperfine splitting of it's ground state. The neutral hydrogen that was around in the Universe just before the first stars turned on was emitting this line, which is now redshifted to much lower frequencies (which we think should be in the range that LOFAR can detect). Suddenly at the redshift which the first stars turned on, the amount of this 21cm emission will drop dramatically. It is this phase change in the Universe which LOFAR hopes to detect.

A slice through a simulation of the reionization of the Universe. Credit Illian Illiev, SEPnet/Sussex
Exactly when and how the first stars turn on in the Universe is an important measurement to further our understanding of cosmology. Researchers involved in LOFAR (and LOFAR-UK) are working on models of what LOFAR and other telescopes like it might see. One such researcher is SEPnet Fellow Dr. Illian Illiev at the University of Sussex. It was his images and animations of what reionization might look like which were used to illustrate the Sky and Telescope article.

Reionization Animation.

Here's a description of the image and animation provided by Illian:

This is what a giant radio telescope like LOFAR is expected to see as it looks deeper into the past (going right) - a sea of neutral hydrogen atoms (yellow) gently excited into emission by the cosmic microwave background photons.

As the very first stars and galaxies form in the universe, some of their radiation is energetic enough to kick out the electron out of the hydrogen atom (a process called ionization), which leads to the gas 'disappearing' from point of view of the radion telescope, illustrated by the blue regions above, growing with time (going left) as more stars form over time.

The variation in the intensity of the yellow across the image indicates regions with different density, the higher the density, the more intensive the colour (since there is higher concentration of emitting atoms there). This is a manifestation of the 'Cosmic Web' of structures - a honeycomb-like structure which forms due to gravity.