Wednesday 30 April 2014

Snow again

Yesterday it started snowing again at Sodankylä... no summer just yet!

Snow at the EISCAT dish at Sodankylä on 29-Apr-2014. (Photo: D. McKay-Bukowski)

Tuesday 29 April 2014

McCanister Cluster

As everyone knows, we need some serious computational power for data analysis. Therefore, as part of our computational method development, we purchased new Mac Pros. These machines have canister-shaped designs, hence the name!

Our cunning plan is to daisy chain Mac Pros, allowing proper computational power with high data rate between the machines.

We have named the canisters according to certain historical figures, or more precisely according to a Finnish band

Freud, Marx, Engels and Jung - Our new McCanister Cluster!

Monday 28 April 2014

Comparing solar data

Last week, we reported on a spectacular solar event that we caught with KAIRA. As it turned out, the LOFAR station in England (UK608 Chilbolton) also caught the event, although only part of it.

Today, we have the data for the event as seen from both stations. Although we have a lot more KAIRA data, we have clipped it to make it match the same time range as the UK608 data.

Although very similar, there are some differences between the two stations. KAIRA's layout (REF) is different to that of the layout of UK608 (REF) and the UK station has twice the number of aerials. At the time of the measurement some of the KAIRA aerials were still out of action, due to the storm damage.

The stations are also at a different latitudes/longitudes. Therefore the relative topocentric position of the sun with respect to the two arrays is different. Certainly at KAIRA, the sun is lower in the sky. This also affects the relative position with respect to the polarisation orientation of the aerials (although the sun is largely unpolarised, the aerials do have a different response as we are only using one dipole for these measurements).

Finally, the radio-frequency interference (RFI) environments are slightly different between the two stations.

Friday 25 April 2014


Quintessentiallly English (QE) is the only way to describe the village of Chilbolton. This is such a quaint place, with so many fond memories of a couple of years of very hard, but very rewarding work.

Some random house in the village of Chilbolton (Photo: D. McKay-Bukowski)
This is the last of our photographs from England. On the weekend, your humble reporter is heading back home to Finland. But for now...

Have a absolutely spiffing weekend, what!

Thursday 24 April 2014

The Blue Land Rover

Come on... we can't visit Chilbolton without a gratuitous photograph of "my" old Blue Land Rover, can we?

The real reason I visited Chilbolton... (Photo: D. McKay-Bukowski)

Wednesday 23 April 2014

Sunset at Chilbolton

Today, we are still posting from the United Kingdom.

At this time of year, when the weather is clear (and there is always fine weather at Chilbolton... just ask the LOFAR teams!), one can get the most amazing sunsets.

The Chilbolton 25m dish in the evening light (Photo: D. McKay-Bukowski)

Sunset at Chilbolton Observatory (Photo: D. McKay-Bukowski)

Tuesday 22 April 2014


Another post from our visit to the United Kingdom. Today we have some photographs from the LOFAR station at Chilbolton Observatory.

The UK608 high-band array... no snow, no frames. In the
background is the 25m dish. (Photo: D. McKay-Bukowski)

The UK608 low-band array. (Photo: D. McKay-Bukowski)

Monday 21 April 2014

Spectacular solar radio event

Last Friday, KAIRA observed the most amazing radio event from the sun. There was a strong X-ray event, which corresponded to an amazing multi-frequency solar event in the radio. The following plot is from the GOES X-ray monitor (source: NOAA/SWPC)

The event was detected at KAIRA and the following plot shows the entire event sequence.

KAIRA detecting of the solar radio event (Image: D. McKay-Bukowski)

The initial event was preceded by a smaller, fainter event. However the first of the strong radio bursts was very strong and mostly uniform in frequency distribution.

Zooming in on the initial event (Image: D. McKay-Bukowski)

 The subsequent events were much more complicated. In particular, there was a very slowly decaying radio event, which cascaded down through the different frequencies of the Low-Band Array (which was operating at the time).

The main event... very complex! (Image: D. McKay-Bukowski)

What is really curious is the ripple effect through the different frequencies. Is this an interferometric effect from the coupling between antennas? However, these data were taken with a single LBA aerial.

It will be interesting to see what auroral activity occurs over the next few days. Although it is getting close to the midnight-sun season, KAIRA will be able to monitor the events using the new riometry modes.

Overall it was a very interesting event. We will be conducting a number of dedicated solar observing events over the summer with KAIRA, so hope to report on more solar data in the next few months.

Sunday 20 April 2014

Test Valley

Another post from our visit to Chilbolton Observatory, England.

There seems to be a part of England where everything is "under test". Nothing is certain and all manner of things seem to be being checked. Welcome to the Test Valley (yep, we're checking this valley... just in case).

The cause of this curiosity is that the river is actually called the Test River. That is, "Test" is the name of the river. (Only in England!)

Warning! This is a River Test... please be careful! (Photo: D. McKay-Bukowski)

So, not only is there a "Test River", but there is also a "Test Shop", "Test Bridge", "Test Cottage"... in fact, as mentioned, the entire valley is being tested.

You certainly can't beat that for quality control!

Saturday 19 April 2014

Strange radio sky

A rather odd all-sky image appeared in the last hour. As you can see, the dominant flux seems to be coming from the Galactic plane, but away from the Galactic centre.

I am guessing that strong scintillation caused Cas A and Cyg A to particularly fade at that point and the autoscaling has thus highlighted the rest of the Galactic plane. In any case, Cyg A is pretty low to the horizon at this point.

Or perhaps there is a riometric event causing a sweep of absorption in the northwest (top-right, due to the sky-view orientation). After all, there has been some strong Solar activity in the last couple of days.

Still, it is an interesting all-sky image. It might make for a neat little project to investigate the data around this particular time.

Friday 18 April 2014

Return to UK608

Today, I have been working at the LOFAR station at Chilbolton (UK608). We've been conducting system tests and have been investigating a radio-frequency interference (RFI) problem.

Chilbolton Observatory (Photo: D. McKay-Bukowski)

It is always nice to visit the observatory here. (And check that my old Land-Rover is doing okay.) So, today's photograph is from the observatory here in England.

Have a nice weekend.


Wednesday 16 April 2014

KAIRA -- lyhytdokumentti

Last week we published a film on KAIRA. Today, we have the film again, but with Finnish text/subtitles.

KAIRA on Kilpisjärvelle rakennettu ilmakehän, lähiavaruuden ja syvän avaruuden tutkimukseen tarkoitettu radioteleskooppi. Sen on rakentanut ja sitä operoi Oulun yliopiston Sodankylän geofysiikan observatorion. KAIRA-lyhenne tulee englanninkielisisestä projektinimestä Kilpisjärvi Atmospheric Imaging Receiver Array.

KAIRA-vastaanottimessa on kaksi antennikenttää, joista matalampitaajuinen niin sanottu LBA-kenttä mittaa taajuusalueella 10-90 MHz ja korkeampitaajuinen HBA-kenttä alueella 110-270 MHz. KAIRA voi toimia osana eurooppalaista sirontatutkajärjestelmää EISCATia. Norjan Tromssassa sijaitsee 224 MHz:n VHF-lähetin, jonka ionosfääristä sironnutta signaalia voidaan vastaanottaa Kilpisjärvellä. Lähitulevaisuudessa tulemme rakentamaan osana kansainvälistä yhteistyötä uuden hajautetun sirontatutkajärjestelmän Kalotin alueelle. Tämä projekti kulkee nimellä EISCAT_3D. Siinä tarvittavaa tekniikkaa kehitetään KAIRA-asemalla!

KAIRAn antennikentät on alunperin suunniteltu LOFAR-nimiseen radioastromiaprojektiin. Voimmekin käyttää radioastronomiaan suunniteltuja antenneja ja signaalinkäsittelyä hyvin suoraan ilmakehän ja lähiavaruuden tutkimukseen. Luonnollisesti teemme yhteistyötä useiden LOFAR-asemien kanssa eri radioastronomiaprojektien kanssa.

Tämä lyhytdokumentti kertoo KAIRAn rakentamisesta, asemalla tehtävästä tutkimuksesta ja EISCAT_3D-projektin pitkän tähtäimen näkymistä. KAIRA-aseman rakentamisen on rahoittanut Oulun yliopisto, Euroopan aluekehitysrahasto Lapin liiton kautta ja Sodankylän kunta.

Tuesday 15 April 2014


I was in London the other week when I saw a car with a cool number plate... "FIN 1". The fact that it was parked outside the Finnish Embassy might not be a pure coincidence...

I wonder who gets "FIN 2"?

Monday 14 April 2014

Video of ionospheric scintillation

Recently, we ran a small article on ionospheric scintillation and how dramatically it can change depending on atmospheric conditions. A few days later we showed two more interesting plots, both to the same scale, which demonstrated how substantial the different ionospheric scintillation conditions can be.

However, there is nothing quite like a video to really show how the scintillation can affect the signal. So today, we have just that!

What we did was make all-sky images for each of the two extremes shown in that last post we made on the topic.

The observing frequency was the same in both cases 58.594 MHz), 1 second integration per frame, 195.3 kHz bandwidth. The sequence is sped up somewhat (5 minutes data in about 30 seconds of video). As the time of day was the same in both instances, so the radio sky is in roughly the same orientation.

On the 25.12.2013 (left), the ionosphere exhibited extreme scintillation. The two bright sources (Cas A and Cyg A) are flickering quite dramatically. However, exactly two days later (27.12.2013, right), the ionosphere was relatively stable and the brightnesses of the two strong radio sources remain steady.

Sunday 13 April 2014

Impacts of space weather

Space weather is an important issue and many nations are now realising the implications of forecasting, assessing risk and monitoring for space weather events.

The Royal Academy of Engineering (RAEng) in the United Kingdom last year published a good overview of the British view entitled "Space weather: impacts on engineered systems, infrastructure and society".

The University of Birmingham (UK) works closely with the RAEng and has announced a fully Funded PhD place available in the Space Environment and Radio Frequency (RF) Engineering Group. The UK placement project is as follows:

Comprehensive, global and timely specifications of the earth's ionosphere are required to ensure the effective operation, planning and management of many radio frequency systems. Many techniques have been developed to measure ionospheric refractivity; these include ground and space - based ionosondes and the use of Global Positioning System (GPS) measurements made with both ground and space - based receivers.
Ionospheric data assimilation systems are currently under development that will combine disparate ionospheric measurements with an ionospheric model. The problem is mathematically under - determined since the amount of information that can be extracted from most ionospheric measurements is low compared to the required resolution of the electron density field under investigation. Therefore it is necessary to utilise a priori information about the state of the ionosphere in order to solve the inverse problem. Many inverse techniques have been proposed; however, this project will investigate the application of the local ensemble transform Kalman filter (LETKF) to physical models of the ionosphere/thermosphere system. The LETKF is a method whereby the data assimila tion is performed in local “regions” around each model grid point. Each region is processed independently, naturally leading to parallelisation, and the grids are later assembled into the global analysis. The LETKF has been well - tested and shown to be both computationally efficient and flexible. However, it has not yet been applied to the ionosphere. The intention of this project is to achieve a significant improvement in current ionospheric forecasting.

The project will be conducted within the Space Environment and RF Engineering group at the University of Birmingham. However, it is anticipated that the work will involve collaboration with researchers in Europe and the USA.

One fully - funded studentship (tax - free stipend of £13863* per annum) is available for Home/EU students to begin this inter - disciplinary 3 - year programme in October 2014.
*subject to inflationary variation Applications are open to students that have, or expect to obtain, a 1st class degree (or equivalent EU/overseas degree) in a wide variety of scientific disciplines including mathematics, physics and natural sciences. Due to the nature of the project, the applicant must be able to demonstrate a high level of mathematical ability.
If you are interested in this UK-based PhD position at the University of Birmingham, then informal enquiries should be made to .

Friday 11 April 2014

Perfect April Afternoon

During last weeks, we have been enjoying perfect winter weather and sunny days in Sodankylä! Today we have a photo of the main building of the observatory and EISCAT antenna taken on the Kitinen river during one of sunny April afternoons.

Thursday 10 April 2014

2014 LOFAR Science Workshop conference dinner

The conference dinner for the 2014 LOFAR Science Workshop was held in the Pakhuis de Zwijger on the waterfront in Amsterdam. With so many fantastic talks during the day, the entire evening was abuzz with amazing discussions and ideas. And, to keep everything focused further, the organisers had asked for speakers to provide high-resolution images of their projects and results. These were projected onto nine massive screens that surrounded the eating area.

Wednesday 9 April 2014

KAIRA film

At the LOFAR Science Workshop 2014 in Amsterdam, we premièred the KAIRA film. This was produced by SiteEye in conjunction with Sodankylä Geophysical Observatory, U. Oulu, ASTRON, EISCAT, and many others. (Versions with subtitles in many languages will be posted later.)


The film is also available with Finnish subtitles (LINK). 

Tuesday 8 April 2014

LOFAR station Norderstedt

Guten Tag! This is Germany calling!

At the Hannover Messe (the world's largest industrial fair), ASTRON, the University of Hamburg and Bielefeld University will sign tomorrow a contract for construction of a new German LOFAR station for the International LOFAR Telescope (ILT).

The new station will be located at Norderstedt, close to the city of Hamburg.

Click map to enlarge (image based on an original by ASTRON)

The additional of another station to the ILT network is important not just for the resources it provides to local education, research and industry, but because of its important contribution to the ILT itself. Each LOFAR station adds valuable collecting area, thus allowing astronomers to detect ever-fainter signals. However, the placement of the new station is such that it provides critical intermediate baselines, thus improving the imaging capabilities of the ILT.

But there is also the knowledge factor as well. Each new station gives an opportunity for new researchers and new expertise to join the strong ILT community. This is vital for the local knowledge base and the advancement of science for participating regions and countries.

In the case of the new German station, researchers at the University of Hamburg, led by Prof. M. Brüggen, specialise in studying the formation and evolution of clusters of galaxies from the early Universe to the present era. The group at Bielefeld University, led by Prof. D. Schwarz, studies the distribution of galaxies on the largest observable distances in the Universe, which carry imprints from the era of cosmological inflation.

Signing of the contract will take place tomorrow at the Holland High Tech Pavilion at the Hannover Messe, in Hall 2 booth D10 from 12:00 - 12:30 hours (CEST).


Monday 7 April 2014

LOFAR Science 2014

This week, is the LOFAR 2014 International Meeting, being held in Amsterdam.It features the LOFAR Users Meeting, the LOFAR Community Science Workshop and a workshop about LOFAR’s first all-sky survey, the Multifrequency Snapshot Sky Survey (MSSS).

KAIRA will feature in the LOFAR Community Science Workshop. This part of the conference is the third annual meeting of the LOFAR science collaboration since the onset of regular LOFAR science operations. These workshops aim to bring together members of the wider collaboration including active members of the Key Science Project teams as well as various EU and international members of the LOFAR user community. This part of the conference will last two full days and  will feature a wide range of talks on technical developments, software enhancements, improvements in calibration and imaging techniques, and of course exciting new scientific results. The workshop program will cover the gamut of the LOFAR science case from cosmology and extragalactic research to Galactic, planetary, and solar system topics.


Friday 4 April 2014

The KAIRA snowscape

It's Friday again and, after a dearth of Friday photographs, we've an absolute treat for you today.

Back in November of 2013, we ran an extended campaign at KAIRA with the University of Southampton, observing pulsars, incoherent scatter radar and various riometry experiments. On one morning, we actually had some clear weather, giving us a chance to take some photographs. And today we feature one of these.

KAIRA 2013-11-03 (Photo: D. McKay-Bukowski)

The photograph was taken on 3rd November 2013, and shows the Low-Band Antenna (LBA) array in the central foreground with the HBA behind it and a bit to the right. It is also possible to see the site containers too. The mountains in the background are (from left to right) Pikku Malla, Iso Malla and Sallorássa. The first two are in Finland and the latter is in Norway.

You can click on the above image to see a somewhat larger version. However, for those who really want high-resolution, we have a 3200x1000-pixel version (4 MB) at the KAIRA press-and-media page. Or, if that is not enough, we also have a huge 9600x3000-pixel version (30 MB... Warning: this image may take a while to download). Oh, and a big thank-you to Poppy Martin (U. Soton) for lending her amazing camera to me in order to make the image.

Have a nice weekend, everyone!

Thursday 3 April 2014

LOFAR Planetarium

As we know from the various images from KAIRA (including the latest all-sky image on the right), the LOFAR system is suitable for creating maps of the entire visible sky.  With a day of observing, it is possible to therefore image the entire radio-sky as seen from that location.

Showing the entire sky is not easy; there are always issues with the projection to use and conveying a sense of angular scale. For visual observing the traditional way of doing this is via a planetarium.

In 2010, at the time I was working on the LOFAR-UK project, I had a conversation with Jenny Shipway from the Winchester Science Centre regarding the new LOFAR facility at Chilbolton. We realised that a planetarium would be ideal for portraying the data that the telescope could generate. A quick mock-up version was created using some 408 MHz data, which demonstrated that the concept was feasible.

Since then, the LOFAR-Planetarium idea was formalised and some more people got involved -- in particular, Andrew Fletcher, who now runs the project. We took a huge series of data from the LOFAR station at Chilbolton and generated high-resolution (3600x1800 pixel) images that can be projected directly from a digital planetarium, such as the one at Winchester.

The equirectangular projection of the radio sky (Image:

Modern planetaria are capable of overlaying optical and radio data and fading seamlessly between them. Thus it is possible to use these images to demonstrate the relationship between the optical and radio sky and use this as a starting point to explain the astrophysics behind it.

The LOFAR Planetarium is a public outreach project of the LOFAR-UK consortium, funded by the Science and Technology Facilities Research Council (STFC) and Newcastle University.


Wednesday 2 April 2014

Ionospheric scintillation revisited

On Monday we showed a plot of the ionospheric scintillation of Cas A. Today we have some more data, prompted by a recent data request from a researcher at MAARSY. The two plots cover the same time period, the same scale, the same source and approx. the same local sidereal time. The difference is that one was two days after the other and the contrast in ionospheric scintillation conditions is dramatic.

We also have another project with ionospheric scintillation and it is an area of active research with the instrument.

Oh, and as a bonus, we also captured interferometric data during both of the above times. We'll post a video of the image sequences soon. So, stay tuned!

Tuesday 1 April 2014

Moving out

I've actually been gone for well over a year now, but my old office at RAL still had a few things in it. There had been no need to completely empty it, as there was sufficient desk space for temporary visitors and students to use it.

However, now there is a need for extra space at RAL, so that meant the final clear-out before the room was reallocated. During a recent visit to 'the Lab', that final pack was completed and I took one last photograph of the door that marked 'home' for a few years.

The old office door... vale!
The inset panel on the door was a cutout from a planning map for the placement of the LOFAR UK608 Low-Band array.