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Here is a presentation by Pim Schellaert (referenced in the article) with some more information:
http://www.lofar.org/wiki/lib/...

I've seen a presentation of their more recent results, but that doesn't seem to be public yet, I can't find a link.

One of the coolest things we did recently with the LOFAR telescope was to observe the Solar Eclipse in real time, I think it has never been done with a radio telescope before: https://www.youtube.com/watch?...

In general you can find a lot of info about what we're doing with the LOFAR telescope here:
http://www.astron.nl/dailyimag...
and here: http://www.lofar.org/wiki/doku...

Here is a presentation by Pim Schellaert (referenced in the article) with some more information:
http://www.lofar.org/wiki/lib/...

I've seen a presentation of their more recent results, but that doesn't seem to be public yet, I can't find a link.

One of the coolest things we did recently with the LOFAR telescope was to observe the Solar Eclipse in real time, I think it has never been done with a radio telescope before: https://www.youtube.com/watch?...

In general you can find a lot of info about what we're doing with the LOFAR telescope here:
http://www.astron.nl/dailyimag...
and here: http://www.lofar.org/wiki/doku...

Yes, but you have to realise that the British never like to give any credit to the Dutch for anything...

  - The world's largest radiotelescope is based in the Netherlands.
  - The world's highest rate of cycling is in the Netherlands.
  - The Dutch crime rate is so low that they're having to import prisoners from other countries to avoid making prison officers redundant.
  - The Dutch manage to be the world's second largest agricultural exporter despite having just 0.03% of the world's land.
  - Dutch roads are the safest in the world.
  - Dutch obesity rates are amongst the world's lowest.
  - Teenage pregnancy rate is amongst the world's lowest.
  - Drug abuse rates are amongst the world's lowest...
  - Dutch children are the happiest in the world.

However, Britain prefers to defer to the US for advice on all these things...

If the summary had pointed us to the correct website the few who read the article itself would have seen the lofar isn't simply in the UK. The LOFAR is to big for that. There is one substation in the UK, most are in the Netherlands (since the center is there), some are in Germany, one in France and one in Sweden. These substations are assembled in a giant phased array by means of a supercomputer. This array can look at multiple parts of the sky at the same time while having a great resolution in low frequencies.

If the summary had pointed us to the correct website the few who read the article itself would have seen the lofar isn't simply in the UK. The LOFAR is to big for that. There is one substation in the UK, most are in the Netherlands (since the center is there), some are in Germany, one in France and one in Sweden. These substations are assembled in a giant phased array by means of a supercomputer. This array can look at multiple parts of the sky at the same time while having a great resolution in low frequencies.

... instead of a PR puff piece, see the LOFAR web site.

For your information, the LOFAR system also processes data immediately. All the stations are connected with 10Gbit networks to the central processing system in Groningen.

Each LOFAR antenna produces 0.8 Gbyte of data per second. When finallized, the system will consist of about 7000 antenna spread out over about 40 field most of which are in the Netherlands, but about ten of them will be abroad. I understand that each field will perform some preprocessing before the data is send to the central processing unit where it is correlated and further reduced before it being stored and made available for off-line processing. See here for a detailed description.

I do not understand what is so interesting about this. Another dish added to various international VLBI networks. There is also one such dish near Urumqi in China in a very remote area. There are so many of these kind of dishes around the world. Even here in the Netherlands we have one. But we also have LOFAR, which is also capable of producing large amounts of data everyday. This kind of systems usually only operate for short periodes and the data produced are immediately processed and only the results are stored.

Took me a while to find, but this is the location.
And also the corresponding google maps location (point 23 on the other map). Too bad the satellite image doesn't show anything yet.

Read the scientific goals of LOFAR here: http://www.lofar.org/astronomy/key-science/lofar-key-science-projects

And here: http://www.lofar.org/geophysics/scientific-rationale/scientific-rationale

And even here: http://www.lofar.org/agriculture/fighting-phytophtora-using-micro-climate/fighting-phytophtora-using-micro-climate

But "extraterrestrial intelligence" is surely teh attentionz grabb0r!!!1

Read the scientific goals of LOFAR here: http://www.lofar.org/astronomy/key-science/lofar-key-science-projects

And here: http://www.lofar.org/geophysics/scientific-rationale/scientific-rationale

And even here: http://www.lofar.org/agriculture/fighting-phytophtora-using-micro-climate/fighting-phytophtora-using-micro-climate

But "extraterrestrial intelligence" is surely teh attentionz grabb0r!!!1

Read the scientific goals of LOFAR here: http://www.lofar.org/astronomy/key-science/lofar-key-science-projects

And here: http://www.lofar.org/geophysics/scientific-rationale/scientific-rationale

And even here: http://www.lofar.org/agriculture/fighting-phytophtora-using-micro-climate/fighting-phytophtora-using-micro-climate

But "extraterrestrial intelligence" is surely teh attentionz grabb0r!!!1

http://www.lofar.org/

But it might depend a bit on how one bends definitions (min/max distance between receivers etc.)..

"The antennas are simple enough but there are a lot of them - 25000 in the full LOFAR design. To make radio pictures of the sky with adequate sharpness, these antennas are to be arranged in clusters that are spread out over an area of ultimately 350 km in diameter. (In phase 1 that is currently funded 15000 antenna's and maximum baselines of 100 km will be built). Data transport requirements are in the range of many Tera-bits/sec and the processing power needed is tens of Tera-FLOPS."
http://www.lofar.org/p/geninfo.htm

http://www.lofar.org/

But it might depend a bit on how one bends definitions (min/max distance between receivers etc.)..

"The antennas are simple enough but there are a lot of them - 25000 in the full LOFAR design. To make radio pictures of the sky with adequate sharpness, these antennas are to be arranged in clusters that are spread out over an area of ultimately 350 km in diameter. (In phase 1 that is currently funded 15000 antenna's and maximum baselines of 100 km will be built). Data transport requirements are in the range of many Tera-bits/sec and the processing power needed is tens of Tera-FLOPS."
http://www.lofar.org/p/geninfo.htm

How about:

http://www.lofar.org/
http://www.astron.nl/p/lofarframe.htm

There is a suspected but yet unproven relation between cosmic rays and lightning. The theory is that when a cosmic particle strikes the atmophere, it ionises a path though the atmophere. This then provides a conduit for lightning.
This is currently a hot research topic in particle physics and meteorology.

A professor in Nijmegen and a collegue of mine are studying this phenomena (Heino Falcke and Lars Bähren)
http://www.physorg.com/news4162.html
http://www.lofar.org/workshop/23Apr07_Monday02/LOF ARWorkshop_Apr07_HeinoFalcke.pdf

So many people depend on 'the Internet', and assume it will 'just work'. But it's rapidly coming to the point where you can't use it, without someone getting upset about what you're doing and sending the police round to lock you up.
And of course it doesn't 'just work'. It's a 'best-effort' network for carrying sequences of 0's and 1's around, which neither knows nor cares what the 0's and 1's mean.
Just because *you* think it's a virus, doesn't mean *I* think so. It might be 500 DVDs per second of 'star noise' from the radiotelescope, just doing its job in the normal way.

I just thought to add a link: http://www.lofar.org/p/systems.htm
Those numbers aren't exactly the same as the ones I quoted, it might be the website is out of date with the latest info, or my memory is failing me. They're still the same order of magnitude though. It migh just depend if you quote raw data rate, correlated data rate, or the rate at which the scientific results come out.

The bandwidth of the connection between each Remote Stations and the Central Processing Systems will be ~10 Gbit/s, of which ~ 2.5 Gbit/s will be occupied by the sustained datarate resulting from the sensors.

LOFAR produces very large data streams, especially for the astronomy application (e.g. 6 TB of raw visibility data for an 8 beam, 4 hour synthesis observation, after integration for 1 sec and over 10kHz).

They mention that final post-processing can be done at a central processing station (I am guessing the Blue Gene one) or locally by the users. Only bottlenecks seems to be the bandwidth.

LOFAR post-processing can take place either at the Central Processor or locally with the users (in particular at Science Centers). If the available Internet capacity is sufficient, intermediate dataproducts can be transported to the user, and local processing can be done. Otherwise processing resources at the Central Processor are available for further data reduction (within the limits of the Central Processor processing budget).

At http://www.lofar.org/, he will have to write a ton of software to work the radiotelescope. No-one will do it for him.

But he'll give it away free, libre, gratis. If there's a bug, he wants to know. If someone else wants to make a bigger radiotelescope, he'll want to use it.

Going to court on the back of copyright or patent law to stop someone using it will be the last thing on his mind. Or his employer's.

What they don't talk about is radio-frequency interference.

The main reason they need a supercomputer in the first place is so they can try and remove the effect of the interference - but "taking it all out in software" is exceedingly difficult.

What they don't talk about is radio-frequency interference.

The main reason they need a supercomputer in the first place is so they can try and remove the effect of the interference - but "taking it all out in software" is exceedingly difficult.

Something that hasn't really been mentioned in the article is that this telescope is being constructed now. The land has been bought, the paperwork done and the sensors are being built. Even though it will not be finished until 2008, the 'bits & pieces' can be used before that date. They have been testing the setup on a small array (about 100 antennae) for about 3 years now, and even have some results to show for it.

It's nice for business and science here, but putting it on a field somewhere in East Germany, Tsech Republic etc. might be more economic.

While it is true that building it there might be more economic, consider that this thing is being built where the astronomers are. The 'brain' and control center are located close to the WSRT, the 'other' big dutch radio telescope. Of course, boosting business and science is one of the reasons, but I think it's just practical and fair to use the long tradition in radio astronomy provided by the region..

No, this project is not 'replacing' Hubble, since this telescope will be looking at different wavelengths than Hubble (Hubble = optical, LOFAR = radio). If I understand correctly, LOFAR will mostly be used to research the formation and evolution of the early universe and galaxies, as well as the characteristics of radio sources (esp. black holes). Their site has some more information about the astronomical research..

... the most data-intensive physics instrument on the planet. Today eight major computing centers successfully completed a challenge to sustain a continuous data flow of 600 megabytes per second ...

... the most data-intensive physics instrument on the planet. Today eight major computing centers successfully completed a challenge to sustain a continuous data flow of 600 megabytes per second ...

I believe they will ship the first of these monsters to Livermore to simultate nukes and other deadly stuff. Number 2 will go to the Lofar project. It is basically one huge phased array radio telescope with a diameter of 300 kilometer. Just connect some 10000 simple low frequency (~100 MHz) antennas with big fiber pipes to a central computer and do the beam pointing and imaging all in software.

Who cares how many processors ? It's a minor engineering detail. You don't think the radiotelescope http://www.lofar.org/ with its 6144 chips and 12288 CPUS will be paying any per-processor license fees ?

Machine number one will go to Livermore, probably for doing some nuclear stuf. Number two will go to the Netherlands for the Lofar project. This is a 300 kilometer diameter radio telescope that observes at low frequencies (up to 250 MHz). It constists of thousands of small antennas spread across half the country. Their signals will be interferometrically combined to form the images (compare e.g. to the VLA). Blue Gene will be used to combine all the signals in real time, I believe the total bandwidth from the antennas is some terabyte/sec.

Machine number one will go to Livermore, probably for doing some nuclear stuf. Number two will go to the Netherlands for the Lofar project. This is a 300 kilometer diameter radio telescope that observes at low frequencies (up to 250 MHz). It constists of thousands of small antennas spread across half the country. Their signals will be interferometrically combined to form the images (compare e.g. to the VLA). Blue Gene will be used to combine all the signals in real time, I believe the total bandwidth from the antennas is some terabyte/sec.

If this will ever get funded (they recently got some money to make first studies) it will be a telescope the size of half the Netherlands. This is of course not a filled aperture, but a sparse one operating at very low frequencies (10-250 MHz, on both sides of the FM frequencies). It will consist of some hundred small "antenna parks" spread around the country and uses a lot of computer power to generate images. It could be a precursor for SKA.