When Lofar Meets Stella 123
Roland Piquepaille writes "The LOFAR (Low Frequency Array) telescope is a new IT radio-telescope which will use about 20,000 simple radio antennae when it's completed in 2008. At this time, it will cover an area with a diameter of 360 kilometers centered over the Netherlands. Its small radio antennae will detect radio wavelengths up to 30 meters, and because the ionosphere can bend some of these radio waves, the Lofar images might be somewhat blurry. So all the information captured by these antennae will be digitized and sent to a computing facility at a rate of 22 terabits/second today, and almost 50 terabits/second in 2010. This is the reason why Lofar needs Stella, an IBM supercomputer installed recently in Groningen, also in the Netherlands, to process signals from up to 13 billion light years from Earth. Stella consists of 12,000 PowerPC microprocessors and has a computing power of 27.4 teraflops. This overview contains more details and a picture about the Lofar-Stella interaction."
Hmm. (Score:2)
Re:Hmm. (Score:2)
They should just drop the guise and name the array "Harold".
OOooo (Score:5, Funny)
I love it when slashdot talks dirty.
Re:OOooo (Score:4, Funny)
"she held his throbbing baud close to hers and their pulse quickened 9600, 56k, 128.. faster,faster.. 22 terabits! Oh MY GOD! 50 terabits per second! Data erupting everywhere."
excuse me, I'm just going to go wash up..
Re:OOooo (Score:2)
Ewwww
From Piqy's stupid Blogvertisement (Score:5, Informative)
When Lofar Meets Stella
The LOFAR (Low Frequency Array) telescope is a new IT radio-telescope which will use about 20,000 simple radio antennae when it's completed in 2008. At this time, it will cover an area with a diameter of 360 kilometers centered over the Netherlands. Its small radio antennae will detect radio wavelengths up to 30 meters, and because the ionosphere can bend some of these radio waves, the Lofar images might be somewhat blurry. So all the information captured by these antennae will be digitized and sent to a computing facility at a rate of 22 terabits/second today, and almost 50 terabits/second in 2010. This is the reason why Lofar needs Stella, an IBM supercomputer installed recently in Groningen, also in the Netherlands, to process signals from up to 13 billion light years from Earth. Stella consists of 12,000 PowerPC microprocessors and has a computing power of 27.4 teraflops. Read more...
Let's start with the opening paragraphs of an article from New Scientist, "Huge radio telescope boasts supercomputer brain."
One of the world's most powerful supercomputers is to be the brain of a revolutionary new radio telescope called LOFAR. The telescope will look back to the time of the very first stars, map our galaxy's magnetic field and perhaps discover the mysterious sources of high-energy cosmic rays.
Instead of one large rigid dish, LOFAR will use thousands of simple radio antennae. Their signals will be woven together at the University of Groningen in the Netherlands by STELLA, the new supercomputer, which was launched on Tuesday and is unofficially ranked as the third most powerful on the planet.
LOFAR needs its own supercomputer because it aims to detect radio wavelengths of up to 30 metres. Such long-wave radio images are blurry, and the only way to make them sharper is to build a vast array of detectors spread over hundreds of kilometres.
Now, let's move to the General Information section of the LOFAR website for more specific information.
LOFAR is the first telescope of this new sort, using an array of simple omni-directional antennas instead of mechanical signal processing with a dish antenna. The electronic signals from the antennas are digitised, transported to a central digital processor, and combined in software to emulate a conventional antenna. The cost is dominated by the cost of electronics and will follow Moore's law, becoming cheaper with time and allowing increasingly large telescopes to be built.
So LOFAR is an IT-telescope. 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).
Below is a general diagram of the LOFAR-STELLA interaction picked from the System section of the LOFAR website (Credit: LOFAR).
A diagram of the LOFAR environment
Details are scarce about the STELLA supercomputer, built by IBM using some of its Blue Gene/L technology. Reuters gave some information last week in "Europe's Biggest Supercomputer Eavesdrops on Stars."
Running on 12,000 PowerPC microprocessors, the computer can execute 27.4 Teraflops, or 27.4 trillion floating-point operations, per second.
The new computer will consume 150 Kilowatts of power -- the equivalent of 2,500 60-watt light bulbs -- which is considered economical for a supercomputer, IBM said.
If you understand Dutch, you also can read this news release about this supercomputer.
Now we have to wait to see if the happy couple of Lofar and Stella can produce images as beautiful as Hubble gave us during the last decade.
Sources: Various websites
Re:From Piqy's stupid Blogvertisement (Score:3, Interesting)
When Roland meets Slashdot... (Score:3, Insightful)
P.S. stop posting prostoalex submissions, too.
Re:When Roland meets Slashdot... (Score:3, Insightful)
So what is it about Roland's submissions that people find objectionable? If they're paid placements I can understand, but if they're simply articles which are interesting enough to get posted then where's the harm?
Re:When Roland meets Slashdot... (Score:3, Informative)
Oh, and more ads, which make the purpose of Roland submissions appear to be simply to divert readers to his site on the way to the REAL news, just for those ad dollars.
Re:When Roland meets Slashdot... (Score:2)
Like Slashdot.
Re:When Roland meets Slashdot... (Score:2)
Re:When Roland meets Slashdot... (Score:2)
Re:When Roland meets Slashdot... (Score:2)
In this case, the blog bullshit consists of quotes from and a link to New Scientist, ditto for the LOFAR website itself along with a diagram of the LOFAR-STELLA interaction, a link to and a quote from a Reuters article, and a link to a news release in Dutch. The length of the article wouldn't fit given slashdot's typical summary size, not to mention that
Re:When Roland meets Slashdot... (Score:2)
Re:When Roland meets Slashdot... (Score:2)
That's why I asked for clarification.
I don't care who it's submitted by, as long as what is submitted is interesting and provides the links to the original material in question.
I don't know about you, but I found Roland's article interesting and it did provide links to the original material so I could read more in-depth should the topic be of interest.
Despite what you might think, some online news sites do in fact write compelling, original articles that people en
Re:When Roland meets Slashdot... (Score:2)
To me, it sounds like you're complaining that Roland does what slashdot does -- presents stories and pays for it with ads.
Re:When Roland meets Slashdot... (Score:3, Insightful)
Re:When Roland meets Slashdot... (Score:2)
Finally... (Score:2, Funny)
high taxes, weird food, Metric system (Score:1, Funny)
Re:high taxes, weird food, Metric system (Score:2)
A Telescope Named Desire (Score:4, Funny)
Stella and Blue Gene (Score:2, Informative)
Details are plenty since what IBM gave to the project is a couple of racks of BlueGene so everything applies, scaled proportionately.
Here are some details: http://www.research.ibm.com/bluegene/ [ibm.com] and http://www.llnl.gov/asci/platforms/bluegenel/ [llnl.gov]
IBM BlueGene (Score:5, Informative)
You cross-compile your application on a power4/5 linux box, and then submit it to the system.. they reduced the computational aspect to it's most basic components.. CPU/FPU, memory, and MPI interconnect..
compute nodes don't even have ethernet or drive controlers... all I/O is handled by another specialized I/O node, which provides data over one of the two MPI interconnects.
Uh.... (Score:1)
I thought it came with a 6502 and a TIA...
Stella (Score:2, Interesting)
Re:Stella (Score:2)
Who needs editors anyways (Score:2, Insightful)
2) The blurb was written by some third grader, wasn't it?
IT radio-telescope? What is IT? Radio is an adjective, there's no need to hyphenate radio telescope.
"At this time"? Now? I thought it won't be completed until 2008?
We detect radio waves, not wavelengths.
"the Lofar images might be somewhat blurry"? Images? Since when do we get images from radio telescopes?
They're obviously not sending data at 22 terabits/sec today, since th
Re:Who needs editors anyways (Score:1, Interesting)
Ummm... Actually radio telescopes have been producing high quality images for years. In terms of sharpness (angular resolution) these images can be even better than the hubble. There are plenty of examples at www.nrao.edu.
For example:
http://www.nrao.edu/imagegallery/php/level3.php?id =5 [nrao.edu]
Re:Who needs editors anyways (Score:2)
Re:Who needs editors anyways (Score:2)
Yes, but according to websters, it's also a noun and even a verb.
Main Entry: 2radio
Function: noun
Inflected Form(s): plural radios
Etymology: short for radiotelegraphy
1 a : the wireless transmission and reception of electric impulses or signals by means of electromagnetic waves b : the use of these waves for the wireless transmission of electric impulses into which sound is converted
Main Entry: 3radio
Funct
Re:Moron! (Score:1)
Yes we do! They specially train radio astronomers to listen to it. Did you know supernovae sound like violins?
Rumors (Score:2)
I am Lofar of the Dish People! (Score:2, Funny)
aperture synthesis array (Score:4, Informative)
It's a big mess-O-sensors spread over a wide area.
Radio, seismic, atmospheric pressure, and "other".
With the big iron computer it will be possible to play around with all sorts of spatio-temporal signal processing. This has been done with optical telescopes to remove 'twinkles', SA-RADAR and SA-SONAR, and most intensively in oil exploration where 2-D arrays of seismic sensors coupled with 2-D arrays of seismic sources are used in oil exploration. The neat thing, just liek in oil exploration, is that the data from the different sensors can be looked at for correlations. air-pressure, seismic, and radio data all recorded around a significant geophysical event. Yes, I knwo this is 'fishing science', bu tit is fun...
Mandrake? (Score:2)
(I know, that is spelled Lothar, but still... :-) )
Re:Mandrake? (Score:1)
Age of Universe (Score:1)
Without veering too far off topic, I have a philosophical/mathematical question which always pops to mind when the age of the universe is mentioned:
If the universe were to continue to expand forever, giving it an infinite timespan, isn't it statistically impossible that we would exist to observe it a non-infinite time period from its birth? That is, any random year to exist fro
Re:Age of Universe (Score:2)
> forever, giving it an infinite timespan, isn't
> it statistically impossible that we would exist
> to observe it a non-infinite time period from
> its birth?
If space is infinite the distance from me to the end of the universe is infinite. Isn't it then statistically impossible that you would exist at a non-infinite distance from me?
> Extrapolating this, can't we make some
> probabilistic prediction as to the future age of
> the universe?
Yo
Re:Age of Universe (Score:1, Insightful)
Next to that you arn't using the statistics correctly. The real question should be, what is the chance intelligent life could come into existence in this universe o
Re:Age of Universe (Score:1)
Re:Sounds pretty neat (Score:2)
Besides, almost half of the array will be in Germany.
Human Pawns (Score:2)
Oops, wrong Stella (Score:2)
Re:Antennas, not Antennae (Score:1)
I can illustrate the relation too! (Score:2)
StellaLofar
OK folks, there we have it!
A brain the size of a planet... (Score:2)
LOFAR of the hill people! (Score:2, Funny)
We speak of many things! Detecting radio wavelengths! Fire! The weakness of women!
Sorry, That was the first thing I thought of when I read LOFAR meets stella
Re:LOFAR of the hill people! (Score:2)
Re:LOFAR of the hill people! (Score:1)
Re:LOFAR of the hill people! (Score:2)
Hubble (Score:2)
It sounds like this is going to be used largely for planet hunting, something the Hubble isn't very spectacular with.
Re:Hubble (Score:1)
Re:Hubble (Score:2)
Am I wrong in thinking that radio and infrared telescopes are gaining serious momentum, leaving the Hubble to show its age?
Re:Hubble (Score:1)
Am I wrong in thi
Re:Hubble (Score:1)
more than only for 20.000 telescopes (Score:1)
Apperently they have a few flops to spare
Re:more than only for 20.000 telescopes (Score:2)
What?! Do you consider a telescope something other than a sensor? I suppose it could be seen as a tool for keeping astronomers up at night. Or a way of transferring money from the general public to scientists. Um.. But I definitely consider a telescope to be a sensor.
Supercomputer (Score:5, Insightful)
Even though this telescope will not be placed in the most densily populated area, the Netherlands is hardly the place to go looking for 350 KM^2 of land to put a radio telescope on. 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.
Anyway, I'm buying stock in the storage business.
Re:Supercomputer (Score:1)
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 r [lofar.org]
Re:Supercomputer (Score:2)
> more economic, consider that this thing is being
> built where the astronomers are.
We have this thing called the "Internet". Astronomers have not found it necessary to be near their telescopes for many years.
I suspect that, like most large government-funded projects, it is being built where the constituents are.
Re:Supercomputer (Score:1)
One 'snapshot' image made with the Lofar test site is about 4 Gb. When Lofar is fully operational this will be many, many times bigger.. you do not want to send those files back and forth over the Internet ;)
A glass fiber network is being built in the area to be able to get the data to the supercomputer.
There is also the difference between radio and optical telescopes: radio tel
Re:Supercomputer (Score:2)
Only because there are more optical telescopes than radio ones. Both radio and optical professional telescopes tend to be far away from large population centers to avoid manmade interference (streetlights, etc., for optical, a wide variety of electronics for radio). LOFAR, being in a heavily populated a
Re:Supercomputer (Score:2)
Considering that it will take years to develop and optimize the software - no, I don't find it strange at all.
What they don't talk about.... (Score:4, Interesting)
It might sound impressive, but it's a stupid idea. 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. Especially if the RFI gets so bad that it saturates the receiver front-ends.
LOFAR (my office mate worked on it) used to be an international collaboration, but it broke a apart because the Dutch insisted it be build in their country, rather than in some place more sensible, like Western Australia.
Re:What they don't talk about.... (Score:4, Informative)
usual quote from Scotty re physics, immutability (Score:2)
Re:usual quote from Scotty re physics, immutabilit (Score:2, Insightful)
You'd really like to have a directional antenna to block out signals that are not coming from the sky.
That's why it's a 'phased array'. The concept is pretty simple: if a signal is coming from a certain direction, it will arrive at antenna A a fraction of a second earlier than at antenna B. LOFAR measures the incoming signals and their phase at all the antennae, and then lets software 'untangle' this information to reconstruct
Re:usual quote from Scotty re physics, immutabilit (Score:2)
> large enough to just ignore rusty fence wire
How do you figure that when such pieces of wire are often meters to kilometers in length?
You are correct in that such spurious radiation won't be a serious problem, though.
Re:usual quote from Scotty re physics, immutabilit (Score:1)
I know that sheep aren't a problem though..
Re:usual quote from Scotty re physics, immutabilit (Score:2)
Re:usual quote from Scotty re physics, immutabilit (Score:1)
What I was trying to say is that the sources of noise, usually on the horizon, can be picked out later and ignored. No, it does nothing about saturation etc. like you said, but wouldn't directional antennae have the same problem? There will always be a few noisy frequency bands where no observations can be done, but there are enough frequencies left to give science something
I worked on a functional demonstration for LOFAR (Score:2)
I worked on a functional small-scale phased array antenna for the LOFAR project. It was sized to work around 900 MHz, and we could track a portable landline phone with it. We only used the parallel port to transfer the info from the antenna to the PC, and it was just a commodity PC, but it worked, and it was neat. We used seven individual antennas.
-Jesse
Re:Money!! (Score:2)
Does it really matter if you adblock it? I have www.primidi.com blocked completely and when I click it only loads its text, not anything ad-like.
Or am I naive to think that's not good enough to stop letting someone use slashdot for making profit?
Re:I dare you to read this! (Score:1, Funny)
(If you don't get it, sound it out phonetically.)
--dg
Re:fp hom0 (Score:1)
Re:fp hom0 (Score:1)