Software Telescope

An anonymous reader writes "The BBC News is running the story 'Pyramid power' probes universe which is about LOFAR's software telescope for radio astronomy. The heart of the system is a IBM Blue Gene which processes data from an array of simple pyramidal radio antennae. The array of antennae are also multitasking in the fields of geophysics and agriculture."

Comments

LOFAR is going to be exciting

[karvind]

Our earlier Slashdat stories on LOFAR: a consortium between ASTRON (The Netherlands), NRL (USA) and MIT/Haystack (USA).:

When Lofar Meets Stella

350 KM Diameter Radio Telescope Array

I was talking to a professor in astronomy here and he mentioned about some of the conflicts between US and Europe regarding the plan. That is one of the reasons why US is also working on Square Kilometer Array. LOFAR imaging telescope are designed for the 10-240 MHz frequency range where as SKA will cover 0.15-20GHz or higher. Hopefully the two efforts will complement each other.

Re:LOFAR is going to be exciting

[steve_vmwx]

Hmmm. Wasn't Euro v's USA. It was the Dutch v's everyone else.

LOFAR was supposed to be the international forerunner to SKA for a lot of the tech.

Western Australia won the site selection. Dutch government said "if you build it here we'll throw in a bucket load of cash". Dutch reps took the bird in the hand (kind of understandable given the global spending habits of governments on peaceful science).

Everyone else in the original LOFAR weren't (and still aren't) too happy.

Still... it's a nice piece of kit.

SKA development continues. WA is again up for site selection. Speaking as an Oz astronomer I'm hopefull. It's a great site for radio astronomy.

For the person who asked, the antenna design is a folded dipole. Google it :)

Cheers
Stevo

Re:Why can't we distribute this work?

[karvind]

From LOFAR website:

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).

Re:Why can't we distribute this work?

[IWannaBeAnAC]

For this project, it is the huge rate of incoming data that is the problem. They must process it immedately, as it would take a huge amount of storage to keep even a few hours worth of data. Anyway, the processing will involve determining the correlations between data from different sensors, which probably requires lots of communication. Both these points are big negatives for a distributed.net computation.

Of course, you would know this if you had RTFA before you posted...

Re:Why isn't there any tech info on the antenna?

[reddish]

The antennas are pyramid shaped because each of those pyramids actually contains two dipole antennas, to capture the EM field in two perpendicular polarisations. (I am involved in the project so trust me on this one ;-))