New SETI program to scan for low-frequency messages

Posted by Emma Woollacott

A new radio astronomy facility has started mapping the universe at very low wavelengths and looking for messages from other civilisations.

The Low Frequency Array (LOFAR) will also be used to investigate the first stars and mini-black holes that emerged when the Universe was only 500,000 years old.

The first phase of the SETI program will study how contamination from terrestrial transmitters can be eliminated before moving on to an extended program of looking at nearby stars.

"LOFAR will scan nearby stars searching for radio emissions which could only be produced by artificial means - a sign that there is a civilisation there and that we are not alone," says SETI's Dr Alan Penny.

"Previous investigations of these stars have concentrated on higher frequencies but, as we do not know at which frequencies an extraterrestrial civilisation might choose to emit radio waves, LOFAR will fill an important gap in the search."

"It's exactly 50 years since the first SETI observations were conducted by Frank Drake. LOFAR will expand on conventional SETI search strategies by observing in a very different frequency domain and with a huge field of view. The prospects are intriguing to say the least!” said Professor Mike Garrett, the Director General of ASTRON.

Astronomers also plan to use LOFAR to study the many cosmic rays that impact the Earth every day, pulsars and the magnetic field within our own and nearby galaxies. It will also compile a census of billions of radio emitting galaxies from the very early universe.

"Our first images show the emission from radio galaxies with jets of material that are ejected at relativistic speeds from the central supermassive black hole, ending with hot-spots as the material clumps together," said Dr John McKean, of the Netherlands Institute for Radio Astronomy (ASTRON). "The image quality from LOFAR is just amazing, compared to telescopes we have been using up until now."
 
When completed, the telescope will consist of at least 44 independent stations spread across the Netherlands, Germany, Sweden, France and the UK. Working at low frequencies means the telescope has to be very large to see fine detail, and this is achieved by having the stations spread over hundreds of miles. 

“The amazing sensitivity and resolution of LOFAR is giving us an unprecedented view of how our Universe has evolved over billions of years. The low-frequency part of the electromagnetic spectrum has never been looked at to the level of detail that LOFAR will allow; we are expecting to find new types of galaxies that have just never been seen before,” said Dr McKean.