Breakthrough Listen: one year on

Humanity has pondered for centuries whether intelligent life exists beyond Earth. One project currently searching the stars is Breakthrough Listen, which achieved first light a year ago this month. Anton Agejev finds out how the project is progressing.

ESO Photo Ambassador Babak Tafreshi snapped this remarkable image of the antennas of the Atacama Large Millimeter/submillimeter Array (ALMA), set against the splendour of the Milky Way. The richness of the sky in this picture attests to the unsurpassed conditions for astronomy on the 5000-metre-high Chajnantor plateau in Chile’s Atacama region. This view shows the constellations of Carina (The Keel) and Vela (The Sails). The dark, wispy dust clouds of the Milky Way streak from middle top left to middle bottom right. The bright orange star in the upper left is Suhail in Vela, while the similarly orange star in the upper middle is Avior, in Carina. Of the three bright blue stars that form an “L” near these stars, the left two belong to Vela, and the right one to Carina. And exactly in the centre of the image below these stars gleams the pink glow of the Carina Nebula (eso1208). ESO, the European partner in ALMA, is providing 25 of the 66 antennas that will make up the completed telescope. The two antennas closest to the camera, on which the careful viewer can find the markings “DA-43” and “DA-41”, are examples of these European antennas. Construction of the full ALMA array will be completed in 2013, but the telescope is already making scientific observations with a partial array of antennas. Babak Tafreshi is founder of The World At Night, a programme to create and exhibit a collection of stunning photographs and time-lapse videos of the world’s most beautiful and historic sites against a night-time backdrop of stars, planets and celestial events. ALMA, an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ALMA construction and operations are led on behalf of Europe by ESO, on behalf of North America by the National Radio Astronomy Observatory (NRAO), and on behalf of East Asia by the National Astronomical Observatory of Japan (NAOJ). The Joint ALMA Observatory (JAO) prov

The antennas of ESO’s Atacama Large Millimeter/submillimeter Array in Chile, set against the backdrop of the Milky Way. Image Credit: ESO/B. Tafreshi (twanight.org)

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Two possibilities exist: Either we are alone in the Universe or we are not. Both are equally terrifying.
Arthur C. Clarke

The search for extraterrestrial intelligence (SETI) is concerned with looking for artificial signals in space in the hope of discovering extra-terrestrial civilisations outside of our Solar System.

Scientists have been looking and listening for artificial signals in space since the 1960s, when astrophysicist Frank Drake conducted the first ever SETI search.

The field is now more alive than ever, as evidenced by projects like Breakthrough Listen, founded by Yuri Milner and supported by scientists such as Stephen Hawking.

The project is paving the way for discovering life outside our Solar System in the hope of catching a glimpse of an intelligent civilisation.

Hello? Anyone out there?

The project will span 10 years and search over one million stars using radio and optical telescopes (most artificial signals are transmitted through radio or optical), as well as utilising resources that have not been used previously in other SETI programmes.

With work having begun in January 2016, Breakthrough Listen has already collected petabytes of data (one petabyte being equivalent to the data stored on 223,000 DVDs) as a result of its aim to observe in millions of different frequency channels.

“One thing that is already being done by the project is to get time on the radio telescopes at Green Bank and Parkes observatories, and use the special purpose hardware that is available on them to search for narrowband signals,” says Professor Martin Rees, Advisory Member for the Breakthrough Listen project.

“Breakthrough Listen will allow us to do a much deeper and more systematic search than ever before.”

Astronomers involved in the project are listening out for messages from the 100 closest galaxies to us, using instruments 50 times more sensitive than existing SETI telescopes.

The project will also be able to cover 10 times more of the sky than previous programmes using radio surveys, as well as cover five times more of the radio spectrum, and conduct it 100 times faster.

The radio telescope at Green Bank Observatory has been used under the Breakthrough Listen project. (Credit: NRAO/NSF)
The radio telescope at Green Bank Observatory has been used under the Breakthrough Listen project. (Credit: NRAO/NSF)

Constantly having to strike a balance in their methods of using radio to look at nearby stars, or optics to search extragalactically, the project’s astronomers must adapt to cover all possible corners of space.

A narrowband optical pulse (such as that of an emitted laser) could indicate signs of alien technology.

The Lick Observatory in California is currently being used to conduct searches for optical flashes that could indicate emitted light from alien sources, with the possibility of doing an all-sky survey.

Using this method, astronomers could theoretically detect the energy of a normal household light bulb from 40 trillion kilometres away.

They are also using radio telescopes to look for signals, such as the Parkes Observatory in Australia and the Green Bank Observatory in the US.

Using radio, it is possible to locate extra-terrestrial signals much more easily due to its repetitive nature and narrow bandwidths.

Astronomers working on the project are always trying to vary their instrumentation use.

“Discussions are ongoing to be able to conduct a programme at the MeerKAT Array, which would be able to receive 400 beams simultaneously [a beam is angular region of sensitivity, matching the area in the sky], and is really the optimum telescope that would cover the southern hemisphere,” says Professor Rees.

“A lot of the success will depend on the group at the University of Berkeley California that has been developing elaborate hardware for multiband analysis.”

With plans to be in service by 2017, the MeerKAT array will be the largest and most sensitive radio telescope in the southern hemisphere. (Credit: Mike Peel - www.mikepeel.net)
With plans to be in service by 2017, the MeerKAT array will be the largest and most sensitive radio telescope in the southern hemisphere. (Credit: Mike Peel – www.mikepeel.net)

The first batch of collected data was released in April 2016, and since then there have been thousands of terabytes more.

The plan is to break down the data into smaller chunks and then allow the public to participate in processing it.

This idea is similar to the SETI@Home project that allows volunteers to download software onto their computers that processes data collected by astronomers, even while the computer is not being used.

Hope for the Future

With technology advancing at such an incredible pace, humanity has already begun to leave the comfort of Earth to explore the Universe.

Even though the SETI field is a small area of research, astronomers feel it is worth investing in, as discovering intelligent life outside of our Solar System would be revolutionary, allowing us to delve into a new era for mankind.

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“In the deepest sense the search for extraterrestrial intelligence is a search for ourselves” – Carl Sagan (Credit: ESO/José Francisco Salgado)
“In the deepest sense the search for extraterrestrial intelligence is a search for ourselves” – Carl Sagan (Credit: ESO/José Francisco Salgado)

The search so far

In the past, there have been many programmes established in the SETI field. Here are some of the most notable projects conducted.

Project Ozma

Known as the first ever search for extra-terrestrial life, Project Ozma paved the way for SETI research.
Known as the first ever search for extra-terrestrial life, Project Ozma paved the way for SETI research.

When: April – July 1960

Where: National Radio Astronomy Observatory, USA

Method: Observed at the 1.42 GHz frequency known as the ‘water hole’, as there is minimum interference from natural cosmic noise, and looked at Sun-like stars Tau Ceti and Eridani

Equipment: Conducted with the 26m Howard E. Tatel radio telescope

Known for: Paving the way for SETI research

Ohio State University SETI Programme

The SETI programme at Ohio State University was one of the longest running searches for ETI. (Credit: Bigear.org/NAAPO)
The SETI programme at Ohio State University was one of the longest running searches for ETI. (Credit: Bigear.org/NAAPO)

When: 1973-1995

Where: Perkins Observatory, US

Method: Observed at 1.42 GHz (‘water hole’) frequency conducting sky surveys

Equipment: ‘Big Ear’ radio telescope (equivalent to 52.5m dish)

Known for: The ‘Wow!’ signal, which was a strong radio signal that bore marks of extra-terrestrial origin

SERENDIP (Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations)

The SERENDIP instrument is installed in telescopes all around the world. (Credit: Laura Spitler/Cornell University - astro.cornell.edu/~lspitler/research.htm)
The SERENDIP instrument is installed in telescopes all around the world. (Credit: Laura Spitler/Cornell University – astro.cornell.edu/~lspitler/research.htm)

When: 1979 – Present

Where: Various locations around the world

Method: Records and measures spectra from 400 MHz to 1.42 GHz. Distinguishes potential extra-terrestrial signals and acts as a ‘piggy-back’ by analysing deep-space radio telescope data as astronomers are conducting research on the telescopes

Equipment: SERENDIP VI (current) spectrometer receiver

Known for: Finding 400 suspicious signals

Project Phoenix (1995 – 2004)

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The Arecibo radio telescope, used from 1998-2004. (Credit: Seth Shostak/SETI Institue)

When: 1995 – 2004

Where: Parkes Observatory, Australia (1995 – 1996) / Green Bank Observatory, USA (1996 – 1998) / Arecibo Observatory, USA (1998 – 2004)

Method: Observed between 1.2 GHz and 3 GHz. Scanned 800 stars within 200 lightyears of each other

Equipment: 64m radio telescope at Parkes Observatory / 43m radio telescope at Green Bank Observatory / 133m radio telescope at Arecibo Observatory

Known for: Enabling scientists to conclude that our Solar System is quiet, as no signs of extra-terrestrial life were found

Allen Telescope Array (ATA) (2007 – Present)

Plans are in place to expand the ATA to 350 radio dishes. (Credit: SETI Institute)
Plans are in place to expand the ATA to 350 radio dishes. (Credit: SETI Institute)

When: 2007 – Present

Where: Hat Creek Observatory, USA

Method: Observations made between 500 MH – 11.2 GHz. Studies many areas of the sky at once, including over one million nearby stars

Equipment: 42 x 6.1m radio dishes, with plans to expand to 350

Known for: More than two million signals have been followed up and classified