Breakthrough Listen

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The Green Bank Telescope is one of the radio telescopes used by the project. GBT.png
The Green Bank Telescope is one of the radio telescopes used by the project.

Breakthrough Listen is a project to search for intelligent extraterrestrial communications in the Universe. [1] [2] With $100 million in funding and thousands of hours of dedicated telescope time on state-of-the-art facilities, [3] it is the most comprehensive search for alien communications to date. [1] [2] The project began in January 2016, and is expected to continue for 10 years. [4] It is a component of Yuri Milner's Breakthrough Initiatives program. The science program for Breakthrough Listen is based at Berkeley SETI Research Center, [5] [6] located in the Astronomy Department [7] at the University of California, Berkeley.

Contents

The project uses radio wave observations from the Green Bank Observatory and the Parkes Observatory, and visible light observations from the Automated Planet Finder. [8] Targets for the project include one million nearby stars and the centers of 100 galaxies. All data generated from the project are available to the public, and SETI@Home (BOINC) is used for some of the data analysis. The first results were published in April 2017, with further updates expected every 6 months. [6]

Overview

The project aims to discover signs of extraterrestrial civilizations by searching stars and galaxies for radio signals and laser transmissions. The search for radio signals is carried out on the Green Bank Telescope in the Northern Hemisphere and the Parkes Telescope in the Southern Hemisphere. The Green Bank Telescope is the world's largest steerable radio telescope, and the Parkes Telescope is the second-largest steerable radio telescope in the Southern Hemisphere. [9] [10]

Together, the radio telescopes will cover ten times more sky than previous searches and scan the entire 1-to-10 GHz range, the so-called "quiet zone" in the spectrum where radio waves are unobscured by cosmic sources or Earth's atmosphere. [11]

The radio telescopes are sensitive enough to detect "Earth-leakage" levels of radio transmission from stars within 5 parsecs, [4] and can detect a transmitter of the same power as a common aircraft radar from the 1,000 nearest stars. [12] The Green Bank Telescope began operations in January 2016, and the Parkes Telescope from October 2016. [4] The FAST radiotelescope in China also joined forces in October 2016 with the Breakthrough Initiatives to launch a coordinated search, including the rapid sharing of promising new signals for additional observation and analysis. [13]

The search for optical laser transmissions is carried out by the Automated Planet Finder of Lick Observatory. [14] The telescope has the sensitivity to detect a 100 watt laser from a star 25 trillion miles (4.25 light years) away. [12]

Announcement

Physicist Stephen Hawking was among the scientists who co-signed an open letter of support for Breakthrough Listen. Stephen Hawking in Cambridge.jpg
Physicist Stephen Hawking was among the scientists who co-signed an open letter of support for Breakthrough Listen.

Breakthrough Listen was announced to the public on July 20, 2015 (the anniversary of the Apollo 11 Moon landing) by Milner at London's Royal Society. The event was flanked by scientists such as Frank Drake, who is known for the Drake equation that estimates the number of detectable alien civilizations, and Geoff Marcy, an astronomer who has helped find hundreds of exoplanets. [15] The announcement included an open letter co-signed by multiple scientists, including physicist Stephen Hawking, expressing support for an intensified search for alien life. [1] [16] During the public launch, Hawking said:

In an infinite Universe, there must be other life. There is no bigger question. It is time to commit to finding the answer. [1]

Significance

The project is the most comprehensive search for alien communications to date. [1] It is estimated that the project will generate as much data in one day as previous SETI projects generated in one year. [1] Compared to previous programs, the radio surveys cover 10 times more of the sky, at least 5 times more of the radio spectrum, and work 100 times faster. [14] The optical laser survey is also the deepest and broadest search in history. [14]

Andrew Siemion, director of the Berkeley SETI Research Center at the University of California, Berkeley, describes that "We would typically get 24–36 hours on a telescope per year, but now we'll have thousands of hours per year on the best instruments...It's difficult to overstate how big this is. It's a revolution." [17]

Targets

As of April 2016, the targets for the radio search with the Green Bank Radio Telescope in the Northern Hemisphere include the following: [4]

The Parkes Radio Telescope will cover similar targets in the Southern Hemisphere from 1–4 GHz, and also the galactic plane and center. [4]

The targets for the Automated Planet Finder will closely match those of the Green Bank radio search, with small adjustments due to the telescope's much smaller field of view. [4]

While the telescopes are observing, the current targets of the Green Bank Radio Telescope and the Automated Planet Finder can be viewed live at the Berkeley Seti Research Center.[ citation needed ]

In January 2017, the project published its initial targets, which are the 60 nearest stars and a further 1649 stars which are the closest representatives of each spectral type. [18] The initial targets also include 123 galaxies which cover all morphological types of galaxies. [18]

In October 2019 it was announced that Breakthrough Listen will collaborate with scientist from NASA's Transiting Exoplanet Survey Satellite (TESS) team. Over a thousand new planets found by TESS will be scanned for technosignatures. The search will use Listen's primary facilities (Green Bank and Parkes Telescopes, MeerKAT, and the Automated Planet Finder) as well as partner facilities (including VERITAS, NenuFAR, FAST, the Murchison Widefield Array, LOFAR stations in Ireland and Sweden, Jodrell Bank Observatory, e-MERLIN, Keck Observatory, Sardinia Radio Telescope, along with the Allen Telescope Array). In addition to targeting of TESS planets with Listen facilities, the TESS lightcurves themselves will be searched for anomalies, for example caused by megastructures. [19] [20]

Breakthrough Listen Exotica Catalog

Breakthrough Listen Exotica Catalog is a list of 700 targets that were chosen "to include "one of everything" in the observed Universe – ranging from comets to galaxies, from mundane objects to the most rare and violent celestial phenomena". [21] [22] [23]

There are four types of targets in the catalog: [21]

  1. "Prototypes: a list containing at least one example of every known kind of celestial object (apart from those too transient to present realistic observation targets). Planets and moons, stars at every point of their life cycle, galaxies big and small, serene star clusters and blazing quasars, and more are all included in the list."
  2. "Superlatives: objects with the most extreme properties. These include examples like the hottest planet, stars with unusually high or low metal content, the most distant quasar and fastest-spinning pulsar, and the densest galaxy."
  3. "Anomalies: enigmatic targets whose behavior is currently not satisfactorily explained. For instance, the famous "Tabby's Star" with its bizarre dimming behavior; ʻOumuamua – the interstellar object that passed near Earth in 2017; unexplained optical pulses that last mere nanoseconds; and stars with excess infrared radiation that could conceivably be explained as waste heat from alien megastructures."
  4. A control sample of sources not expected to produce positive results.

Data processing

Analyzing radio observations for possible signals requires intensive data analysis to cover all of the possible signal types. To carry out an in-depth search, the data recorder at the Green Bank telescope has been significantly upgraded. [24] The system records 6 GHz of bandwidth at 24GB of data per second, making it among the highest data rate recording systems in radio astronomy, and there is a plan to double its capabilities in the near future. [24] Once this data has been recorded, it is analysed for signals using a computing cluster with 64 GTX 1080 GPUs. [24] The raw data is reduced to a lower resolution to allow long-term storage, but even this reduced data totals approximately 1 petabyte per year. [25]

All data generated from Breakthrough Listen project will be open to the public. [26] The data is uploaded on the initiative's Open Data Archive, where any user can download it for software analysis. Breakthrough Initiatives are developing open source software to assist users in understanding and analyzing the data, which are available on GitHub under UCBerkeleySETI. [26]

The data is also processed by the SETI@home (BOINC) volunteer computer network, with the first batch of data being made available to SETI@home in April 2016. [4]

Funding

The project is funded with $100 million from Yuri Milner. [27] One third of this funding will be used to purchase telescope time. [28] So far, the project has signed contracts for around 20 percent of the time on the Green Bank Telescope for the next five years, and 25 percent of the time on the Parkes Telescope. [9] [29] Another third will be used for the development of new equipment to receive and process potential signals, [28] and the final third will be used to hire astronomy staff. [30]

Project leadership

Among the projects leaders are:[ citation needed ]

Results

The project has begun at lower frequencies as these have a lower frequency range which is easier to record and process, and plans eventually to observe in a wide range of frequencies from 1.15 GHz to 93 GHz. [24]

See also

Related Research Articles

The search for extraterrestrial intelligence (SETI) is a collective term for scientific searches for intelligent extraterrestrial life, for example, monitoring electromagnetic radiation for signs of transmissions from civilizations on other planets.

<span class="mw-page-title-main">Frank Drake</span> American astronomer and astrophysicist (1930–2022)

Frank Donald Drake was an American astrophysicist and astrobiologist.

<span class="mw-page-title-main">SETI@home</span> BOINC based volunteer computing project searching for signs of extraterrestrial intelligence

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<span class="mw-page-title-main">Green Bank Telescope</span> Radio telescope in Green Bank, WV, US

The Robert C. Byrd Green Bank Telescope (GBT) in Green Bank, West Virginia, US is the world's largest fully steerable radio telescope, surpassing the Effelsberg 100-m Radio Telescope in Germany. The Green Bank site was part of the National Radio Astronomy Observatory (NRAO) until September 30, 2016. Since October 1, 2016, the telescope has been operated by the independent Green Bank Observatory. The telescope's name honors the late Senator Robert C. Byrd who represented West Virginia and who pushed the funding of the telescope through Congress.

<span class="mw-page-title-main">Wow! signal</span> 1977 narrowband radio signal from SETI

The Wow! signal was a strong narrowband radio signal detected on August 15, 1977, by Ohio State University's Big Ear radio telescope in the United States, then used to support the search for extraterrestrial intelligence. The signal appeared to come from the direction of the constellation Sagittarius and bore expected hallmarks of extraterrestrial origin.

<span class="mw-page-title-main">Allen Telescope Array</span> Radio telescope array

The Allen Telescope Array (ATA), formerly known as the One Hectare Telescope (1hT), is a radio telescope array dedicated to astronomical observations and a simultaneous search for extraterrestrial intelligence (SETI). The array is situated at the Hat Creek Radio Observatory in Shasta County, 290 miles (470 km) northeast of San Francisco, California.

<span class="mw-page-title-main">Avi Loeb</span> Israeli-American theoretical physicist

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<span class="mw-page-title-main">Automated Planet Finder</span> Robotic optical telescope searching for extrasolar planets

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<span class="mw-page-title-main">Technosignature</span> Property that provides scientific evidence for the presence of technology

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Breakthrough Initiatives is a science-based program founded in 2015 and funded by Julia and Yuri Milner, also of Breakthrough Prize, to search for extraterrestrial intelligence over a span of at least 10 years. The program is divided into multiple projects. Breakthrough Listen will comprise an effort to search over 1,000,000 stars for artificial radio or laser signals. A parallel project called Breakthrough Message is an effort to create a message "representative of humanity and planet Earth". The project Breakthrough Starshot, co-founded with Mark Zuckerberg, aims to send a swarm of probes to the nearest star at about 20% the speed of light. The project Breakthrough Watch aims to identify and characterize Earth-sized, rocky planets around Alpha Centauri and other stars within 20 light years of Earth. Breakthrough plans to send a mission to Saturn's moon Enceladus, in search for life in its warm ocean, and in 2018 signed a partnership agreement with NASA for the project.

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Andrew Patrick Vincent Siemion is an astrophysicist and director of the Berkeley SETI Research Center. His research interests include high energy time-variable celestial phenomena, astronomical instrumentation and the search for extraterrestrial intelligence (SETI). Andrew Siemion is the Principal Investigator for the Breakthrough Listen program.

<span class="mw-page-title-main">HD 164595</span> Star in the constellation of Hercules

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<span class="mw-page-title-main">ʻOumuamua</span> Interstellar object passed near Earth in 2017

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<span class="mw-page-title-main">Berkeley SETI Research Center</span>

The Berkeley SETI Research Center (BSRC) conducts experiments searching for optical and electromagnetic transmissions from intelligent extraterrestrial civilizations. The center is based at the University of California, Berkeley.

<span class="mw-page-title-main">NIROSETI</span> Astronomical program to search for artificial signals

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<span class="mw-page-title-main">BLC1</span> Narrowband radio signal detected in April and May 2019

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<span class="mw-page-title-main">Alberto Caballero (astronomer)</span> Spanish astronomer (born c. 1991)

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<span class="mw-page-title-main">2MASS 19281982-2640123</span> Star in the constellation of Sagittarius

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References

  1. 1 2 3 4 5 6 Merali, Zeeya (20 July 2015). "Search for extraterrestrial intelligence gets a $100-million boost. Russian billionaire Yuri Milner announces most comprehensive hunt for alien life". Nature. 523 (7561). Nature News: 392–3. Bibcode:2015Natur.523..392M. doi: 10.1038/nature.2015.18016 . PMID   26201576.
  2. 1 2 Rundle, Michael (20 July 2015). "$100m Breakthrough Listen is 'largest ever' search for alien civilisations". Wired . Retrieved 20 July 2015.
  3. ↑ Chethan Kumar (August 31, 2017). "Breakthrough detects 15 radio bursts from dwarf galaxy; might be from 'alien' spacecraft". Times of India.
  4. 1 2 3 4 5 6 7 "Breakthrough Listen Initiative Publicly Sharing Data from Unprecedented Search for Intelligent Life in the Universe". Breakthrough Initiatives. April 12, 2016. Retrieved 2016-04-14.
  5. ↑ "Berkeley SETI". seti.berkeley.edu. Retrieved 2017-09-21.
  6. 1 2 3 4 "Breakthrough Listen Initiative Publishes Initial Results". Breakthrough Initiatives. April 20, 2017. Retrieved 2017-09-21.
  7. ↑ "Breakthrough Listen Initiative – News from Department of Astronomy". astro.berkeley.edu. Retrieved 2017-09-21.
  8. ↑ Sample, Ian (20 July 2015). "Anybody out there? $100m radio wave project to scan far regions for alien life". The Guardian. Retrieved 20 July 2015.
  9. 1 2 "Green Bank Telescope Joins 'Breakthrough Listen' – NRAO: Revealing the Hidden Universe". public.nrao.edu. Retrieved 2016-04-14.
  10. ↑ "Telescopes". Breakthrough Listen. Retrieved 2016-04-14.
  11. ↑ Zhang, Sarah (2015-07-20). "A Russian Tycoon Is Spending $100 Million to Hunt for Aliens". WIRED. Retrieved 2016-04-14.
  12. 1 2 Brodkin, Jon (2015-07-20). "$100 million search for aliens will listen for messages from 100 galaxies". Ars Technica . Retrieved 24 July 2015.
  13. ↑ "National Astronomical Observatories of China, Breakthrough Initiatives Launch Global Collaboration in Search for Intelligent life in the Universe" (Press release). Breakthrough Initiatives. 12 October 2016. Retrieved 2016-10-14– via Astrobiology Web.
  14. 1 2 3 "Listen". Breakthrough Listen. Retrieved 2016-04-14.
  15. ↑ Zhang, Sarah (2015-07-20). "A Russian Tycoon Is Spending $100 Million to Hunt for Aliens". Wired . Retrieved 11 August 2015.
  16. ↑ Vella, Matt (21 July 2015). "Read the Inspiring 'Questions of Existence' Letter from the World's Greatest Thinkers". Time . Retrieved 21 July 2015.
  17. ↑ Merali, Zeeya (2015). "Search for extraterrestrial intelligence gets a $100-million boost". Nature. 523 (7561): 392–393. Bibcode:2015Natur.523..392M. doi: 10.1038/nature.2015.18016 . PMID   26201576.
  18. 1 2 Howard Isaacson; Andrew P. V. Siemion; Geoffrey W. Marcy; Matt Lebofsky; Danny C. Price; et al. (2017). "The Breakthrough Listen Search for Intelligent Life: Target Selection of Nearby Stars and Galaxies". Publications of the Astronomical Society of the Pacific. 129 (975): 054501. arXiv: 1701.06227 . Bibcode:2017PASP..129e4501I. doi:10.1088/1538-3873/aa5800. S2CID   119077156.
  19. ↑ Observatory, Green Bank (2019-10-23). "Breakthrough Listen Announces New Collaboration". Green Bank Observatory. Retrieved 2020-01-10.
  20. ↑ "Breakthrough Listen Releases its one-of-Everything "Exotica" Catalog". Universe Today. 5 July 2020. Retrieved 13 May 2022.
  21. 1 2 "BREAKTHROUGH LISTEN RELEASES LIST OF "EXOTICA" – ONE OF ALMOST EVERY KIND OF OBSERVABLE OBJECT OR PHENOMENON IN THE UNIVERSE". breakthroughinitiatives.org. Retrieved 13 May 2022.
  22. ↑ Lacki, Brian C.; Brzycki, Bryan; Croft, Steve; Czech, Daniel; DeBoer, David; DeMarines, Julia; Gajjar, Vishal; Isaacson, Howard; Lebofsky, Matt; MacMahon, David H. E.; Price, Danny C.; Sheikh, Sofia Z.; Siemion, Andrew P. V.; Drew, Jamie; Worden, S. Pete (1 December 2021). "One of Everything: The Breakthrough Listen Exotica Catalog". The Astrophysical Journal Supplement Series. 257 (2): 42. arXiv: 2006.11304 . Bibcode:2021ApJS..257...42L. doi: 10.3847/1538-4365/ac168a . S2CID   219966544.
  23. ↑ "One Of Everything: The Breakthrough Listen Exotica Catalog - Astrobiology". astrobiology.com. 23 June 2020. Retrieved 13 May 2022.
  24. 1 2 3 4 David H.E. MacMahon; Danny C. Price; Matthew Lebofsky; Andrew P. V. Siemion; Steve Croft; et al. (2018). "The Breakthrough Listen Search for Intelligent Life: A Wideband Data Recorder System for the Robert C. Byrd Green Bank Telescope". Publications of the Astronomical Society of the Pacific. 130 (986): 044502. arXiv: 1707.06024 . Bibcode:2018PASP..130d4502M. doi:10.1088/1538-3873/aa80d2. S2CID   59378232.
  25. ↑ Yunfan Gerry Zhang; Ki Hyun Won; Seung Woo Son; Andrew Siemion; Steve Croft (2019). "Self-Supervised Anomaly Detection for Narrowband SETI". arXiv: 1901.04636 [astro-ph.IM].
  26. 1 2 "Open Data". Breakthrough Initiatives. Archived from the original on 2016-04-16. Retrieved 2016-04-14.
  27. ↑ Toor, Amar (2015-07-20). "Yuri Milner will spend $100 million to look for aliens". The Verge . Retrieved 24 July 2015.
  28. 1 2 ""Breakthrough Listen": Giant Leap for SETI". Sky & Telescope. 2015-07-22. Retrieved 2016-04-14.
  29. ↑ CSIRO. "CSIRO and Internet investor Yuri Milner strike deal for ET search". csiro.au. Retrieved 2016-04-14.
  30. ↑ Overbye, Dennis (2015-07-20). "Stephen Hawking Joins Russian Entrepreneur's Search for Alien Life". The New York Times. ISSN   0362-4331 . Retrieved 2016-04-14.
  31. ↑ "Yuri Milner and Stephen Hawking Announce $100 Million Breakthrough Initiative to Dramatically Accelerate Search for Intelligent Life in the Universe". Breakthrough Initiatives. July 20, 2015. Retrieved 2015-07-24.
  32. 1 2 J. Emilio Enriquez; Andrew Siemion; Danny C. Price; David Macmahon; Matt Lebofsky; et al. (April 21, 2017). "The Breakthrough Listen Search for Advanced Life: 1.1–1.9Ghz Observations of 692 Nearby Stars" (PDF) (Draft) – via berkeley.edu.
  33. ↑ "Breakthrough Listen: L-band 2017". seti.berkeley.edu. Retrieved 2021-03-09.
  34. ↑ "Alien-hunting Breakthrough Listen project tracks strange series of 15 radio bursts". GeekWire. 2017-08-30. Retrieved 2017-09-01.
  35. ↑ Sample, Ian (December 11, 2017). "Astronomers to check interstellar body for signs of alien technology". The Guardian. Retrieved 2017-12-12. Green Bank telescope in West Virginia will listen for radio signals from 'Oumuamua, an object from another solar system ... "Most likely it is of natural origin, but because it is so peculiar, we would like to check if it has any sign of artificial origin, such as radio emissions," said Avi Loeb, professor of astronomy at Harvard University and an adviser to the Breakthrough Listen project. "If we do detect a signal that appears artificial in origin, we'll know immediately." ... While many astronomers believe the object is an interstellar asteroid, its elongated shape is unlike anything seen in the asteroid belt in our own solar system. Early observations of 'Oumuamua show that it is about 400m long but only one tenth as wide. "It's curious that the first object we see from outside the solar system looks like that," said Loeb.
  36. ↑ J. E. Enriquez; A. Siemion; T. J. W. Lazio; M. Lebofsky; D. H. E. MacMahon; et al. (2018). "Breakthrough Listen Observations of 1I/′Oumuamua with the GBT". Research Notes of the American Astronomical Society. 2 (1): 9. arXiv: 1801.02814 . Bibcode:2018RNAAS...2....9E. doi: 10.3847/2515-5172/aaa6c9 . S2CID   119435272.
  37. ↑ David Lipman; Howard Isaacson; Andrew P. V. Siemion; Matt Lebofsky; Danny C. Price; et al. (2018). "The Breakthrough Listen Search for Intelligent Life: Searching Boyajian's Star for Laser Line Emission". Publications of the Astronomical Society of the Pacific. 131 (997): 034202. arXiv: 1812.10161 . doi:10.1088/1538-3873/aafe86. S2CID   119476899.
  38. ↑ Sheikh, Sofia Z.; Siemion, Andrew; Emilio Enriquez, J.; Price, Danny C.; Isaacson, Howard; Lebofsky, Matt; Gajjar, Vishal; Kalas, Paul (2020). "The Breakthrough Listen Search for Intelligent Life: A 3.95-8.00 GHZ Search for Radio Technosignatures in the Restricted Earth Transit Zone". The Astronomical Journal. 160 (1): 29. arXiv: 2002.06162 . Bibcode:2020AJ....160...29S. doi: 10.3847/1538-3881/ab9361 . S2CID   211126496.
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  40. ↑ O'Callaghan, Jonathan; Billings, Lee. "Alien Hunters Discover Mysterious Signal from Proxima Centauri". Scientific American. Retrieved 19 December 2020.
  41. ↑ "Scientists looking for aliens investigate radio beam 'from nearby star'". The Guardian. 2020-12-18. Retrieved 2020-12-18.
  42. ↑ "1st Coordinated Green Bank Telescope/Allen Telescope Array Observes Possible Source of the WOW! Signal".
  43. ↑ Elizabeth Howell (2022-11-07). "No signs of alien life found near source of famous 'Wow!' signal". Space.com. Retrieved 2022-11-13.
  44. ↑ Perez, Karen I. (2022). "Breakthrough Listen Search for the WOW! Signal". AAS. 6 (9): 197. Bibcode:2022RNAAS...6..197P. doi: 10.3847/2515-5172/ac9408 . S2CID   252540293.
  45. ↑ "Breakthrough Listen Search for the WOW! Signal". seti.berkeley.edu. Retrieved 2022-11-13.
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