TL;DR:
- Breakthrough Listen project scans the skies using advanced radio telescopes to search for evidence of technological activity from extraterrestrial civilizations.
- VERITAS Collaboration joins forces with Breakthrough Listen, utilizing gamma-ray telescopes, to expand the search for optical technosignatures.
- The recent publication shares the results of the first year-long investigation into optical technosignatures, showcasing the potential for future searches.
- The study explores various potential extraterrestrial technological signatures, broadening the search beyond radio transmissions.
- VERITAS array’s cutting-edge capabilities allow for the detection of nanosecond optical pulses across interstellar distances.
- The collaboration analyzed a comprehensive target catalog and examined archival data, but did not find evidence of nanosecond optical pulses.
- The study provides a crucial proof-of-concept, guiding future searches and narrowing down potential stars hosting transmitting civilizations.
- Existing and future gamma-ray observatories, such as VERITAS and PANOSETI, can play a significant role in the search for optical technosignatures.
Main AI News:
In a bid to unravel the mysteries of the universe, Breakthrough Initiatives, spearheaded by Russian-Israeli billionaire Yuri Milner, launched the ambitious Breakthrough Listen project in 2015. This grand endeavor, the largest Search for Extraterrestrial Intelligence (SETI) project to date, harnesses the power of cutting-edge radio telescopes and advanced analytics to hunt for potential traces of technological activity, also known as “technosignatures.” Over the course of a decade, this initiative aims to survey a staggering one million stars in close proximity to Earth, the core of our galaxy, the entire galactic plane, and the 100 galaxies closest to the Milky Way.
To bolster their quest for answers, Breakthrough Listen joined forces with the esteemed Very Energetic Radiation Imaging Telescope Array System (VERITAS) Collaboration in 2018. VERITAS operates a network of ground-based gamma-ray telescopes situated at the Fred Lawrence Whipple Observatory (FLWO) atop Arizona’s Mt. Hopkins. Recently, the collaboration published a noteworthy paper showcasing the results of their first year-long investigation into “optical technosignatures” from 2019 to 2020. These findings offer a crucial proof of concept, illustrating how future searches for extraterrestrial civilizations can incorporate optical pulses into their technosignature catalog.
The VERITAS Collaboration represents a multinational collaboration comprising researchers from esteemed institutions such as FLWO, the Harvard-Smithsonian Center for Astrophysics (CfA), the Arthur B. McDonald Canadian Astroparticle Physics Research Institute, the Deutsches Elektronen-Synchrotron (DESY) research center, the NASA Goddard Space Flight Center, as well as numerous universities and research institutes. The publication titled “A VERITAS/Breakthrough Listen Search for Optical Technosignatures” is slated for release in The Astronomical Journal.
For the past six decades, the search for extraterrestrial intelligence (ETI), beginning with Project Ozma, has predominantly revolved around detecting radio signals. However, in recent years, scientists have broadened their scope to consider a wider array of potential technosignatures. These encompass directed-energy communications, radio and optical leakage from advanced civilizations, infrared emissions from colossal structures, spectral evidence of industrial pollutants in exoplanet atmospheres, and even the presence of spacecraft or debris within our Solar System. The exploration of these and other extraterrestrial technological possibilities was outlined in the NASA Technosignature Workshop Report of 2018.
By incorporating VERITAS, equipped with four 12-meter Cherenkov optical reflectors tailored for gamma-ray astronomy, Breakthrough Listen has expanded its search to encompass optical technosignatures. In particular, they aim to detect nanosecond optical pulses capable of traversing interstellar distances. Gregory Foote, a Ph.D. candidate at the University of Delaware’s Department of Physics and Astronomy and a co-author of the VERITAS paper, elucidated the rationale behind this pursuit in an email exchange with Universe Today: “While radio technosignatures have traditionally been the focus, we cannot ascertain the precise waveband or whether the signal will be pulsed or continuous. Hence, it is prudent to explore diverse avenues. In principle, the technosignature we seek, pulsed lasers, can be readily detected and transmitted across a distance of 1000 light-years using current technology. VERITAS, with its formidable telescopes, empowers us to scour the cosmos for these pulsed lasers.”
Established in 2007, the VERITAS array serves as a complementary asset to NASA’s Fermi Gamma-ray Space Telescope (FRGST) and the Large Area Telescope (LAT) collaboration, of which Fermi is a partner. Boasting a larger collection area and heightened sensitivity to gamma rays, VERITAS’ segmented mirror telescopes, akin to the primary mirror of the upcoming James Webb Space Telescope (JWST), outshine all other telescopes in the very-high-energy (VHE) band. They achieve a maximum sensitivity ranging from 100 giga-electronvolts (GeV) to 10 tera-electronvolts (TeV).
Putting their capabilities to the test, the Collaboration’s team scoured through the Breakthrough Listen target catalog in search of high-energy optical pulses. Foote elaborated on the process, stating, “We began with the 2017 Breakthrough Listen target catalog and excluded unsuitable targets for VERITAS. This narrowed down the list to approximately 506 potential targets, which were subsequently ranked based on their proximity, luminosity, and other favorable criteria—such as the presence of exoplanets. Armed with this ranked list, we could select the highest-priority targets visible during a given month. In total, we observed 136 targets, including a few instances where multiple objects were observed, amounting to a cumulative observation time of 30 hours.“
Additionally, the Collaboration examined VERITAS’ archival data spanning back to 2012 and cross-referenced it with the Breakthrough Listen catalog to identify targets observed during the same period. Due to computational constraints, they focused on analyzing only the first hour of high-quality data from a diverse array of targets. Foote elaborated further, saying, “This led us to 249 observations encompassing 119 distinct fields with 140 non-overlapping targets captured serendipitously. Regrettably, none of these observations provided evidence of the sought-after technosignature.”
Despite the absence of nanosecond optical pulses in their analysis, the study carries significant implications as a proof-of-concept, shaping the future trajectory of technosignature searches. Furthermore, it has aided in establishing constraints on the number of stars potentially harboring transmitting civilizations, effectively refining search parameters and enhancing the probability of future detections. Foote emphasizes that this research could also impact existing gamma-ray observatories and forthcoming ones, including the Panoramic All-sky All-time Near InfraRed and Optical Technosignature Finder (PANOSETI), which plans to conduct coordinated observations with the Veritas Observatory: “An intriguing aspect of this study is that the search for this specific technosignature can be piggybacked onto existing gamma-ray observatories like VERITAS, as well as those yet to be constructed. Conversely, gamma-ray science can be intertwined with observatories built specifically for this technosignature, such as PANOSETI. This marks an unprecedented intersection between fields that, until now, has remained relatively unexplored.“
Conclusion:
The collaboration between Breakthrough Listen and the VERITAS Collaboration marks an important milestone in the search for potential extraterrestrial civilizations. By expanding the investigation to include optical technosignatures, they are broadening the scope and possibilities in the quest for evidence of technological activity beyond radio transmissions. While the study did not find evidence of nanosecond optical pulses, it provides a valuable proof-of-concept and guides future searches, narrowing down the potential stars that may host transmitting civilizations. Furthermore, the research highlights the significance of existing and future gamma-ray observatories, such as VERITAS and upcoming projects like PANOSETI, in advancing the search for optical technosignatures. This collaboration and the exploration of new avenues bring exciting prospects for the market of extraterrestrial research and our understanding of the universe.
