Search For Extraterrestrial Intelligence Research Articles

The Breakthrough Listen Search for Intelligent Life: Galactic Center Search for Scintillated Technosignatures

The search for extraterrestrial intelligence at radio frequencies has focused on spatial filtering as a primary discriminant from terrestrial interference. Individual search campaigns further choose targets or frequencies based on criteria that theoretically maximize the likelihood of detection, serving as high-level filters for interesting targets. Most filters for technosignatures do not rely on intrinsic signal properties, as the radio-frequency interference (RFI) environment is difficult to characterize. In B. Brzycki et al. (2023), we proposed that the effects of interstellar medium (ISM) scintillation on narrowband technosignatures may be detectable under certain conditions. In this work, we perform a dedicated survey for scintillated technosignatures toward the Galactic center and Galactic plane at the C band (3.95–8.0 GHz) using the Robert C. Byrd Green Bank Telescope (GBT) as part of the Breakthrough Listen program. We conduct a Doppler drift search and directional filter to identify potential candidates and analyze results for evidence of scintillation. We characterize the C-band RFI environment at the GBT across multiple observing sessions spread over months and detect RFI signals with confounding scintillation-like intensity modulation. We do not find evidence of putative narrowband transmitters with drift rates between ±10 Hz s−1 toward the Galactic center, ISM-scintillated or otherwise, above an equivalent isotropic radiated power of 1.9 × 1017 W up to 8.5 kpc.

Phenomenal consciousness is alien to us: SETI and the fermi paradox seen through the prism of illusionism and attention schema theory

Illusionism is an eliminativist position about qualia stating that phenomenal consciousness is nothing more than an introspective illusion. The attention schema theory (AST) relates this philosophical stance to a large body of experimental data and states that phenomenal consciousness arises from an internal model of attention control. In this paper, I intend to show that AST and illusionism have significant implications both in the search for extra-terrestrial intelligence and in the explanation of Fermi paradox.Firstly, on the basis of findings concerning the evolutionary history of phenomenal consciousness on Earth, I argue that extraterrestrial biological life is likely to experience phenomenality. In the second part, I set AST in the context of a post-biological universe, where artificial intelligence (AI) is the dominant form of intelligence. I argue that phenomenal consciousness is probably present in these entities, and that they could even be super-conscious. Finally, I show that because phenomenality grounds value, illusionism has profound revisionary consequences in the field of ethics. This reconsideration of the justifiability of our values paves the way to AI misalignment and may be the source of neocatastrophic scenarios that explain to Fermi paradox.

Searching for extraterrestrial intelligence across a century

Abstract This short paper explores the century-long journey of searching for extraterrestrial intelligence (SETI) with a focus on the radiowave spectrum. Beginning with early experiments by David Todd and Charles Jenkins, who attempted interplanetary communication using radio technology, it traces the historical development of SETI. The paper discusses significant milestones, such as Project OZMA in 1961 and the transition to modern searches, particularly the Breakthrough Listen project, which represents the most comprehensive effort in SETI history. The vastness of the Universe, the potential for life in various planetary systems and the challenges of differentiating between basic life and intelligent life are highlighted. The discussion includes the concept of technosignatures—signals indicative of advanced technology—and the advancements in telescope technology like the Square Kilometre Array Observatory (SKAO) that enhance SETI capabilities. Recent developments are also addressed, such as an intriguing signal detected in 2020 and the future of SETI is envisioned, including the possibility of building a radio telescope on the far side of the Moon to escape interference from human technosignatures as humans continue to expand into space.

Searching for extraterrestrial intelligence across a century

Abstract SETI, the Search for Extraterrestrial Intelligence, is an old idea but a new science. Both inspirational and controversial, the scientific search for non-human artificial signals or communications, known as technosignatures, was pioneered by a few visionary scientists and through amazing technological advances of recent years is experiencing a renaissance that may soon answer one of the greatest scientific questions of this or any age: Are we alone? This paper describes the origins of SETI science, its rocky road to acceptance and some of the bold new ideas and explorations that are pushing the limits of our understanding of the nature of life and intelligence in the Universe.

Searching for extraterrestrial intelligence across a century

Abstract Exobiology is a burgeoning research field. There is a realistic prospect that in a decade or two we will have the capability to detect biosignatures – non-equilibrium atmospheric chemistry, vegetation etc. – for the nearest exoplanets. But of course what is most interesting of all would be some techno-signatures, indicating not just ‘life’, but intelligent life. This paper offers some introductory comments on this topic.

Project Hephaistos – II. Dyson sphere candidates from Gaia DR3, 2MASS, and WISE

ABSTRACT The search for extraterrestrial intelligence is currently being pursued using multiple techniques and in different wavelength bands. Dyson spheres, megastructures that could be constructed by advanced civilizations to harness the radiation energy of their host stars, represent a potential technosignature, that in principle may be hiding in public data already collected as part of large astronomical surveys. In this study, we present a comprehensive search for partial Dyson spheres by analysing optical and infrared observations from Gaia, 2MASS, and WISE. We develop a pipeline that employs multiple filters to identify potential candidates and reject interlopers in a sample of five million objects, which incorporates a convolutional neural network to help identify confusion in WISE data. Finally, the pipeline identifies seven candidates deserving of further analysis. All of these objects are M-dwarfs, for which astrophysical phenomena cannot easily account for the observed infrared excess emission.

Universidad del Atlántico Medio

The search for extraterrestrial intelligence on exoplanets is a rich field of conceptual exploration. Author introduces two definitions that could help to narrow down the possibilities that an extraterrestrial civilization may or may not have initiated exploration of its own star system and beyond. It is concluded that in some cases certain extraterrestrial civilizations may not be able to leave their home worlds before their biological extinction, purely because of physical limitations. Keywords: SETI, ETI, Exoplanets, Alien Civilizations, Alien Exploration

Research repertoires and boundary work in the search for extra-terrestrial intelligence (SETI)

ABSTRACT The idea of scouting the sky in search of extra-terrestrial signals (SETI) was first proposed in the late 1950s; soon afterwards, its scope was formalised in the so-called Drake Equation, a probabilistic argument to gauge the number of ‘civilisations’ capable of radio communication on the basis of astronomical, biological and cultural factors. Since then, radio telescopes around the world have been searching for an artificial signal from elsewhere in the universe, a sign of extraterrestrial communication. How have SETI practitioners claimed scientific legitimacy and epistemic authority over the search for extra-terrestrial life, a matter often regarded to be at the very periphery of science? And how have they succeeded (or failed) in maintaining them over time? The historical trajectory of SETI offers the opportunity to investigate how, over time, an interdisciplinary community coalesced around a research repertoire and navigated ebbs and flows of interest by rearticulating the methods and scope of their research. The ‘probability repertoire’ around which the SETI community coalesced is an evolving entity, entailing significant boundary work. As with every successful repertoire, it is a flexible but always entailing a recognisable alignment of material, social and epistemic components instrumental for a research community in gaining recognition and negotiating its epistemic positioning within the always shifting boundaries of science.

Deciding Technosignature Search Strategies: Multi-Criteria Fuzzy Logic to Find Extraterrestrial Intelligence

This study presents the implementation of Multi-Criteria Decision-Making (MCDM) methodologies, particularly the fuzzy technique for order of preference by similarity to ideal solution (TOPSIS), in prioritizing technosignatures (TSs) for the search for extraterrestrial intelligence (SETI). By incorporating expert opinions and weighted criteria based on the established Axes of Merit, our analysis offers insights into the relative importance of various TSs. Notably, radio and optical communications are emphasized, in contrast to dark side illumination and starshades in transit. We introduce a new axis, Scale Sensitivity, designed to assess the variability of TS metrics. A sensitivity analysis confirms the robustness of our approach. Our findings, especially the highlighted significance of artifacts orbiting Earth, the Moon, or the Sun, indicate a need to broaden evaluative criteria within SETI research. This suggests an enhancement of the Axes of Merit, with a focus on addressing the plausibility of TSs. As the quest to resolve the profound question of our solitude in the cosmos continues, SETI efforts would benefit from exploring innovative prioritization methodologies that effectively quantify TS search strategies.

Shuffled frog Leaping algorithm based circular patterns loaded ring shaped fractal antenna for multistandard wireless applications

This paper describes the design and experimental behavior of a 2nd iterated modified Square Ring Shaped Fractal Antenna (SRSFA). The radiator geometry consists of three symmetrical square-shaped rings loaded with circular patterns at the corners. The designed fractal patch is placed on a slot loaded ground structure. The electrical dimensions possessed by the realized structure are 0.15λ0 x 0.15λ0 x 0.080 λ0, and the whole antenna is implemented using FR4 substrate. In this design, transmission line width ‘WF’ and position ‘FP’ are optimized using Shuffled Frog Leaping Algorithm (SFLA) and Artificial Bee Colony (ABC) strategies. It has been examined that the optimized values of ‘WF’ and ‘FP’ using SFLA and ABC are 2.6 and 12.4 mm, and 3.2 and 15.9 mm, respectively. Results reveal that SFLA offers better solution quality and convergence speed than ABC. Further, experimental analysis has been demonstrated to effectively illustrate the recommended fractal approach. The equivalent circuit of the designed structure is implemented successfully. The conducted measurements show that for VSWR ≤ 2, the fabricated structure produces six resonance points with adorable S11 values. The resonances appear at 1.53 GHz (1.35–1.67 GHz), 4.30 GHz (4.20–4.40 GHz), 7.58 GHz (7.43–7.70 GHz), 11.35 GHz (10.37–11.58 GHz), 14.03 GHz (13.85–14.35 GHz), and 15.93 GHz (15.43–16.25 GHz). The examined −10 dB impedance bandwidth at the respective resonance points is 20.9 %, 4.6 %, 3.5 %, 11.3 %, 2.9 %, and 5.23 %. Healthy concordance is noticed among the experimental measurements and electromagnetic simulations. The demonstrated radiation patterns are arbitrary bidirectional/omnidirectional at the respective resonances with good stability. Additionally, the offered gain is within the range of 4.91–7.00 dB. Hence, by utilizing the above-mentioned approaches, miniaturization of 65 % has been achieved. Practical outcomes suggest that the introduced prototype exhibiting multiband behavior, can be effectively applied in Radio location, Radio astronomy, Long-range tracking, Weather location Broadcasting, Search for extra-terrestrial intelligence, Radar altimeters, High resolution mapping, Aeronavigation, and Miscellaneous Radars.

Stephen Hawking's Warning on Contacting Aliens: A Physics Perspective on the Intelligence Trap.

The search for extraterrestrial intelligence is a fascinating and important endeavor, but it raises significant ethical and safety concerns. In the search for extraterrestrial intelligence, scientists use knowledge of physics to identify potential communication methods and signals that may be used by extraterrestrial civilizations. One of the most notable scientists to highlight these concerns was the late physicist Stephen Hawking, who cautioned that actively attempting to communicate with extraterrestrial civilizations could harm humanity. While it is true that we cannot predict the intentions of any potential extraterrestrial civilizations, some scientists argue that the potential advantages of seeking contact outweigh the potential risks. Deciding to initiate contact with extraterrestrial civilizations is a complex issue that requires balancing scientific curiosity with concerns for our own safety. The "Intelligence Trap" is a concept in psychology that suggests that highly intelligent people are more susceptible to cognitive biases and flawed thinking than less intelligent people. It can be argued that Hawking's warnings may be an example of the so-called intelligence trap, as some evidence from the field of physics suggests. Nonetheless, Hawking emphasized that it is crucial for scientists and policymakers to carefully weigh the potential risks and benefits of such efforts and proceed with caution.

Identifying optimal decision-making strategies and determining effective messaging to maximize the expected outcomes of potential human–extraterrestrial encounters

Abstract The question of whether extraterrestrials exist has driven both the search for extraterrestrial intelligence (SETI) and some attempts of messaging to extraterrestrial intelligence (METI). Nevertheless, no data-driven or theory-based behavioural policy has been suggested. Here we simulate a comprehensive set of human–extraterrestrial strategic interactions, modelled as two-by-two game-theoretic matrices. We examine a sample of possible outcomes by relying on the theory of subjective expected relative similarity (SERS), which takes into account both the expected payoffs and the extent of strategic similarity – the prospects of the opponent making identical choices. Simulation results suggest: focusing messaging efforts on signalling of complete strategic similarity, monitoring potential alien communications for similarity-indicating signals, and using risk-averse decision rules for policy planning and decision-making. The discussion puts forward three guidelines for METI initiatives and addresses the relevance of the findings to human conflict management.

Psychological aspects in unidentified anomalous phenomena (UAP) witnesses

Abstract In this study, we surveyed a total of 245 people about unidentified anomalous phenomena (UAP), 93 who directly witnessed UAP. Paying special attention to the psychological impact of UAP, our study survey covered different aspects, including opinions on official UAP releases, the scientific approach to the phenomena and the search for extra-terrestrial intelligence. This study found that UAP had a clear psychological impact on witnesses, with a transformative effect, and a benign form of a non-pathological obsessive-like interest in the topic we defined as the UAP deep psychological engagement triad. This deep psychological engagement triad is characterized by UAP topic being present in a witness's mind daily, with a self-recognized interest and appreciation for the topic and a need to talk about UAP topic, not necessarily the event they experienced. UAP appear to have a very specific impact focused on extra-terrestrial aspects and the phenomena itself, which is experienced as a life-changing event by direct witnesses. These psychological aspects are quantitatively and qualitatively objectifiable, and further research is needed in this direction since all research efforts appear currently focused on the physical aspects of these phenomena.

Polarization Criterion in Targeted SETI Observation

In this paper, we propose a novel method for distinguishing extraterrestrial intelligence (ETI) signals from radio frequency interference (RFI) by leveraging polarization features. We exploit the sinusoidal variation of the linearly polarized components of Stokes parameters with the parallactic angle as a characteristic signature of ETI signals, while such linearly polarized components remain relatively stable for terrestrial RFI. Typically, a minimum of 4–8 hr of observation time is required to detect these sinusoidal variations. The polarization approach in the search for extraterrestrial intelligence also enables us to study the radio stellar bursts emitted by M-type stars as ancillary science, which is relevant to assessing the habitability of exoplanets. Compared to the frequency drift method, the polarization method effectively reduces the required observation time for signal identification while improving the signal identification process.

Children of time: the geological recency of intelligence and its implications for SETI

Abstract Of all species on Earth, only one – Homo sapiens – has developed a technological civilization. As a consequence, estimates of the number of similar civilizations beyond Earth often treat the emergence of human-like intelligence or ‘sophonce’ as an evolutionary unicum: a contingent event unlikely to repeat itself even in biospheres harbouring complex brains, tool use, socially transmitted behaviours and high general intelligence. Here, attention is drawn to the unexpected recency and temporal clustering of these evolutionary preconditions to sophonce, which are shown to be confined to the last ≤102 million years. I argue that this pattern can be explained by the exponential biotic diversification dynamics suggested by the fossil record, which translated into a nonlinearly expanding range of cognitive and behavioural outcomes over the course of Earth's history. As a result, the probability of sophonce arising out of a buildup of its enabling preconditions has been escalating throughout the Phanerozoic. The implications for the Silurian hypothesis and the search for extraterrestrial intelligence (SETI) are discussed. I conclude that the transition from animal-grade multicellularity to sophonce is likely not a rate-limiting step in the evolution of extraterrestrial technological intelligences, and that while H. sapiens is probably the first sophont to evolve on Earth, on macroevolutionary grounds it is unlikely to be the last.

A Solution to Continuous RFI in Narrowband Radio SETI with FAST: The MultiBeam Point-source Scanning Strategy

Narrowband radio search for extraterrestrial intelligence (SETI) in the 21st century suffers severely from radio frequency interference (RFI), resulting in a high number of false positives, and it could be the major reason why we have not yet received any messages from space. We thereby propose a novel observation strategy, called MultiBeam Point-source Scanning (MBPS), to revolutionize the way RFI is identified in narrowband radio SETI and provide a prominent solution to the current situation. The MBPS strategy is a simple yet powerful method that sequentially scans over the target star with different beams of a telescope, creating real-time references in the time domain for cross-verification and thus potentially identifying all continuous RFI with a level of certainty never achieved in any previous attempts. By applying the MBPS strategy during the observation of TRAPPIST-1 with the Five-hundred-meter Aperture Spherical radio Telescope, we successfully identified all 6972 received signals as RFI using the solid criteria introduced by the MBPS strategy. Therefore, we present the MBPS strategy as a promising tool that should bring us much closer to the first discovery of a genuine galactic greeting.

The Most Sensitive SETI Observations Toward Barnard's Star with FAST

Search for extraterrestrial intelligence (SETI) has been mainly focused on nearby stars and their planets in recent years. Barnard’s star is the second closest star system to the Sun and the closest star in the Five-hundred-meter Aperture Spherical radio Telescope (FAST) observable sky which makes the minimum Equivalent Isotropic Radiated Power required for a hypothetical radio transmitter from Barnard’s star to be detected by FAST telescope a mere 4.36 × 108 W. In this paper, we present the FAST telescope as the most sensitive instrument for radio SETI observations toward nearby star systems and conduct a series of observations to Barnard’s star (GJ 699). By applying the multibeam coincidence matching strategy on the FAST telescope, we search for narrow-band signals (∼Hz) in the frequency range of 1.05–1.45 GHz, and two orthogonal linear polarization directions are recorded. Despite finding no evidence of radio technosignatures in our series of observations, we have developed predictions regarding the hypothetical extraterrestrial intelligence signal originating from Barnard’s star. These predictions are based on the star’s physical properties and our observation strategy.

Planetary biotechnospheres, biotechnosignatures and the search for extraterrestrial intelligence

AbstractThe concept of planetary intelligence as collective intelligence is used to consider possible evolutionary paths of biotechnospheres that emerge on the intersection of the technosphere with the biosphere and support coupling of the technosphere with the biosphere, thus affecting planetary evolution. In mature biotechnospheres, the intelligence of technologies and the intelligence of life forms, including engineered life forms, could act in concert to perform various tasks (e.g. monitoring planetary biospheres and environments; restoring planetary environments and biodiversity; steading planetary environments; providing support for space missions; terraforming cosmic objects). Space exploration can expand biotechnospheres beyond planets and create cosmic ecosystems encompassing planets and other cosmic objects; biotechnospheres, spacecraft and the environments of near-planetary, interplanetary space or interstellar space. Humankind, other civilizations or their intelligent machines may produce biotechnosignatures (i.e. observables and artefacts of biotechnospheres) in the Solar System and beyond. I propose ten possible biotechnosignatures and strategies for the search for these biotechnosignatures in situ and over interstellar distances. For example, if a non-human advanced civilization existed and built biotechnospheres on Earth in the past, its biotechnospheres could use engineered bacteria and the descendants of that bacteria could currently exist on Earth and have properties pertaining to the functions of the ancient bacteria in the biotechnospheres (such properties are proposed and discussed); intelligent technologies created by the ancient civilization could migrate to the Solar System's outer regions (possible scenarios of their migration and their technosignatures and biotechnosignatures are discussed); these two scenarios are described as the Cosmic Descendants hypothesis. Interstellar asteroids, free-floating planets, spacecraft and objects gravitationally bound to flyby stars might carry extraterrestrial biotechnospheres and pass through the Solar System. In connection to the fate of post-main-sequence stars and their Oort clouds, the probability for interstellar asteroids to carry biotechnospheres or to be interstellar spacecraft is estimated as very low.

A Search for Extraterrestrial Technosignatures in Archival FAST Survey Data Using a New Procedure

The search for extraterrestrial intelligence (SETI) commensal surveys aim to scan the sky to find possible technosignatures from an extraterrestrial intelligence (ETI). The mitigation of radio frequency interference (RFI) is an important step, especially for the most sensitive Five-hundred-meter Aperture Spherical radio Telescope (FAST), which can detect more weak RFI. In this paper, we propose several new techniques for RFI mitigation and use our procedure to search for ETI signals from the archival data of FAST’s first SETI commensal survey. We detect the persistent narrowband RFI by setting a threshold of the signals’ sky separation and detect the drifting RFI (and potentially other types of RFI) using the Hough transform. We also use the clustering algorithms to remove more RFI and select candidates. The results of our procedure are compared to the earlier work on the same FAST data. We find that our methods, though relatively simpler in computation, remove more RFI (99.9912% compared to 99.9063% in the earlier work) but preserve the simulated ETI signals, except for those (5.1%) severely affected by the RFI. We also report more interesting candidate signals, about a dozen of which are new candidates that were not previously reported. In addition, we find that the proposed Hough transform method, with suitable parameters, also has the potential to remove the broadband RFI. We conclude that our methods can effectively remove the vast majority of the RFI while preserving and finding the candidate signals that we are interested in.

A sign in space: An interdisciplinary exploration of the potential reception of an extraterrestrial signal

A Sign in Space is an interdisciplinary project by media artist Daniela de Paulis, in collaboration with the Green Bank Observatory, the National Institute for Astrophysics, the SETI Institute and the European Space Agency.The project consists in transmitting a simulated extraterrestrial message as part of a live performance, using an ESA spacecraft as celestial source. The objective of the project is to involve the worldwide search for extraterrestrial intelligence (SETI) community, professionals from different fields and the broader public in the reception, decoding and interpretation of the message. This process will require global cooperation, bridging a conversation around the topics of SETI, space research and society, across multiple cultures and fields of expertise.