Search For Extraterrestrial Intelligence Research Research Articles

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.

Multibeam Blind Search of Targeted SETI Observations toward 33 Exoplanet Systems with FAST

The search for extraterrestrial intelligence (SETI) is to search for technosignatures associated with extraterrestrial life, such as engineered radio signals. In this paper, we apply the multibeam coincidence matching (MBCM) strategy, and propose a new search mode based on the MBCM which we call the MBCM blind search mode. In our recent targeted SETI research, 33 exoplanet systems are observed by the Five-hundred-meter Aperture Spherical radio Telescope (FAST). With this blind search mode, we search for narrowband drifting signals across 1.05–1.45 GHz in two orthogonal linear polarization directions separately. There are two special signals, one of which can only be detected by the blind search mode while the other can be found by both blind and targeted search modes. This result reveals huge advantages of the new blind search mode. However, we eliminate the possibility of the special signals being ETI signals based on much evidence, such as the polarization, drift, frequency, and beam coverage characteristics. Our observations achieve an unprecedented sensitivity and our work provides a deeper understanding to the polarization analysis of extraterrestrial signals.

A deep-learning search for technosignatures from 820 nearby stars

The goal of the Search for Extraterrestrial Intelligence (SETI) is to quantify the prevalence of technological life beyond Earth via their "technosignatures". One theorized technosignature is narrowband Doppler drifting radio signals. The principal challenge in conducting SETI in the radio domain is developing a generalized technique to reject human radio frequency interference (RFI). Here, we present the most comprehensive deep-learning based technosignature search to date, returning 8 promising ETI signals of interest for re-observation as part of the Breakthrough Listen initiative. The search comprises 820 unique targets observed with the Robert C. Byrd Green Bank Telescope, totaling over 480, hr of on-sky data. We implement a novel beta-Convolutional Variational Autoencoder to identify technosignature candidates in a semi-unsupervised manner while keeping the false positive rate manageably low. This new approach presents itself as a leading solution in accelerating SETI and other transient research into the age of data-driven astronomy.

Progress of radio search for extraterrestrial intelligence technosignatures

<p indent="0mm">Based on the Copernican principle, Drake’s formula and the discovery of a large number of exoplanets, most scientists believe that there must be life outside the Earth, especially advanced intelligent life (or civilization). Because of the advantages of radio technology, it has become one of the best means to search for extraterrestrial intelligence (SETI). China’s “eye in the sky”, Five-hundred-meter Aperture Spherical radio Telescope (FAST), is the largest single-aperture radio telescope in the world, and SETI is one of its five scientific goals. Its extremely high sensitivity in low frequency radio L-band is of great significance to SETI. Based on the backend equipment of FAST for SETI observation and observing time for FAST, we carry out SETI backend commensal survey observations and exoplanet targeted observations. We find two groups of candidates that demonstrate this RFI mitigation and candidate selection, and validate our SETI instrumentation techniques as well as our data processing pipeline. Cooperating with SETI@home and Breakthrough Listen Team at Berkeley, we develop multibeam coincidence matching (MBCM) strategy and polarization and frequency drift criteria that make the ETI signal identification process more scientific and complete, and conduct observation and data processing to screen ETI candidate targets. We also find a signal at <sc>1140.604 MHz</sc> detected from the observation toward Kepler-438 originally piqued our interest that is roughly consistent with assumed ETI technosignatures. However, its polarization characteristics are able to eliminate the possibility of an extraterrestrial origin. Our observations achieve an unprecedented sensitivity. In addition, we also study the drift rate that is contributed by the rotations and orbits of Earth and the exoplanet in the celestial mechanics perspective, and obtain the expected pseudosinusoidal drifting result with both long-term observations and shorter orbital periods of exoplanets. The characteristics of pseudosinusoidal curves can be applied to long-term SETI reobservations in the future research as another new criterion for extraterrestrial signals. This paper mainly introduces the history of SETI observation in the world, especially the status quo and latest progress of SETI research conducted by FAST, and its future prospects.

An Introduction to Settler Science and the Ethics of Contact

Providing the history and significance of the varied collection of articles in this American Indian Culture and Research Journal special issue, coeditors David Shorter and Kim TallBear describe involvement in an Indigenous studies working group formed in conjunction with the Making Contact 2018 workshop hosted by the Berkeley SETI (Search for Extraterrestrial Intelligence) Research Center. As a whole, “Settler Science, Alien Contact, and Searches for Intelligence” takes a critical eye to frontiers, space exploration, the history of science, and the colonial politics of surveillance technologies.

Indigenous Studies Working Group Statement

In 2018, the authors were invited to share their perspectives as Indigenous studies scholars to the work of Breakthrough Listen, an organization affiliated with both the Berkeley SETI Research Center (BSRC) and the Search for Extraterrestrial Intelligence (SETI). This collectively authored statement highlights some of the ethical concerns these authors perceived regarding the history colonialism and the expectations to find “advanced” or “intelligent” extraterrestrial life. A prologue contextualizes the short working group statement and we then provide the unedited original statement in its entirety.

Choosing a Maximum Drift Rate in a SETI Search: Astrophysical Considerations

Abstract A radio transmitter that is accelerating with a non-zero radial component with respect to a receiver will produce a signal that appears to change its frequency over time. This effect, commonly produced in astrophysical situations where orbital and rotational motions are ubiquitous, is called a drift rate. In radio SETI (Search for Extraterrestrial Intelligence) research, it is unknown a priori which frequency a signal is being sent at, or even if there will be any drift rate at all besides motions within the solar system. Therefore drift rates across the potential range need to be individually searched and a maximum drift rate needs to be chosen. The middle of this range is zero, indicating no acceleration, but the absolute value for the limits remains unconstrained. A balance must be struck between computational time and the possibility of excluding a signal from an ETI. In this work, we examine physical considerations that constrain a maximum drift rate and highlight the importance of this problem in any narrowband SETI search. We determine that a normalized drift rate of 200 nHz (e.g., 200 Hz s−1 at 1 GHz) is a generous, physically motivated guideline for the maximum drift rate that should be applied to future narrowband SETI projects if computational capabilities permit.

Is Anybody Anywhere?

The article discusses the ongoing work of the Center for SETI (Search for Extraterrestrial Intelligence Research) based in Mountain View, California. It particularly focuses on senior astronomer Seth Shostak, who waged in 2003 that humankind will find extraterrestrial life in 24 years. The article also discusses an effort called Breakthrough Listen to survey the million closest stars. The article also discusses the possibility of sending messages inviting contact with intelligent aliens.

#FoundThem–21st Century pre-search and post-detection seti protocols for social and digital media

The transmission of news stories in global culture has changed fundamentally in the last three decades. The general public are alerted to breaking stories on increasingly rapid timescales, and the discussion/distortion of facts by writers, bloggers, commenters and Internet users can also be extremely fast. The narrative of a news item no longer belongs to a small cadre of conventional media outlets, but is instead synthesised to some level by the public as they select where and how they consume news.The IAA Search for Extraterrestrial Intelligence (SETI) post-detection protocols, initially drafted in 1989 and updated in 2010, were written to guide SETI scientists in the event of detecting evidence of extraterrestrial intelligence, but do not give guidance as to how scientists should prepare to navigate this media maelstrom. The protocols assume communication channels between scientists and the public still resemble those of 1989, which were specifically one-way with a narrative controlled by a select few media outlets.Modern SETI researchers must consider this modern paradigm for consumption of news by the public, using social media and other non-traditional outlets, when planning and executing searches for extraterrestrial intelligence. We propose additions to the post detection protocols as they pertain to the use of the Internet and social media, as well as pre-search protocols. It is our belief that such protocols are necessary if there is to be a well-informed, sane global conversation amongst the world’s citizens following the discovery of intelligent life beyond the Earth.

SETI reloaded: Next generation radio telescopes, transients and cognitive computing

The Search for Extra-terrestrial Intelligence (SETI) using radio telescopes is an area of research that is now more than 50 years old. Thus far, both targeted and wide-area surveys have yet to detect artificial signals from intelligent civilisations. In this paper, I argue that the incidence of co-existing intelligent and communicating civilisations is probably small in the Milky Way. While this makes successful SETI searches a very difficult pursuit indeed, the huge impact of even a single detection requires us to continue the search. A substantial increase in the overall performance of radio telescopes (and in particular future wide-field instruments such as the Square Kilometre Array – SKA), provide renewed optimism in the field. Evidence for this is already to be seen in the success of SETI researchers in acquiring observations on some of the world׳s most sensitive radio telescope facilities via open, peer-reviewed processes. The increasing interest in the dynamic radio sky, and our ability to detect new and rapid transient phenomena such as Fast Radio Bursts (FRB) is also greatly encouraging. While the nature of FRBs is not yet fully understood, I argue they are unlikely to be the signature of distant extra-terrestrial civilisations. As astronomers face a data avalanche on all sides, advances made in related areas such as advanced Big Data analytics, and cognitive computing are crucial to enable serendipitous discoveries to be made. In any case, as the era of the SKA fast approaches, the prospects of a SETI detection have never been better.

Examining the Definition of Astrosociology

A void has existed within the social sciences for over fifty years since the launch of the first Sputnik satellite in October 1957. This void delineates the boundaries of a missing field, a discipline capable of focusing on the relationship between social life and outer space. It is true that social scientists have pursued space issues over the last thirty years or so. As individuals, they have participated in the areas of search for extraterrestrial intelligence research, astrobiology, space policy, and space history. The strength of astrosociology, however, lies in its formalization of this type of approach into an identifiable field of study, which allows for a more organized and inclusive opportunity for participation. As a starting point, one may express the relationship between social life and outer space as astrosociology. One can define astrosociology as the study of social, cultural, and behavioral patterns related to outer space. The purpose of this article is to provide a general framework for more precise language concerning the definition, scope, character, and future development of astrosociology, while simultaneously attempting to elicit a broader discussion of astrosociology's association to other disciplines. It suggests how the various fields and disciplines associated with astrosociology as a multidisciplinary field can work together to build a missing body of knowledge from their related literatures and contemporary research.

Numerical testing of the Rare Earth Hypothesis using Monte Carlo realization techniques

AbstractThe Search for Extraterrestrial Intelligence (SETI) has thus far failed to provide a convincing detection of intelligent life. In the wake of this null signal, many ‘contact-pessimistic’ hypotheses have been formulated, the most famous of which is the Rare Earth Hypothesis. It postulates that although terrestrial planets may be common, the exact environmental conditions that Earth enjoys are rare, perhaps unique. As a result, simple microbial life may be common, but complex metazoans (and, hence, intelligence) will be rare. In this paper we use Monte Carlo realization techniques to investigate the Rare Earth Hypothesis, in particular the environmental criteria considered imperative to the existence of intelligence on Earth. By comparing with a less restrictive, more optimistic hypothesis, the data indicate that if the Rare Earth hypothesis is correct, intelligent civilization will indeed be relatively rare. Studying the separations of pairs of civilizations shows that most intelligent civilization pairs (ICPs) are unconnected: that is, they will not be able to exchange signals at lightspeed in the limited time that both are extant. However, the few ICPs that are connected are strongly connected, being able to participate in numerous exchanges of signals. This may provide encouragement for SETI researchers: although the Rare Earth Hypothesis is in general a contact-pessimistic hypothesis, it may be a ‘soft’ or ‘exclusive’ hypothesis, i.e. it may contain facets that are latently contact-optimistic.

Responsibility, capability, and Active SETI: Policy, law, ethics, and communication with extraterrestrial intelligence

With recently growing interest in the Active Search for Extraterrestrial Intelligence (SETI), in which humankind would send intentional signals to extraterrestrial civilizations, there have been increased concerns about appropriate policy, as well as the role of space law and ethics in guiding such activities. Implicit in these discussions are notions of responsibility and capability that affect judgments about whether humans or other civilizations should initiate transmissions. Existing protocols that guide SETI research address transmissions from Earth, but there is debate over whether these guidelines should inform de novo transmissions as well. Relevant responsibilities to address include (1) looking out for the interests of humankind as a whole, (2) being truthful in interstellar messages, and (3) benefiting extraterrestrial civilizations. Our capabilities as a species and a civilization affect how well we can fulfill responsibilities, as seen when we consider whether we will be able to reach consensus about message contents (and whether that would be desirable), and whether we have the capacity to decode messages from beings that rely on different sensory modalities. The interplay of these responsibilities and capabilities suggests that humankind should place increased emphasis on Active SETI.