Searching for technosignatures in exoplanetary systems with current and future missions

Haqq-Misra, Jacob; Schwieterman, Edward W.; Socas‐Navarro, H.; Kopparapu, R.; Angerhausen, Daniel; Beatty, Thomas G.; Berdyugina, S. V.; Felton, Ryan; Sharma, Siddhant; Torre, Gabriel G. De la; Apai, Dániel

doi:10.1016/j.actaastro.2022.05.040

Cited by 15 publications

(10 citation statements)

References 172 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this context, determining whether a world has surficial landmasses and/or oceans is feasible, in principle, via spectrophotometric observations (Cowan et al 2009;Fujii et al 2010Fujii et al , 2018Lustig-Yaeger et al 2018;Kuwata et al 2022). Hence, if future technosignature surveys (reviewed in Lingam & Loeb 2021b;Wright 2021;Socas-Navarro et al 2021;Haqq-Misra et al 2022) discover that the majority of signals emanate from ocean worlds (sans LBHs by definition), this trend might assist in confirming hypothesis #1. In contrast, if most technosignatures originate from worlds with LBHs, this result may serve to falsify hypothesis #1 and thereby lend credence to the other outcomes.…”

Section: Discussionmentioning

confidence: 95%

A Bayesian Analysis of Technological Intelligence in Land and Oceans

Lingam

Balbi

Mahajan

2023

ApJ

View full text Add to dashboard Cite

Current research indicates that (sub)surface ocean worlds essentially devoid of subaerial landmasses (e.g., continents) are common in the Milky Way and that these worlds could host habitable conditions, thence raising the possibility that life and technological intelligence (TI) may arise in such aquatic settings. It is known, however, that TI on Earth (i.e., humans) arose on land. Motivated by these considerations, we present a Bayesian framework to assess the prospects for the emergence of TIs in land- and ocean-based habitats (LBHs and OBHs). If all factors are equally conducive for TIs to arise in LBHs and OBHs, we demonstrate that the evolution of TIs in LBHs (which includes humans) might have very low odds of roughly 1 in 103 to 1 in 104, thus outwardly contradicting the Copernican principle. Hence, we elucidate three avenues whereby the Copernican principle can be preserved: (i) the emergence rate of TIs is much lower in OBHs, (ii) the habitability interval for TIs is much shorter in OBHs, and (iii) only a small fraction of worlds with OBHs comprise appropriate conditions for effectuating TIs. We also briefly discuss methods for empirically falsifying our predictions and comment on the feasibility of supporting TIs in aerial environments.

show abstract

Section: Discussionmentioning

confidence: 95%

A Bayesian Analysis of Technological Intelligence in Land and Oceans

Lingam

Balbi

Mahajan

2023

ApJ

View full text Add to dashboard Cite

show abstract

“…It is natural to conceive of atmospheric components (e.g., gases) that are manufactured by means of extraterrestrial technology instead of biology. A few candidates have been proposed in this domain, which are reviewed in Lingam & Loeb (2021, Section 9.5) and Haqq-Misra et al (2022c).…”

Section: Atmospheric Technosignaturesmentioning

confidence: 99%

“…Ever since that time period, the realm of technosignatures-an apposite term coined by Tarter (2007)-has broadened to encompass multiple search strategies and novel signatures of extraterrestrial technology. State-of-the-art reviews of this subject are furnished in Tarter (2001), Bradbury et al (2011), Cabrol (2016), Lingam & Loeb (2019), Lingam & Loeb (2021), Wright (2021), andHaqq-Misra et al (2022c), among other sources. The search for technosignatures is embedded within the larger domain of astrobiology (Tarter 2004;Wright 2018).…”

Section: Introductionmentioning

confidence: 99%

Technosignatures: Frameworks for Their Assessment

Lingam

Haqq-Misra

Wright

et al. 2023

ApJ

Self Cite

View full text Add to dashboard Cite

In view of the promising advancements in technosignature science, the question of what constitutes a robust technosignature is rendered crucial. In this paper, we first delineate a Bayesian framework for ascertaining the reliability of potential technosignatures by availing ourselves of recent cognate research in biosignatures. We demonstrate that ideal technosignatures must not only have low risk of stemming from false positives but also evince sufficiently high prior probability of existence. Given the inherent difficulties with estimating the latter, we highlight a few alternative metrics drawn from diagnostic testing such as the Youden index that bypass the requirement of explicitly calculating the prior. We apply the models (Bayesian or otherwise) to a select few technosignature candidates and show that artificial electromagnetic signals, chlorofluorocarbons, and artifacts perform well on this front. While these results may be along expected lines, we suggest that identifying and developing suitable approaches to further evaluate technosignature candidates is of considerable importance.

show abstract

“…We can exclude scenarios in which all G-dwarf stars would have been settled by now, but the possibility remains open that a Galactic Club exists across all K-dwarf or M-dwarf stars. The search for technosignatures in low-mass systems provides one way to constrain the presence of such a Galactic Club (e.g., Lingam & Loeb 2021;Socas-Navarro et al 2021;Haqq-Misra et al 2022;Wright et al 2022). Existing searches to-date have placed some limits on radio transmissions (e.g., Harp et al 2016;Enriquez et al 2017;Price et al 2020;Zhang et al 2020) and optical signals (e.g., Howard et al 2007;Tellis & Marcy 2015;Schuetz et al 2016) that might be associated with technological activity, but such limits can only weakly constrain the Galactic Club hypothesis.…”

Section: The K-dwarf Galactic Clubmentioning

confidence: 99%

Galactic Settlement of Low-mass Stars as a Resolution to the Fermi Paradox

Haqq-Misra¹,

Fauchez²

2022

Self Cite

View full text Add to dashboard Cite

An expanding civilization could spread rapidly through the Galaxy, so the absence of extraterrestrial settlement in the solar system implies that such expansionist civilizations do not exist. This argument, often referred to as the Fermi paradox, typically assumes that expansion would proceed uniformly through the Galaxy, but not all stellar types may be equally useful for a long-lived civilization. We suggest that low-mass stars, and K-dwarf stars in particular, would be ideal migration locations for civilizations that originate in a G-dwarf system. We use a modified form of the Drake equation to show that expansion across all low-mass stars could be accomplished in 2 Gyr, which includes waiting time between expansion waves to allow for a close approach to a suitable destination star. This would require interstellar travel capabilities of no more than ∼0.3 lt-yr to settle all M-dwarfs and ∼2 lt-yr to settle all K-dwarfs. Even more rapid expansion could occur within 2 Myr, with travel requirements of ∼10 lt-yr to settle all M-dwarfs and ∼50 lt-yr to settle all K-dwarfs. The search for technosignatures in exoplanetary systems can help to place constraints on the presence of such a “low-mass Galactic Club” in the Galaxy today.

show abstract

Searching for technosignatures in exoplanetary systems with current and future missions

Cited by 15 publications

References 172 publications

A Bayesian Analysis of Technological Intelligence in Land and Oceans

A Bayesian Analysis of Technological Intelligence in Land and Oceans

Technosignatures: Frameworks for Their Assessment

Galactic Settlement of Low-mass Stars as a Resolution to the Fermi Paradox

Contact Info

Product

Resources

About