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Making Habitable Worlds: Planets Versus Megastructures

Published online by Cambridge University Press:  20 January 2026

Raghav Narasimha PonnagantiOpen the ORCID record for Raghav Narasimha Ponnaganti[Opens in a new window],
Margarita SafonovaOpen the ORCID record for Margarita Safonova[Opens in a new window] and
Chandra Sivaram
Raghav Narasimha Ponnaganti*
Affiliation:
Indian Institute of Astrophysics, Bangalore, India
Margarita Safonova
Affiliation:
Indian Institute of Astrophysics, Bangalore, India
Chandra Sivaram
Affiliation:
Indian Institute of Astrophysics, Bangalore, India
*
email: narasimha.p@gmail.com
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Abstract

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With billions of planets in the galaxy, advanced civilizations could relocate planets within or into their planetary systems rather than destroy entire planetary systems to construct megastructures. Such shifts could create Strange Exoplanetary Architectures (SEA), with unusual planetary arrangements potentially indicating deliberate actions by extraterrestrial intelligence (ETI). Searching for biosignatures and technosignatures in these systems could be a promising method for detecting ETI activities.

Keywords

MegastructuresHabitable ZoneFree-Floating PlanetsService WorldsTechnosignatures

Information

Type
Contributed Paper
Information
Proceedings of the International Astronomical Union , Volume 20 , Symposium S387: (Toward) Discovery of Life beyond Earth and its Impact , December 2024, pp. 134 - 141
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Creative Commons
Creative Common License - CCCreative Common License - BY
This is an Open Access article, distributed under the terms of the Creative Commons Attribution licence (https://creativecommons.org/licenses/by/4.0/), which permits unrestricted re-use, distribution and reproduction, provided the original article is properly cited.
Copyright
© The Author(s), 2026. Published by Cambridge University Press on behalf of International Astronomical Union

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