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 analyzing 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 7 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.

arXiv commentAccepted to be published in MNRAS

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Cited by in corpus (8)

• Anomaly Detection and Radio-frequency Interference Classification with Unsupervised Learning in Narrowband Radio Technosignature Searches
• A Data-Driven Search For Mid-Infrared Excesses Among Five Million Main-Sequence FGK Stars
• In Search of Extraterrestrial Artificial Intelligence Through Dyson Sphere-like structures around Primordial Black Holes
• High-resolution imaging of the radio source associated with Project Hephaistos Dyson Sphere Candidate G
• Ringworlds and Dyson spheres can be stable
• Ground to Dust: Collisional Cascades and the Fate of Kardashev II Megaswarms
• Wind Power as a Technosignature on M-dwarf Planets
• The Dyson Minds 2025 Workshop: SETI around Black Holes