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arXiv · 2111.08007

A radio technosignature search towards Proxima Centauri resulting in a signal-of-interest

Shane Smith·Danny C Price·Sofia Z Sheikh·Daniel J Czech·Steve Croft·David DeBoer·Vishal Gajjar·Howard Isaacson·Brian C Lacki·Matt Lebofsky·David HE MacMahon·Cherry Ng·Karen I Perez·Andrew PV Siemion·Claire Isabel Webb·Jamie Drew·S Pete Worden·Andrew Zic
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Abstract

The detection of life beyond Earth is an ongoing scientific endeavour, with profound implications. One approach, known as the search for extraterrestrial intelligence (SETI), seeks to find engineered signals (`technosignatures') that indicate the existence technologically-capable life beyond Earth. Here, we report on the detection of a narrowband signal-of-interest at ~982 MHz, recorded during observations toward Proxima Centauri with the Parkes Murriyang radio telescope. This signal, `BLC1', has characteristics broadly consistent with hypothesized technosignatures and is one of the most compelling candidates to date. Analysis of BLC1 -- which we ultimately attribute to being an unusual but locally-generated form of interference -- is provided in a companion paper (Sheikh et al., 2021). Nevertheless, our observations of Proxima Centauri are the most sensitive search for radio technosignatures ever undertaken on a star target.

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Shane Smith, Danny C Price, Sofia Z Sheikh, Daniel J Czech, Steve Croft, David DeBoer, Vishal Gajjar, Howard Isaacson, Brian C Lacki, Matt Lebofsky, David HE MacMahon, Cherry Ng, Karen I Perez, Andrew PV Siemion, Claire Isabel Webb, Jamie Drew, S Pete Worden, Andrew Zic. 2021-11-15. A radio technosignature search towards Proxima Centauri resulting in a signal-of-interest. https://doi.org/10.1038/s41550-021-01479-w

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