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

TL;DR

This paper reports the detection of a signal-of-interest near Proxima Centauri during a SETI search, which was ultimately attributed to local interference, marking the most sensitive search for radio technosignatures on a star target.

Contribution

It presents the most sensitive radio technosignature search towards Proxima Centauri and discusses a candidate signal with characteristics similar to hypothesized extraterrestrial signals.

Findings

Detected a narrowband signal at ~982 MHz during observations.

The signal was ultimately identified as local interference.

This represents the most sensitive search for radio technosignatures on a star.

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.