The Most Sensitive SETI Observations Toward Barnard's Star with FAST

Abstract

Search for extraterrestrial intelligence (SETI) has been mainly focused on nearby stars and their planets in recent years. Barnard’s star is the second closest star system to the Sun and the closest star in the Five-hundred-meter Aperture Spherical radio Telescope (FAST) observable sky which makes the minimum Equivalent Isotropic Radiated Power required for a hypothetical radio transmitter from Barnard’s star to be detected by FAST telescope a mere 4.36 × 108 W. In this paper, we present the FAST telescope as the most sensitive instrument for radio SETI observations toward nearby star systems and conduct a series of observations to Barnard’s star (GJ 699). By applying the multibeam coincidence matching strategy on the FAST telescope, we search for narrow-band signals (∼Hz) in the frequency range of 1.05–1.45 GHz, and two orthogonal linear polarization directions are recorded. Despite finding no evidence of radio technosignatures in our series of observations, we have developed predictions regarding the hypothetical extraterrestrial intelligence signal originating from Barnard’s star. These predictions are based on the star’s physical properties and our observation strategy.

COSMIC: An Ethernet-based Commensal, Multimode Digital Backend on the Karl G. Jansky Very Large Array for the Search for Extraterrestrial Intelligence

“…Overall, there are at least 12 radio telescopes worldwide with dedicated search for extraterrestrial intelligence (SETI) programs, expanding the search over a variety of wavelengths, sensitivities, and approaches (e.g., Johnson et al 2023;Tao et al 2023). Many radio telescopes are trending toward Ethernet-based digital architecture with multicasting capabilities to increase the scientific output through simultaneous commensal observation and processing with potential use by the SETI community.…”