The Local Galactic Transient Survey Applied to an Optical Search for Directed Intelligence

Abstract

We discuss our transient search for directed energy systems in local galaxies, with calculations indicating the ability of modest searches to detect optical Search for Extraterrestrial Intelligence (SETI) sources in the closest galaxies. Our analysis follows Lubin (2016) where a messenger civilization follows a beacon strategy we call "intelligent targeting." We plot the required laser time to achieve an SNR of 10 and find the time for a blind transmission to target all stars in the Milky Way to be achievable for local galactic civilizations. As high cadence and sky coverage is the pathway to enable such a detection, we operate the Local Galactic Transient Survey (LGTS) targeting M31 (the Andromeda Galaxy), the Large Magellanic Cloud (LMC), and the Small Magellanic Cloud (SMC) via Las Cumbres Observatory's (LCO) network of 0.4 m telescopes. We explore the ability of modest searches like the LGTS to detect directed pulses in optical and near-infrared wavelengths from Extraterrestrial Intelligence (ETI) at these distances and conclude a civilization utilizing less powerful laser technology than we can construct in this century is readily detectable with the LGTS's observational capabilities. Data processing of 30,000 LGTS images spanning 5 years is in progress with the TRansient Image Processing Pipeline (TRIPP; Thomas et al. (2025)).

arXiv comment8 pages, 7 figures, 1 table

References in corpus (14)

• Measuring Reddening with SDSS Stellar Spectra and Recalibrating SFD
• An updated analytic model for the attenuation by the intergalactic medium
• The Dark Energy Survey Image Processing Pipeline
• The Luminosity Profile and Structural Parameters of the Andromeda Galaxy
• The Breakthrough Listen Search for Intelligent Life: Observations of 1327 Nearby Stars over 1.10-3.45 GHz
• The Panchromatic Hubble Andromeda Treasury. VII. The Steep Mid-Ultraviolet to Near-Infrared Extinction Curve in the Central 200 pc of the M31 Bulge
• Discovery of an intermediate-luminosity red transient in M51 and its likely dust-obscured, infrared-variable progenitor
• Panoramic optical and near-infrared SETI instrument: overall specifications and science program
• Interstellar communication. X. The colors of optical SETI
• An optical search for transients lasting a few seconds
• The Hubble Catalog of Variables (HCV)
• Panoramic SETI: Program Update and High-Energy Astrophysics Applications
• Variability search in M 31 using Principal Component Analysis and the Hubble Source Catalog
• The Search for Directed Intelligence