A search for transient, monochromatic light from the Galactic plane

ABSTRACT The Galactic plane was searched for transient, monochromatic light at optical and near-IR wavelengths to detect pulses shorter than 1 s. An objective-prism Schmidt telescope of 0.28-m aperture a CMOS camera were used observe 973 square deg, with 8864 exposures 1-s each, within strip 2.1 deg wide along the plane, from longitude −4 +248 deg. All analysed sources using ‘difference image’ algorithm that yielded 11 candidate sources. found be associated either astrophysical emission-line objects or aircraft subsecond blinking lights. Our survey ‘rediscovered’ many Wolf–Rayet stars, M dwarf flare planetary nebulae. It also identified an aircraft, unknown type, apparently had nearly lamp xenon lamp. This would have revealed having power ∼180 GW (wavelength dependent) if emitted by 10-m laser located kiloparsec away. These non-detections including 10-deg region towards centre, add more 5000 nearby stars. Indeed, all-sky surveys (e.g. ionized gas, supernovae remnants, active galactic nuclei) lasers range average brightness, wavelength, cadence. absence beacons reveals SETI desert, notably intensely surveyed radio wavelengths.