# A Shiny New Method for SETI: Specular Reflections from Interplanetary Artifacts

## TL;DR

This paper proposes a novel method for detecting extraterrestrial artifacts in the Solar System by observing specular reflections or glints from artificial mirrors, using existing astronomical survey data.

## Contribution

It introduces a new technosignature detection approach based on specular reflections from interplanetary artifacts and estimates the observational reach of current surveys like Pan-STARRS1.

## Key findings

- Glints from artificial mirrors can be very bright but are rare and orientation-dependent.
- Pan-STARRS1 can detect interplanetary mirrors of about 10 m^2 within certain distances.
- Over years, Pan-STARRS1's cumulative coverage greatly increases the likelihood of detection.

## Abstract

Glints of light from specular reflection of the Sun are a technosignature of artificial satellites. If extraterrestrial intelligences have left artifacts in the Solar System, these may include flat mirror-like surfaces that also can glint. I describe the characteristics of the resulting flashes. An interplanetary mirror will appear illuminated for several hours, but if it is rotating, its glint may appear as a train of optical pulses. The resulting glints can be very bright, but they will be seen only if the mirror happens to reflect sunlight to the Earth. The detection of large mirrors is limited mainly by the fraction oriented to reflect sunlight toward Earth. I give rough calculations for the expected reach of each exposure of Pan-STARRS1, LSST, and Evryscope for mirror glints. A single exposure of Pan-STARRS1 has an effective reach of 10^-9 - 10^-7 AU^3 for interplanetary mirrors with effective areas of 10 m^2, depending on rotation rate. Over several years, Pan-STARRS1 might accumulate a reach ~10^5 times greater than this, as it tiles the sky and different mirrors enter and exit a favorable geometry.