Extreme Flaring of Starlink Satellites

TL;DR

This paper investigates the extreme brightness flares of Starlink satellites caused by sunlight reflection, analyzing their reflectance properties and applying findings to an incident reported as an unidentified aerial phenomenon.

Contribution

It provides the first detailed analysis of Starlink satellite flares using bidirectional reflectance modeling and applies this to explain an extreme flare incident.

Findings

Brightness of flares matches bidirectional reflectance models

Extreme flare can be explained by specular reflection

Findings help distinguish satellite flares from other aerial phenomena

Abstract

Starlink satellites can become extremely bright when sunlight reflects specularly to an observer on the ground. The observed brightness of such flares is consistent with a bidirectional reflectance function of the Starlink satellite chassis. These findings are applied to the case of an extreme flare that was reported as an Unidentified Aerial Phenomena by the pilots of two commercial aircraft.