A Sky Brightness Model for the Starlink 'Visorsat' Spacecraft

TL;DR

This paper develops a brightness model for Starlink's VisorSat spacecraft based on engineering data and observational analysis, assessing its visibility across the sky and updating previous findings with new observations from 2021.

Contribution

It provides an updated, detailed brightness model for VisorSat, incorporating recent observations and analyzing its implications for visibility.

Findings

VisorSat brightness varies with design features.

Updated model suggests VisorSat can be brighter than previously estimated.

Implications for astronomical observations and satellite visibility are discussed.

Abstract

A model of the brightness of the visorsat Starlink spacecraft is presented based on published information on the engineering design and from analysis of 131 observations of individual visorsats in late 2020. Comments are offered on the implications of this model on the visibility of visorsat spacecraft across the sky. This is an updated and expanded version of analysis published in Research Notes of the AAS (2020). An additional section has been added in this version to consider observations made in June 2021 which indicate brighter visorsat magnitudes.