Nikolay Koshkin, Astronomical Observatory of Odesa I.I. Mechnikov National University; Leonid Shakun, Astronomical Observatory of Odesa I.I. Mechnikov National University; Oleksandr Kozhukhov, National Space Facilities Control and Test Center of State Space Agency of Ukraine; Oleksandr Bryukhovetskyi, National Space Facilities Control and Test Center of State Space Agency of Ukraine; Roger Spinner, s2a systems; Elena Korobeynikova, Astronomical Observatory of Odesa I.I. Mechnikov National University; Seda Melikyants, Astronomical Observatory of Odesa I.I. Mechnikov National University; Svetlana Strakhova, Astronomical Observatory of Odesa I.I. Mechnikov National University
https://doi.org/10.64861/ZGOD2329
Keywords: LEO, Space Debris, Photometry
Abstract:
Studying the kinematic and dynamic behavior of resident space objects (RSO), including their rotational motion, is an important component of space situational awareness (SSA). Therefore, developing effective methods for remotely measuring the rotational motion parameters of various RSO is crucial for improving our understanding of the state of many different space objects.
We are developing a new method for determining the spatial orientation of a RSO’s rotation axis, called the “photometric patterns” method.
If similar segments (a photometric patterns) can be identified in several light curves of a rotating satellite, this may indicate that the satellite’s rotation axis, direction to Sun, and direction to observer form identical configurations at these moments. However, when the photometric pattern is formed by specular reflection from different surface areas of a rotating RSO, the pattern’s shape depends almost exclusively on the angle between the rotation axis and the phase angle bisector (PAB). This condition greatly simplifies the problem, although it is strictly satisfied only in the absence of mutual shading between surface facets reflecting sunlight. If we have enough light curves of a satellite obtained over a relatively short time interval and we can detect several identical photometric patterns of different types by comparing them, so we can attempt to determine the mean spatial direction of the satellite’s rotation axis at that time. This does not require any information about the shape of the satellite.
This report will describe an algorithm for working with observed light curves to correctly search for patterns of different types and prepare the data for the method of searching for the satellite’s rotation axis. The developed pipeline will be applied to observed light curves of satellites of various shapes, including the Ajisai spacecraft.
Date of Conference: September 15-18, 2026
Track: Satellite Characterization