USING SYNTHETIC LIGHT CURVES OF ARTIFICIAL SATELLITE MODEL TO TEST THE PATTERNS METHOD FOR DETERMINING THE ROTATION AXIS ORIENTATION

In this paper we test a new method for determining the rotation axis direction in space for various resident space objects (RSOs). This method (Koshkin et al., 2024) is based on the structural analysis of the light curves of such RSOs and the search for similar fragments, called "photometric patterns", in observations obtained from one or several observatories simultaneously or over a short period of time. The method does not require prior knowledge of the RSO shape and does not impose strict requirements on the quality of observations, and this is its main advantage. First of all, this method is certainly applicable to rapidly rotating objects of complex shape with smooth surfaces. As a result, such RSOs are capable to reflect sunlight in a specular manner, when short-term brightness flares are present in the light curves forming a unique pattern. Identical patterns are observed when the angle between the phase angle bisector (PAB) and the rotation axis reaches the same values. However, the light curves of many RSOs have a significant diffuse component in addition to the specular flares. This diffuse component depends on both the phase angle value and the orientation of the phase angle plane relative to the RSO’s plane of rotation. This paper is devoted to checking the assumption that the structure and shape of diffuse-specular patterns will remain similar to themselves within certain limits of variation of the value of these two angles at moments of equality of the PABs’ latitude. The analysis is based on simulation using synthetic light curves of the RSO model, observed from several points on the Earth's surface.