Studying of the own rotation period changes of satellite "Ajisai" on the interval 1986-2017

Abstract

Purpose. The purpose of this work is to describe changes in own rotation of satellite Ajisai, compare results with data obtained in MMT-9 project, make analysis of all 31 year of available data. Methods . Light curves of satellite Ajisai was obtained by photometry method. All light curves was processed using Lomb-Scargle method to obtain period of own satellite rotation. Results. The results of research of the own rotation of the satellite Ajisai (NORAD ID 16908, ESA ID 86061A) from the moment of its launch into Earth's orbit in 1986 up to 2017 are presented. The periods of satellite own rotation are determined from the light curves which were obtained in the Laboratory of Space researches of UzhNU. These results are compared with the data of other foreign studies on this satellite. The general tendency of change of the period of own rotation during the satellite’s lifetime is analyzed. Methods of satellite own rotation definition are compared. Conclusions. More modern CCD photometry method, used in foreign studies of Ajisai satellite gives less accuracy than electrophotometry method used in LSR UzhNU mainly because of long exposures in CCD photometry. New parameters of exponential function that describe Ajisai spin decay is presented. Accuracy of this parameters are presented for the first time.