Optical observations of small spacecraft and space debris at ISTP SB RAS Sayan observatory

Launch of several thousands of small spacecraft as part of satellite groups of various companies (OneWeb, SpaceX, etc.) is expected in the coming years. They will significantly increase the “population” in the low-orbit region. The spacecraft are designed mainly to provide telecommunications and remote sensing of Earth from space. They have a short lifetime. The use of high-speed sCMOS (scientific complementary metal-oxide-semiconductor) detectors in combination with medium diameter optical telescopes provides high temporal resolution, which allows us to get detailed brightness light curves and to estimate the state of small spacecraft. We present the technique and results of photometric measurements of small spacecraft obtained with the 1.6-meter AZT-33IK telescope of ISTP SB RAS Sayan Solar Observatory. Photometric measurements are shown to be an important source of information at various operational stages of satellites.