Investigating the correlation between the motions of the images of close stars for laser communications experiments with the artemis satellite

Abstract

We investigated the correlation between the motions of the images of the components of the double star Gem. The angular distance between the components (4.8) corresponds approximately to the laser communications experiments with the geostationary Artemis satellite. The images were ac- quired with CCD cameras at the ESA's Optical Ground Station (the Canary Islands) and at the AZT-2 telescope of the Main Astronomical Observatory (Kyiv, Ukraine). Short exposures were made every second with narrow filters at a wavelength of about 850 m. Mean photometric positions of the Gem component images and their deviations were determined, and the correlation coefficients for the dis- placements of two images in the X and Y coordinates were calculated: K X = 0.96 and K Y = 0.95. The defocusing of the images was examined with the use of their full widths at half-maximum. We demon- strate that the atmospheric turbulence in the laser communications experiments with the geostationary satellite Artemis can be compensated for with the use of the data on the image motion observed in the di- rection toward the visible position of the satellite.