ON THE ADVANTAGES OF PHOTOMETRIC OBSERVATIONS OF THE GEOSTATIONARY SATELLITES AT SMALL PHASE ANGLES

As a rule, to determine photometric and dynamic characteristics of geostationary satellites required for their identification, long-lasting (from a half of the year to one year) photometric observations are needed at GSS different positions relative to the observer. The au- thors suggest conducting photometric measurements of GSS when they enter and exit the Earth's shadow near equinoxes. On these dates the GSS brightness increases by several magnitudes, so the use of telescopes with a mirror diameter of 50-70 cm can be effective. For shorter periods it is possible to get more information about the reflective properties of the object than during long-term observa- tions at large phase angles. Several examples of photomet- ric and dynamic characteristics of several GSS obtained near equinoxes are presented here.