Multicolor photometry of geosynchronous satellites and application on feature recognition

Multicolor photometric observations of Geosynchronous Earth Orbit (GEO) satellites in the CCD image have been performed experimentally using the Schmidt telescope at Xing-long Observatory of National Astronomical Observatories, Chinese Academy of Sciences. The data have been reduced and the results have been analyzed. Compared the results of 4 satellites observed, it can be concluded that there are significant differences between the intensity curves and color indices of objects with different bus types. And the curves of single object observed during 2 nights have relatively strong similarity. The correlation coefficients are also evaluated, which quantify and verify the conclusion above. The results indicate that multicolor photometric characteristic of GEO satellites may be used as a method of object feature recognition. Further analysis by reducing the filters from 10 to 5 has been conducted to investigate whether a smaller number of these filters can produce the same result. The results show 5 filters also can partly distinguish satellites, but with less discrimination. More observations will be performed in order to further study and improve the method of space object identification in the future.