The Zeiss double refractor This telescope is mainly used to observe visual binary stars, conduct photometric studies on eclipsing binaries, image lunar craters, observe planets (Mars, Saturn and Jupiter) and to observe comet details and other heavy bodies. The telescope has two objective lenses with a diameter of 60 cm (24 in) each and a focal length of 10.7 m (35 ft). The Schmidt telescope (nicknamed the Bima Sakti, or "Milky Way" telescope) This telescope is used to study galactic structure, stellar spectra, asteroid studies, supernovae, and to photograph heavy bodies.