RK-800: History of the telescope

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The first version of the 0.8-m Ritchey-Chretien telescope with an aperture of F/16 was developed at the Crimean Astrophysical Observatory in 1983. A single-channel photometer was mounted on the telescope in 1986 and it laid the foundation for studying rapid fluctuations of atmospheric transparency. Observations of atmospheric extinction were carried out simultaneously at three telescopes - RK-800, AZT-11 and AZT-7 located at a distance of more than 600 m, the short-term variations in extinction were studied. Based on these observations, the curves of atmospheric extinction were found to vary by 0.025 magnitude, rapid variations take place within 3-5 minutes with an amplitude of 0.02 magnitude and are the main obstacle for the fundamental technique of photometry.

In 1993 a metal tube was replaced with a tube made of fiberglass plastic, which was designed under the guidance of V.P. Zhuravlev at the Feodosia Ship and Mechanical Plant.

The spectrophotometric observations of stars of various spectral types by means of a scanning spectrophotometer in the spectral range from 3000 to 7900 Å were carried out in the early 90s. In particular, in 1990 and 1993 spectrophotometric observations of symbiotic nova PU Vul were performed. The spectral energy distribution and physical parameters of atmospheres of the A main sequence stars with different infrared excesses in the IRAS filters were derived. Parameters of the dust shells were estimated based on spectrophotometry and JHKLM photometry. The spectral energy distribution in 111 late-type stars in the spectral range 3500-7600 Å was studied. The corresponding spectral atlas is to be found on the website of the Crimean Astrophysical Observatory. In 2011 the telescope was equipped with CCD camera with a set of UBVRI filters and was used in systematic observations of exoplanet transits.