The National Astronomical Observatory – Rozhen (abbreviation: NAO – Rozhen) is the largest astronomical observatory in Southeastern Europe and on the Balkan Peninsula.
The National Astronomical Observatory Rozhen was officially opened on 13 March 1981, but regular observational activity under scientific programmes started in September 1979. It is Bulgaria’s largest single investment in scientific infrastructure (over BGN 12 million) and is still the largest astronomical observatory in the Balkans and in this region of South-Eastern Europe in general. Located in the Rhodope Mountains, it was built on Mt. It is situated on the summit of the Rhodope Mountains, on the summit of Mt. It is maintained by the Institute of Astronomy of the Bulgarian Academy of Sciences.
It is equipped with 6 telescopes: universal 2 m Ritchey-Chretien-Coude (RCC or RKK) reflector of Carl Zeiss Jena, 50/70 cm Schmidt, 60 cm Cassegrain, self-built 15 cm solar coronagraph, 30 cm MEADE, 18 cm Meniscas Cassegrain. NAO Rozhen provides observations on a wide class of astronomical and astrophysical tasks – from dynamics and physics of solar system bodies, to extragalactic studies: asteroids and comets, spectra of stars of different classes and types of variability, star clusters, nearby and distant galaxies, quasars.