site.btaRozhen National Astronomical Observatory Celebrates 45th Anniversary

The Rozhen National Astronomical Observatory celebrates on Friday 45 years since its opening.

Opened on March 13, 1981, the largest astronomical complex in Southeast Europe has since become Bulgaria’s leading center for astronomical observation and research, National Astronomical Observatory Rozhen Director Nikola Petrov told BTA. He said the observatory’s two-meter telescope was considered state of the art worldwide at the time of its inauguration.

Petrov said the observatory is now focused mainly on optical astronomy, conducting research in the visible light spectrum. Over the years, the complex has experienced both growth and setbacks, but in recent years it has modernized its equipment and expanded its scientific infrastructure.

In July 2023, a new optical telescope for night observations with a mirror diameter of 1.5 meters was put into operation at the observatory. An 80-centimeter telescope is due to be officially inaugurated in 2026, replacing a 60-centimeter instrument and enabling more precise observations, including of active formations on the Sun. The observatory also operates several smaller telescopes used for scientific research.

Petrov also announced that the construction of the first radio telescope in Bulgaria is expected to begin this year. The facility will join a major European network of radio telescopes, enabling observations in another part of the electromagnetic spectrum. Petrov said that if the project proceeds as planned, the radio telescope could become operational by the end of the year.

From March 5, 2026, the National Astronomical Observatory Rozhen has been open to visitors. Until the start of the summer season, visits are available from Thursday to Sunday between 10 a.m. and 4 p.m., with groups admitted every hour. From June, the observatory will welcome visitors daily except on Tuesdays, Petrov said.