The Crimean Astrophysical Observatory: Post-War Reconstruction and Early Observations

On 30 June 1945, the Soviet government decided to construct the Crimean Astrophysical Observatory. It inherited the observing tradition of Simeiz while rebuilding instruments and research conditions after wartime destruction. The one-metre reflector formerly used at Simeiz for binary stars and stellar radial velocities had been taken to Germany during the war and was beyond repair when found afterward.

Solar observation also had pre-war foundations. A Dallmeyer photoheliograph installed in 1932 allowed Albitsky and colleagues to record daily sunspot and facula counts and areas for Soviet and international programmes. A Hale spectrohelioscope introduced in 1938 extended coverage to chromospheric activity in the hydrogen H-alpha line. War interrupted these routine observations.

References: [1] [3]

Post-war work proceeded at two sites: Simeiz resumed earlier observations, while Nauchny in the Crimean mountains became a new observatory. Participants recalled that the new site initially was almost empty ground. Telescopes, housing and working facilities appeared progressively, with a research institution and residential settlement developing together. Grigory Shajn and Andrei Severny were principal organizers.

Severny became deputy director in 1949 and director in 1952, connecting solar-instrument development with research programmes. By the mid-1950s, a solar tower telescope, coronagraph and stellar instruments were operating, but data reduction still depended heavily on abacuses, slide rules, mechanical calculators and planimeters. Expanded observing capacity also increased measurement and computational labour.

References: [2]

The Zeiss reflector transferred after the war had originally been built for Berlin's Babelsberg Observatory. With an aperture of 1,220 millimetres, about 48 inches, it helped replace capabilities lost with Simeiz's destroyed one-metre telescope. It was later commonly called the 50-inch telescope. Combined with a spectrograph, it spread starlight into spectral lines for comparison of physical properties.

Shajn's programme on Galactic structure ran from 1950 to 1965, producing thirteen catalogues containing photometric and spectral characteristics of approximately 35,000 stars. A twin 400-millimetre astrograph performed observations: one tube carried an objective prism for stellar spectra, while the other recorded direct images. Different combinations of photographic emulsions provided photometry in three bands.

References: [3]

The spectrohelioscope was among the first instruments restored at Simeiz, resuming regular observations on 1 May 1947. Structural modifications also enabled photographic recording of solar spectra. Regular spectroscopy beginning in 1952 supplied Severny, Mustel and colleagues with data on physical conditions in flares, plages and prominences.

In 1948, Severny and Gilvarg built an interference-polarizing filter with a passband of approximately 0.5 ångströms, allowing rapid solar activity to be recorded continuously on film. Nauchny's KG-1 coronagraph was completed in 1950. Used with the filter and a movie camera, it provided many hours of daily observations. Shaposhnikova and Ogir worked with it over a long period, accumulating images of flare development, motion and eruptions.

References: [1]

The BST-1 solar tower telescope entered service in 1954 with two spectrographs and a double spectroheliograph. Severny, Ivanov-Kholodny, Khokhlova, Stepanyan and others carried out spectroscopy there. The instrument connected continuous records of the Sun's changing appearance with study of physical processes inside active regions.

In 1955, Severny and Stepanov began using BST-1 to observe sunspot magnetic fields, initially photographically and later visually. In 1956, they and Nikulin built a magnetograph for weak solar fields. Spectra, images and magnetic records gradually converged into the observatory's main early methods for solar physics.

References: [1]

Long-term programmes left glass plates and observing logs. The objective-prism collection in the spectral archive contains roughly a thousand spectral plates taken by different astrographs between 1929 and 1965, many from Shajn's programme. Information on dates, targets and instruments allows years of observations to be reorganized by object.

Later digitization matched scanned images with logs and published papers, converted pixel coordinates into spectral wavelengths and provided access through astronomical software such as Aladin. Records from pre-war telescopes, restored post-war equipment and new-site instruments thus remain research material that can be calibrated, compared and reanalysed.

References: [3]