Investigation of Nova Cygni 1975 (V 1500) at Abastumani. I. Photographic Observations of Spectra

On the night of August 30/31, 1975, one of the authors discovered a nova in the constellation Cygnus. Spectroscopic observations of the nova were made with a 70-cm meniscus telescope, using a 72-cm, 8°, objective prism and a diffraction spectrograph mounted at the Cassegrain focus. The radial velocity of expansion of the nova's shell turned out to be about 2000 km/sec and its mass was on the order of 10^-5 M and had a tendency to increase with time; we estimated the emission energy to be 5·10⁴⁴ erg and the kinetic energy of the shell to be 10⁴⁵ erg, while the electron temperature in the shell is 5000 K.