Abstract
The very dense H II condensation inside NGC 2175 (S 252) contains a bright star, V = 11.05 and a faint star, V = 14.15, separated by 16.2 arc seconds. Photographic and photoelectric photometry of the stars permits an estimate of the spectral types not earlier than B1.5 V and B9 V respectively. It seems doubtful whether the first star can excite the H II condensation. On two objective prism plates the fainter star shows intense emission lines. On Fabry-Perot interferograms (in Hα) the two stars fall within the innermost ring and appear of equal brightness. This circumstance allows an estimate of the energy radiated - in Hα of the faint star as 6.3 x 10^33 erg s-1 Spectra of the condensation have yielded velocities from the Hα line about 30 km s-1 more positive than those from the forbidden lines.
