2007A&A...461..943S

TVRet was classified as a cataclysmic variable due to an outburst observed in 1977. We intended to confirm this classification and derive some basic properties of the system. Low resolution optical spectra were obtained for a spectral classification of the object. We find that the object is not a cataclysmic variable but an emission line galaxy with a redshift z=0.0964. An R-image taken in very good seeing conditions shows that the object is extended. We show that TVRet is a blue dwarf galaxy, probably compact, with an absolute magnitude of M_B=-17.5, a metallicity of 0.12 solar, and an average temperature of 1.3x10⁴K. The line ratios place it among the HII galaxies, although close to the border of the Seyfert2s. The outburst, which was observed in 1977, could thus be explained by a supernova explosion. However, with an absolute magnitude around M_B=-21, it was an extremely bright one.