New data are presented on the morphology and ionization structure and kinematics of II Zw 40, a ‘detached extragalactic H II region’. They show a core–halo structure with the ionizing stars embedded in a small nucleus and a halo composed of small optically thick filaments. Direct plates show two tails protruding from this halo. This optical structure is interpreted as an interaction between two extremely small galaxies. This encounter would then be the cause of the present burst of star formation.
No takes yet. Share an insight, caveat, or question.
Baldwin et al. (1982) studied this question.