SIMBAD references

High and low resolution spectroscopy, together with narrow and broad band imaging have been acquired for the unusual outflow source NGC 7026. We find evidence for appreciable changes in excitation, and a highly variable emission structure, consistent in part with observed variations in electron density. The mean electron density is found to be n_e=2.05x10³cm^–3, whilst the mean extinction is A_v=2.0mag. The outflow kinematics match the optical structure in suggesting an extremely complex flow, explainable in terms of four separate outflow centres distributed at the extremities of an inner spheroidal shell. Such features may constitute an advanced phase in the break-up of the primary shell, and eventually lead to the formation of a more typical bipolar outflow structure.