THE HOMUNCULUS OF ETA-CARINAE - AN INTERACTING STELLAR WINDS PARADIGM

We simulate the origin and evolution of the bipolar nebula surrounding eta Car using numerical two-dimensional gasdynamical models. The gene ralized interacting stellar winds scenario, wherein a stellar wind int eracts with an aspherical circumstellar environment, is adopted. The e ruption wind of 1840-1860, which is taken to be spherically symmetric, interacts with a preeruption toroidal density environment. Using reas onable assumptions of initial conditions and eruption parameters based on archival data, we have performed over 30 simulations in an effort to bracket the initial parameters which produce models that best match observations. We find that models with high pole-to-equator density c ontrasts (> 100) and toroidal density configurations nicely account fo r the observed morphology and kinematics of the homunculus.