Abstract
If we are to understand the origins of emission line jets from young stars we have to probe their immediate circumstellar environments on scales of 10AU or less. Although this is difficult to do in the case of highly embedded stars, optically visible outflow sources, such as classical T Tauri stars and Herbig Ae/Be stars, sometimes offer us a window on their ``central engines''. Here in particular forbidden emission lines are an extremely useful diagnostic. Major differences, for example, can be seen in excitation conditions, velocity, opening angles, and so on between jets and counterjets close to their source. Moreover, at the source we observe not only high-velocity (jet) emission but also lower-velocity outflows moving at speeds close to the systemic velocity of the star. The origin of this low-velocity emission remains controversial. Here we briefly review recent findings in this area using HST imaging and spectroscopy as well as spectro-astrometrical observations from the ground. The optical outflow from DGTau will be used as an example and recent HST observations of this young star will be examined in the light of current models.
