Abstract
We present a comparison of outflows between a young stellar object (HH 240/241) and a post-AGB star (CRL 618). The outflows of these objects are narrow and similar in morphology, indicating that they may be driven by similar, but unseen, fast, collimated winds ejected from the central sources. We also present a simple, hydrodynamical simulation of a fast, collimated wind and compare it to the observations. We find that a fast, collimated wind with a small opening angle can indeed produce a narrow lobe similar to that of HH 240/241 and CRL 618.
