1997A&A...324.1165Z

A new, small (6'x3') filamentary emission nebula of very low surface brightness (l= 197.0^o, b = -37.8^o) is found to be projected towards the center of a huge expanding (40km/s) HI shell (Brown et al. 1995) surrounding the Orion-Eridanus Bubble. Moderate quality spectra taken by us show low-excitation species but allow us to estimate the electron density (≃10²cm^–3). The spectra point to an excitation by a shock of low velocity (≃40km/s). No dust emission (IRAS) is seen at the position of our object, which could well be an outlying clump of material associated with the L1569 dust cloud at a distance of about 130±20pc, and which appears to be at the front side of the Bubble. We believe that our "Criss-Cross Nebula", dubbed so due to its specific morphology, might represent a very small interstellar dust cloud that is just in the process of destruction by the blast wave of a supernova that gave rise to the Orion-Eridanus Bubble and to some of its characteristics like the Eridanus soft X-ray enhancement. Known examples of clouds overrun by blast waves are exceedingly rare and a more detailed study of this new nebula is therefore highly recommended.