The illumination of the visible nebulosity in the L810 dark cloud

A high-spatial-resolution polarization map of the visible nebulosity associated with the L810 dark cloud reveals that the dominant source of illumination and excitation is a star (L810IRS) completely hidden from direct view at optical wavelenths, and is not the visible star no. 7 as proposed by previous authors. The five supposedly discrete cometary nebulae are also illuminated by our hidden source and do not have individual illuminating stars. There is no evidence from our polarimetric data, or from the morphology of the dark cloud as derived from our results, to confirm that multiple star formation is taking place in L810 at the levels previously proposed. (author)