Discovery of a Huge Young Stellar Object Interaction Region in Camelopardalis

Abstract

During the course of a wide-field VI survey of galaxies in the IC 342/Maffei Group, a large nebula, which looks like an inclined disk with a jetlike plume emerging from it, was discovered in Camelopardalis. The object is most prominent in I. The predominating disk component is 68 across, which corresponds to 4.0 ± 1.6 pc at the estimated distance of 2.0 ± 0.8 kpc (the Perseus Arm). The plume extends 38 (2.2 pc) outward from the core along a direction that is about 20° from the minor axis of the disk. The disk lies along the edge of a filament of dust and molecular gas in the Milky Way. The plume points toward the core of the filament. No large-scale emission is seen at Hα, and the nebula is invisible in Two Micron All Sky Survey (2MASS) images. About 30'' from the center of the disk is IRAS 04261+6339, which is a pair of unresolved Hα sources whose IRAS colors and spectra reveal them to be young stellar objects (YSOs). The northern of the two exhibits a near-infrared tail, which is 15'' (0.15 pc) long in H and directed 66° away from the plume. Although the stars are exposed, as in Class II YSOs, the spectral energy distribution of the pair rises beyond 2 μm, typical of Class I systems. It appears that they are transitional YSOs, with characteristics similar to those of Holoea (IRAS 05327+3404). The total brightness of the plume plus disk exceeds that of the stars by 1.6 mag in I, yet the V-I color is bluer by only 0.50 mag. Thus, the nebula cannot be a consequence of reflection, even allowing for differential extinction. It is tentatively identified as a remnant of an outflow from a binary YSO, glowing from the photoluminescence of silicon nanoparticles.