2004A&A...427..849C

The KW object, which has been one of the most puzzling infrared sources for three decades, has been resolved into a system of two early B-type stars with a projected separation of 2600AU. While the more luminous component shows a huge IR excess due to circumstellar dust, the fainter one displays X-ray emission. The system is deeply embedded (A_V∼24mag) in the molecular cloud M17SW and associated with an IR reflection nebula. A radiative transfer model of the spectral energy distribution of the IR excess object requires a stellar source of 5.1x10³L_☉ - equivalent to a B0 star - surrounded by 10M_☉ of circumstellar material. The KW object is associated with a small cluster of about 150 red stars. The stellar density within 0.1 pc is >2.4x10³pc^–3. From all new evidence we suggest that the KW object is one of the youngest, most deeply embedded Herbig Be stars known to date.