JHK_s UKIDSS colour composite image of the centre of the nebula; K_s is red, H is green, and J is blue. The white contours indicate the centre of the extended 24 μm emission (levels of 400, 500, and 600 MJy sr⁻¹). The two candidate exciting stars, ex1 and ex2, are identified, as well as two other YSO candidates, #3 and #5, identified by Kang et al. (2009). The insert is an enlargement of the UKIDSS K_s image of ex1 and ex2.