(a) IRAC 4.5 μm image of HH 54. Image center is at α(J2000) = 12 ^h55 ^m49 5 δ(J2000) = −76°56′22''. Individual knots are identified and labeled according to Giannini et al. (2006). Knot I, not seen on the NIR, is identified as the optical counterpart to HH 54I. (b) Temperature map of HH 54 based on IRAC color–color analysis for 2000 K ⩽ T⩽ 4000 K. The black contour levels are 2000 K, 2500 K, 3000 K, and 3500 K. The green line connecting the higher temperature knots A, B, and I points toward the proposed source IRAS 12496–7650.