Spitzer/IRAC 8 µm image of the three filaments in IC 1848 (G1–G3, left-to-right, respectively). Bright IRAC compact sources are clearly visible at the head of the filaments (white saturated spots in the image). Cyan contours show the [C II] 158 µm integrated line intensity observed with SOFIA/upGREAT. Contour levels are 8, 12, 18, and 27 K km s⁻¹, and typical 1σ noise levels are 3.3, 1.8, and 2.4 K km s⁻¹ in G1–G3, respectively. Blue stars mark the location of the three brightest 2MASS/WISE sources at the heads of the filaments, and the white arrow shows the direction toward the O6V ionizing star HD 17505.