Combined Spitzer IRAC and WISE mosaic three-color view of HB 3 as seen in the IRAC 3.6 μm (blue), IRAC 4.5 μm (green), and WISE 12 μm (red). The IRAC 4.5 μm includes shocked molecular hydrogen emission and highlights the regions where the SNR HB 3 interacts with molecular clouds to the east. Bright H₂ filaments appear along the eastern and southern shells, while less filamentary structures are seen along the boundary with the H II region. The eastern and southern filaments along the shell of IRAC-2 show the flux density ranges between 0.3–1.5 and 0.3–0.95 MJy sr⁻¹, respectively. The background has a typical scale of 0.2 MJy sr⁻¹.