[e.g., @heyer96]. The CO data cubes were given by M. Heyer and C. Brunt (through private communication). The data cubes of $^{12}$CO and $^{13}$CO were smoothed using a Gaussian function with a full-width at half-maximum of 3 pixels to improve sensitivity.

We also downloaded the [*Spitzer*]{} post-Basic Calibrated Data (PBCD) images at 3.6, 5.8, and 8.0 $\mu$m from the [*Spitzer*]{} Heritage Archive (ID: 50244; PI: G. Fazio). These images (plate scale $\sim$0$''$.6/pixel) were available only for an area of $\sim$5$'$.5 $\times$ $\sim$5$'$.5 hosting AFGL 5157.

Analysis and Results {#sec:data}
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Multi-band picture of AFGL 5157 {#subsec:u1}
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In order to probe the physical environment of AFGL 5157, multi-wavelength continuum images are carefully examined, which span from optical H$\alpha$, infrared to radio wavelengths.

### Multi-wavelength continuum images {#subsec:xu1a}

As highlighted in Section \[sec:intro\], in the direction of AFGL 5157, Figure \[fig1\]a summarizes previously reported features (i.e., infrared shell, dense core, and H[ii]{} region) within an area of $\sim$1.8 pc $\times$ $\sim$1.8 pc. A large-scale view of AFGL 5157 (size $\sim$13.5 pc $\times$ 13.5 pc) at 250 $\mu$m is shown in Figure \[fig1\]b. This sub-mm image shows the existence of embedded filaments. We highlight representative filaments using arrows in Figure \[fig1\]b. The 