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To probe the star formation process, we present an observational investigation of the Pillar IV and an ionized knot HH 216 in the Eagle Nebula (M16). Pillar IV is known to host a Class I protostar that drives a bipolar outflow. The outflow has produced the bow shock, HH 216, which is associated with the red-shifted outflow lobe. The JWST near- and mid-infrared images (resolution ∼0 |${_{.}^{\prime\prime}}$| 07–0 |${_{.}^{\prime\prime}}$| 7) reveal the protostar as a single, isolated object (below 1000 au). The outer boundary of Pillar IV is depicted with the 3.3 |$\mu$| m Polycyclic aromatic hydrocarbon (PAH) emission. HH 216 is traced with the 4.05 |$\mu$| m Brα and the radio continuum emission; however, it is undetected with 4.693 |$\mu$| m H2 emission. HH 216 seems to be associated with both thermal and non-thermal radio emissions. High-resolution images reveal entangled ionized structures (below 3000 au) of HH 216, which appear to be located towards termination shocks. New knots in 4.693 |$\mu$| m H2 emission are detected and are mainly found on Pillar IV's northern side. This particular result supports the previously proposed episodic accretion in the powering source of HH 216. One part of the ionized jet (extent ∼0.16 pc) is discovered on the southern side of the driving source. Using the 12CO(J  = 1–0), 12CO(J  = 3–2), and 13CO(J  = 1–0) emission, observational signposts of cloud-cloud collision (or interacting clouds) towards Pillar IV are investigated. Overall, our results suggest that the interaction of molecular cloud components around 23 and 26 km s−1 might have influenced star formation activity in Pillar IV. [ABSTRACT FROM AUTHOR]

We report the observational findings of the Sh2-112 H ii region by using the multiwavelength data analysis ranging from optical to radio wavelengths. This region is powered by the massive O8V-type star BD +45 3216. The surface density distribution and minimum spanning tree analyses of the young stellar object (YSO) candidates in the region reveal their groupings toward the western periphery of the H ii region. A GMRT radio continuum emission peak is found toward the northwest boundary of the H ii region and is investigated as a compact/ultracompact H ii region candidate powered by a B0–B0.5-type star. Toward the southwest direction, a prominent curved rim-like structure is found in the Hα image and GMRT radio continuum maps, where the H2 and 13CO emission is also observed. These results suggest the existence of the ionized boundary layer (IBL) on the surface of the molecular cloud. This IBL is found to be overpressured with respect to the internal pressure of the surrounding molecular cloud. This implies that the shocks are propagating/propagated into the molecular cloud, and the young stars identified within it are likely triggered due to the massive star. It is also found that this region is ionization-bounded toward the west and density-bounded toward the east. Based on the distribution of the ionized gas, molecular material, and YSO candidates, we propose that the Sh2-112 H ii region is a good candidate for the blister-type H ii region that has been evolved on the surface of a cylindrical molecular cloud. [ABSTRACT FROM AUTHOR]