Bright rimmed globules and their more evolved cousin, the cometary globule, represent fascinating dynamic structures formed by the interplay of cold molecular clouds and hot ionizing stars.
Typically the head of the globule faces a hot O-type star. Intense radiation from the star boils away lower density gas from the head. The evaporated rim of gas becomes ionized by the stars ultraviolet flux forming a bright glowing rim we associate with many of these globules like LDN 1622 (Beverly Lynds’ Dark Nebulae Catalog) .
The Orion superbubble contains dozens of Cometary Globules illuminated by OB stars within the Orion OB1 association. L1622 is superimposed on the northern part of Barnard’s Loop at the northeastern periphery of the Orion B molecular cloud. LDN 1622 is actively forming young stars.The most conspicuous YSO (Young Stellar Object) in LDN 1622 is HBC 515, located at the head of the cometary cloud facing the Orion OB1 association.
A prominent reflection nebula opens toward the southwest. There are also several faint Herbig-Haro objects north and west of HBC 515.