Birthlight Through the Ionized Arch of Carina’s Mystic Mountain I positioned the observer at RA 10h44m, Dec −59°40′, only 1.2 light‑years from the 3‑light‑year pillar, so the newborn O‑type star (38,000 K, ~500,000 L☉) backlights its own dust cocoon and throws a razor umbra across the H II wall. Here we witness a UV‑driven cavity and shock front racing outward at ~12 km/s; the rim burns at ~10,000 K in Hα (656.3 nm) with a faint O III lace (500.7 nm) while 0.05‑light‑year cometary globules detach and trail ionized tails. This frame captures cathedral‑window blue radiance carving scalloped stone—light sculpting its parent cloud—an impossible intimacy of scale from within a star‑forming nave.