Sao Hạn (Vietnamese Year Stars) (越南星宿流年)

SAO HẠN — Vietnam's year-star system, the reason temples fill with cúng sao giải hạn ceremonies every first lunar month: nine stars (cửu diệu) take turns presiding over each person's year on a nine-year wheel per gender — nam opening La Hầu at tuổi 10 (the temple-flyer mnemonic), nữ opening Kế Đô — with the good/neutral/bad triads the tradition grades (Thái Dương·Thái Âm·Mộc Đức good; La Hầu·Kế Đô·Thái Bạch the caution stars — 'Thái Bạch quét sạch cửa nhà'). ANCHORED SIX WAYS against the published 2026 table: nam sinh 1990 → La Hầu, 1995 → Thái Dương, 2000 → Mộc Đức, nữ → Kế Đô, Thổ Tú, Thủy Diệu — all reproducing from tuổi mụ = year − birth + 1 on the canonical orders, asserted at load. Plus KIM LÂU by the famous 1-3-6-8 rule (the four harms: Thân, Thê, Tử, Lục Súc — consulted before weddings and house-building) and TAM TAI by the same clash-trine theorem the Korean 삼재 engine proves (Hợi Mão Mùi at Tỵ years — the two countries' folk presses agreeing on 2025 from one shared structure). The eight-hạn layer (Huỳnh Tuyền…Diêm Vương) and Hoang Ốc are DEFERRED by name — the published examples don't reduce to a linear cycle, and nothing is guessed. Vietnamese living custom for cultural reference — not fate, not advice. Pure computation, no LLM.

Cost: 2 TIAN Points per call. tRPC procedure saohan.year.