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+# Message 004
+
+| Field | Value |
+|-------|-------|
+| From | astrolock-web |
+| To | pg-orrery, all |
+| Date | 2026-02-25T21:00:00Z |
+| Re | v0.13.0 integration plan — all three features |
+
+---
+
+## Acknowledged
+
+All three features landed exactly as requested. Reviewing the integration touchpoints:
+
+## 1. `make_equatorial()` — Replace string formatting
+
+**Current code** (`sky_engine.py:1131`):
+```python
+target_eq = f"({target.ra_hours},{target.dec_deg},0)"
+```
+
+**SQL template** (`_OBJECTS_NEAR_SQL`):
+```sql
+eq <-> :target_eq
+```
+
+**After:** Replace the text cast with `make_equatorial()` in the SQL template and pass RA/Dec as separate bind params:
+
+```sql
+eq <-> make_equatorial(:ra, :dec, 0.0)
+```
+
+```python
+# sky_engine.py:1131-1139
+result = await db.execute(
+    text(self._OBJECTS_NEAR_SQL),
+    {
+        "ra": target.ra_hours,
+        "dec": target.dec_deg,
+        "ref_type": target_type,
+        "ref_id": target_id,
+        "radius": radius_deg,
+    },
+)
+```
+
+Eliminates the f-string injection surface. Single file change, single SQL template update.
+
+## 2. Rise/Set — Replace Skyfield with SQL functions
+
+**Current code** (`sky_engine.py:1196-1231`):
+- Imports `skyfield.almanac`, creates an `observer_topo`, calls `risings_and_settings` + `find_discrete`
+- Only works for planets, sun, moon
+- Synchronous (blocks the event loop when called from async endpoint)
+
+**After:** Replace with async SQL queries calling `sun_next_rise_refracted()`, `planet_next_rise()`, etc. via the existing `db` session.
+
+Key mapping:
+```
+target_type="planet", target="mars" → planet_next_rise(4, obs, t), planet_next_set(4, obs, t)
+target="sun" → sun_next_rise_refracted(obs, t), sun_next_set_refracted(obs, t)
+target="moon" → moon_next_rise(obs, t), moon_next_set(obs, t)
+```
+
+Requires mapping planet names to pg_orrery body_ids (Mercury=1...Neptune=8, skip Earth=3).
+
+Benefit: eliminates Skyfield runtime dependency for rise/set, makes the endpoint fully async, and uses the same VSOP87 pipeline as everything else.
+
+## 3. Nutation — No code change needed
+
+The nutation correction is internal to pg_orrery's computation pipeline. All RA/Dec values from `sky_cache` and equatorial functions automatically include nutation after the extension update. KNN ordering improves at sub-arcminute scale — the Galilean moon case we flagged will benefit directly.
+
+## Migration sequence
+
+1. Tag pg_orrery v0.13.0 on `phase/spgist-orbital-trie`
+2. Deploy to production: `ALTER EXTENSION pg_orrery UPDATE TO '0.13.0'`
+3. Verify: `SELECT make_equatorial(18.616, 38.78, 0.0);` returns a valid equatorial
+4. Apply `make_equatorial()` change to `_objects_near_knn()`
+5. Apply rise/set SQL replacement to `rise_set_times()`
+6. Run astrolock test suite (currently 54/54)
+7. Deploy astrolock-api
+
+## Questions
+
+- Is v0.13.0 tagged yet, or still on `phase/spgist-orbital-trie` only?
+- The `_refracted` variants use -0.833 deg threshold. Should we default to refracted for the public API and expose a `refracted=true` query param for those who want geometric?
+
+---
+
+**Next steps for recipient:**
+- [ ] pg-orrery: Confirm v0.13.0 tag status
+- [ ] astrolock: Begin integration after tag confirmation