Four features, 10 new SQL functions (174 → 184 objects), 29 test suites:
Saturn ring tilt: saturn_ring_tilt() exposes sub-observer latitude B'.
planet_magnitude() for Saturn now includes Mallama & Hilton Eq. 10
ring correction (-2.60|sin B'| + 1.25 sin²B'), removing the ~1.5 mag
globe-only caveat. IAU 2000 pole direction, ecliptic J2000 projection.
Conical shadow model: Replaces cylindrical shadow with umbra/penumbra
cones using Sun's finite angular size. Four new functions:
satellite_in_penumbra(), satellite_shadow_state(),
satellite_next_penumbra_entry/exit(). Existing eclipse functions are
backward compatible via narrower (more accurate) umbra boundary.
Rise/set event windows: Three SRFs returning TABLE(event_time, event_type)
for all rise/set events within a time window — planet_rise_set_events(),
sun_rise_set_events(), moon_rise_set_events(). Follows predict_passes()
SRF pattern. Optional refracted parameter, 366-day window limit.
Angular separation rate: Vincenty formula extracted to reusable helper.
eq_angular_rate() for generic finite-difference rate, planet_angular_rate()
for solar system body convenience (1-minute dt, handles Sun/planets/Moon).
162 → 174 SQL objects, 27 → 28 test suites, 3 new C source files.
Features:
- solar_elongation(body_id, ts): Sun-Earth-Planet angle [0,180] degrees
- planet_phase(body_id, ts): illuminated disk fraction [0,1]
- satellite_is_eclipsed/next_eclipse_entry/exit/eclipse_fraction:
cylindrical shadow model (Vallado §5.3) for Earth shadow prediction
- observing_night_quality(observer, ts): composite PL/pgSQL scoring
based on astronomical darkness duration and Moon interference
- moon_libration_longitude/latitude/position_angle/libration/subsolar_longitude:
optical libration from Meeus (1998) Ch. 53
Refactored magnitude_funcs.c to extract shared compute_planet_geometry()
used by magnitude, elongation, and phase — single VSOP87 evaluation per call.
All 28 regression suites pass. Zero compiler warnings.
The original implementation only used c1+c2 coefficients from the
simplified model. Mercury's 6th-order polynomial diverges badly
beyond ~60 deg phase angle with only 2 terms — returning -23 mag
at 130 deg (should be +1.1).
Now uses the complete piecewise models from the paper:
- Mercury: full 6th-order polynomial (Eq. 1)
- Venus: piecewise at 163.7 deg (Eq. 2/3)
- Mars: piecewise at 50 deg (Eq. 5/6)
- Jupiter: piecewise at 12 deg with log term (Eq. 7/8)
- Saturn: globe-only model (Eq. 11/12), ring tilt still not modeled
- Uranus: phase threshold at 3.1 deg (Eq. 14)
- Neptune: phase threshold at 1.9 deg (Eq. 17)
Bug found by astrolock: Mercury at superior conjunction (i=130.6 deg)
returned -23.3 mag instead of +1.1.
Twilight: 6 functions (civil/nautical/astronomical × dawn/dusk) reusing
the existing find_next_crossing() bisection search with Sun depression
angle thresholds (-6°, -12°, -18°). Returns NULL for polar regions
where the threshold is never reached.
Lunar phase: 4 functions computing Sun-Earth-Moon geometry from VSOP87
+ ELP2000-82B. Phase angle [0,360) via elongation + cross product
z-component for waxing/waning discrimination. 8 named phases in 45°
bins. Moon age approximated from phase angle and mean synodic month.
Planet magnitude: Mallama & Hilton (2018) polynomial model with VSOP87
heliocentric distances and phase angle via law of cosines. All 7
planets (Mercury-Neptune, excluding Earth). Saturn ring tilt not
modeled.
151 → 162 SQL objects. 26 → 27 test suites, all passing.
