Known Bugs and Limitations #
Documented issues in LibEphemeris. These are tracked and will be addressed in future releases where possible.
Active Bugs #
No active bugs at this time.
Fixed Bugs (v1.0.0) #
True Node distance (FIXED) #
The LEB fast path used mean orbital elements for True Node distance, causing ~3e-4 AU errors. Now uses full osculating orbit calculation from JPL DE data. Error reduced from 3.25e-4 AU to ~1.5e-7 AU (2000x improvement).
Sun heliocentric (FIXED) #
Previously, swe_calc(jd, SE_SUN, SEFLG_HELCTR) returned ~126° longitude
(garbage from arctan2 of near-zero values). Now correctly returns (0,0,0,0,0,0).
Uranian geocentric bodies (FIXED) #
Previously, swe_calc(jd, 40, SEFLG_SPEED) without SEFLG_HELCTR raised
UnknownBodyError. Geocentric conversion path added for all 8 Uranians (40-47).
Horizons Backend Limitations #
These are inherent to the Horizons API approach, not bugs:
| Limitation | Details |
|---|---|
| Moon velocity | ~0.001 deg/day difference vs analytical derivative (numerical differentiation) |
| Heliocentric offset | ~0.01-0.03" systematic difference (Horizons Sun center vs Skyfield SSB offset) |
| Requires internet | No offline fallback (use LEB or Skyfield for offline) |
| Latency | ~300-600ms first chart, cached afterward |
| Unsupported bodies | True Node (11), Oscu Apogee (13), Interp Apogee/Perigee (21,22), fixed stars, planetary moons — fall through to Skyfield |
Full details: Horizons Backend Guide