Ryan Malloy
3915d1784f
An existing product called PG Orbit (a mobile PostgreSQL client) creates a naming conflict. pg_orrery — a database orrery built from Keplerian parameters and SQL instead of brass gears. Build system: control file, Makefile, Dockerfile, docker init script. C source: GUC prefix, PG_FUNCTION_INFO_V1 symbol, header guards, ereport prefixes, comments across ~30 files including vendored SGP4. SQL: all 5 install/migration scripts, function name pg_orrery_ephemeris_info. Tests: 9 SQL suites, 8 expected outputs, standalone DE reader test. Documentation: CLAUDE.md, README.md, DESIGN.md, Starlight site infra, 36 MDX pages, OG renderer, logo SVG, docker-compose, agent threads. All 13 regression suites pass. Docs site builds (37 pages).
48 lines
1.5 KiB
C
48 lines
1.5 KiB
C
/*
|
|
* sidereal_time.h -- Greenwich sidereal time (mean and apparent)
|
|
*
|
|
* Clean-room implementation from published standards:
|
|
* IERS Conventions (2010), IERS Technical Note 36, Ch. 5.
|
|
* Capitaine, Guinot & McCarthy (2000), "Definition of the
|
|
* Celestial Ephemeris Origin and of UT1 in the International
|
|
* Celestial Reference Frame", A&A 355, 398-405.
|
|
*
|
|
* No PostgreSQL dependencies -- pure math, suitable for standalone use.
|
|
*/
|
|
|
|
#ifndef PG_ORRERY_SIDEREAL_TIME_H
|
|
#define PG_ORRERY_SIDEREAL_TIME_H
|
|
|
|
/*
|
|
* get_mean_sidereal_time -- Greenwich Mean Sidereal Time
|
|
*
|
|
* Computes GMST using the classical polynomial in UT1,
|
|
* consistent with IAU 2006 precession.
|
|
*
|
|
* JD = Julian Date (UT1 timescale)
|
|
* JDE = Julian Ephemeris Date (TDB/TT timescale)
|
|
*
|
|
* For pg_orrery Phase 2, JD and JDE are treated as identical
|
|
* (delta-T correction not yet applied; the difference is <1s
|
|
* for recent epochs).
|
|
*
|
|
* Returns GMST in radians, normalized to [0, 2*pi).
|
|
*/
|
|
double get_mean_sidereal_time(double JD, double JDE);
|
|
|
|
/*
|
|
* get_apparent_sidereal_time -- Greenwich Apparent Sidereal Time
|
|
*
|
|
* GAST = GMST + equation of the equinoxes.
|
|
*
|
|
* The equation of the equinoxes accounts for nutation:
|
|
* EqEq = delta_psi * cos(epsilon_A)
|
|
* where delta_psi is nutation in longitude and epsilon_A is
|
|
* the mean obliquity, both from precession.h.
|
|
*
|
|
* Returns GAST in radians, normalized to [0, 2*pi).
|
|
*/
|
|
double get_apparent_sidereal_time(double JD, double JDE);
|
|
|
|
#endif /* PG_ORRERY_SIDEREAL_TIME_H */
|