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SuperNOVAS v1.5
The NOVAS C library, made better
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Calculate approximate positions and velocities for the major planets, Sun, Moon, Earth-Moon Barycenter (EMB), and the Solar-system Barycenter (SSB), mainly by using Keplerian orbital elements. More...
Functions | |
int | novas_approx_heliocentric (enum novas_planet id, double jd_tdb, double *restrict pos, double *restrict vel) |
Returns the approximate geometric heliocentric orbital positions and velocities for the major planets, Sun, or Earth-Moon Barycenter (EMB). | |
int | novas_approx_sky_pos (enum novas_planet id, const novas_frame *restrict frame, enum novas_reference_system sys, sky_pos *restrict out) |
Calculates an approximate apparent location on sky for a major planet, Sun, Moon, Earth-Moon Barycenter (EMB) – typically to arcmin level accuracy – using Keplerian orbital elements. | |
int | novas_make_moon_orbit (double jd_tdb, novas_orbital *restrict orbit) |
Gets the current orbital elements for the Moon relative to the geocenter for the specified epoch of observation. | |
int | novas_make_planet_orbit (enum novas_planet id, double jd_tdb, novas_orbital *restrict orbit) |
Get approximate current heliocentric orbital elements for the major planets. | |
double | novas_moon_phase (double jd_tdb) |
Calculates the Moon's phase at a given time. | |
double | novas_next_moon_phase (double phase, double jd_tdb) |
Calculates the date / time at which the Moon will reach the specified phase next, after the specified time. | |
double | planet_lon (double t, enum novas_planet planet) |
Returns the planetary longitude, for Mercury through Neptune, w.r.t. | |
Calculate approximate positions and velocities for the major planets, Sun, Moon, Earth-Moon Barycenter (EMB), and the Solar-system Barycenter (SSB), mainly by using Keplerian orbital elements.
For more precise planet positions, you should use SuperNOVAS with a planetary ephemeris provider, as as the CALCEPH or CSPICE plugin interface modules, or custom ephemeris provider functions.
double planet_lon | ( | double | t, |
enum novas_planet | planet ) |
Returns the planetary longitude, for Mercury through Neptune, w.r.t.
mean dynamical ecliptic and equinox of J2000, with high order terms omitted (Simon et al. 1994, 5.8.1-5.8.8).
REFERENCES:
t | [cy] Julian centuries since J2000 |
planet | Novas planet id, e.g. NOVAS_MARS. |
planet
id is out of range.References NOVAS_NEPTUNE, and TWOPI.