Skip to content

IO Aerospace

Predefined Objects

Predefined Objects¶

The framework provides predefined constants for solar system bodies and reference frames to avoid recreating standard NAIF object mappings in application code.

SolarSystemObjects.PlanetsAndMoons¶

Planets¶

Constant	Description
`MERCURY`	Mercury (NAIF ID)
`VENUS`	Venus
`EARTH`	Earth (NAIF ID)
`EARTH_BODY`	Earth as `CelestialBody` instance
`MARS`	Mars
`JUPITER`	Jupiter
`SATURN`	Saturn
`URANUS`	Uranus
`NEPTUNE`	Neptune

Earth System¶

Constant	Description
`MOON`	Moon (NAIF ID)
`MOON_BODY`	Moon as `CelestialBody` instance

Mars System¶

Constant	Description
`PHOBOS`	Phobos
`DEIMOS`	Deimos

Outer Planet Moons¶

The module also provides NAIF IDs for the complete catalog of known moons:

Jupiter: IO, EUROPA, GANYMEDE, CALLISTO, AMALTHEA, HIMALIA, and 50+ additional moons
Saturn: MIMAS, ENCELADUS, TETHYS, DIONE, RHEA, TITAN, IAPETUS, PHOEBE, HYPERION, and 50+ additional moons
Uranus: ARIEL, UMBRIEL, TITANIA, OBERON, MIRANDA, and 20+ additional moons
Neptune: TRITON, NEREID, and additional moons

All constants are NaifObject instances. Create a CelestialBody from any of them:

var titan = new CelestialBody(PlanetsAndMoons.TITAN);

SolarSystemObjects.Barycenters¶

Constant	Description
`SOLAR_SYSTEM_BARYCENTER`	Solar system barycenter (NAIF 0)
`MERCURY_BARYCENTER`	Mercury system barycenter
`VENUS_BARYCENTER`	Venus system barycenter
`EARTH_BARYCENTER`	Earth-Moon barycenter
`MARS_BARYCENTER`	Mars system barycenter
`JUPITER_BARYCENTER`	Jupiter system barycenter
`SATURN_BARYCENTER`	Saturn system barycenter
`URANUS_BARYCENTER`	Uranus system barycenter
`NEPTUNE_BARYCENTER`	Neptune system barycenter
`PLUTO_BARYCENTER`	Pluto system barycenter

SolarSystemObjects.Stars¶

Constant	Description
`Sun`	Sun (NAIF 10)
`SUN_BODY`	Sun as `CelestialBody` / `Star` instance

Predefined Frames¶

Common Frames (`Frame`)¶

Constant	Description
`Frame.ICRF`	International Celestial Reference Frame
`Frame.TEME`	True Equator Mean Equinox (SGP4 output frame)
`Frame.ECLIPTIC_J2000`	Ecliptic plane at J2000 epoch
`Frame.ECLIPTIC_B1950`	Ecliptic plane at B1950 epoch
`Frame.GALACTIC_SYSTEM2`	Galactic coordinate system II
`Frame.B1950`	Mean equator and equinox of B1950
`Frame.FK4`	Fundamental Katalog 4 frame

Earth Orientation Frames (`Frames`) (Pro)¶

Pro

These frames are available from IO.Astrodynamics.Frames.Frames.

Constant	Description
`Frames.GCRF`	Geocentric realization of ICRS with IAU frame bias
`Frames.CIRS`	Celestial intermediate reference system (CIO-based precession-nutation)
`Frames.TIRS`	Terrestrial intermediate reference system (adds Earth rotation angle)

Example¶

var earth = PlanetsAndMoons.EARTH_BODY;
var moon = new CelestialBody(PlanetsAndMoons.MOON);

var state = moon.GetEphemeris(epoch, earth, Frame.ICRF, Aberration.None)
    .ToStateVector();

See Also¶