Celestial bodies¶

Source: AI/Tools/CelestialBodyTools.cs

Two tools for accessing the SPICE-backed ephemeris and intrinsic geophysical properties of celestial items.

GetEphemerisAsStateVectors¶

Get the state vectors (position and velocity) of a target observed from an observer in a given frame over a time range.

Parameter	Type	Description
`observerName`	`CelestialItemsEnum`	Observer (NAIF-keyed enum)
`targetName`	`CelestialItemsEnum`	Target
`frame`	`FramesEnum`	Output reference frame
`startTime`	ISO 8601 string	Window start (Time rules)
`endTime`	ISO 8601 string	Window end
`timeStep`	seconds, > 0	Sampling cadence
`aberrationCorrection`	`Aberration`	`None`, `LT`, `LT+S`, …

Returns a list of StateVector (position, velocity, epoch, center of motion, frame).

{
  "observerName": "SUN",
  "targetName": "EARTH",
  "frame": "ICRF",
  "startTime": "2024-06-21T00:00:00",
  "endTime": "2024-06-22T00:00:00",
  "timeStep": 3600,
  "aberrationCorrection": "None"
}

GetCelestialBodyProperties¶

Get the geophysical properties of a celestial body: NAIF IDs, name, tri-axial radii, GM, body-fixed frame, and zonal harmonics J2/J3/J4.

Parameter	Type	Description
`celestialBodyName`	`PlanetsMoonsEnum`	Body with an ellipsoid model

Returns a CelestialBody record with the body's intrinsic parameters.

{ "celestialBodyName": "EARTH" }