View Source SpaceDust.State.GeodeticState (Space Dust v0.3.0)

State in geodetic coordinates (latitude, longitude, altitude).

Uses WGS84 ellipsoid for Earth reference. This is the standard representation for ground-based observer locations.

  • Latitude: Geodetic latitude in degrees (-90 to +90, positive North)
  • Longitude: Geodetic longitude in degrees (-180 to +180, positive East)
  • Altitude: Height above WGS84 ellipsoid in kilometers

Summary

Types

t()

Functions

from_ecef(ecef_state)

Create geodetic state from an ECEF state. Uses iterative algorithm for accurate conversion.

local_sidereal_time(geodetic_state, epoch)

Get the local sidereal time at the observer's location. Returns LST in radians.

new(latitude, longitude, altitude)

Create a new geodetic state.

to_ecef(geodetic_state, epoch)

Convert geodetic coordinates to ECEF position.

to_eci(geodetic, epoch)

Convert geodetic state to ECI position at a given epoch.

Types

t()

@type t() :: %SpaceDust.State.GeodeticState{
  altitude: float(),
  latitude: float(),
  longitude: float()
}

Functions

from_ecef(ecef_state)

@spec from_ecef(SpaceDust.State.ECEFState.t()) :: t()

Create geodetic state from an ECEF state. Uses iterative algorithm for accurate conversion.

local_sidereal_time(geodetic_state, epoch)

@spec local_sidereal_time(t(), DateTime.t()) :: float()

Get the local sidereal time at the observer's location. Returns LST in radians.

new(latitude, longitude, altitude)

@spec new(float(), float(), float()) :: t()

Create a new geodetic state.

Parameters

  • latitude: Geodetic latitude in degrees (-90 to +90)
  • longitude: Geodetic longitude in degrees (-180 to +180)
  • altitude: Height above WGS84 ellipsoid in kilometers

Example 

iex> SpaceDust.State.GeodeticState.new(40.0, -105.0, 1.6)

to_ecef(geodetic_state, epoch)

@spec to_ecef(t(), DateTime.t()) :: SpaceDust.State.ECEFState.t()

Convert geodetic coordinates to ECEF position.

Returns an ECEF position vector {x, y, z} in kilometers. Velocity is set to zero (stationary observer).

to_eci(geodetic, epoch)

@spec to_eci(t(), DateTime.t()) :: SpaceDust.State.ECIState.t()

Convert geodetic state to ECI position at a given epoch.