Data Provider Groups | Data Provider Elements

Mixed Spherical Elements

The position and velocity of the object, expressed in mixed spherical elements, as a function of time. The position is expressed using LLA elements, with respect to the vehicle's central body fixed coordinate system -- the requested coordinate system is immaterial. The velocity of the object is computed as observed from the requested coordinate system.

Available for these objects: LaunchVehicle, Missile, Satellite

Type: Time-varying data.

Availability: Reports | Graphs | Dynamic Displays | Strip Charts

Data Provider Groups

Data can be requested in a variety of coordinate systems, where the origin of the coordinate system is the object's central body. The available coordinate systems depend on the object's central body. Nominally, the systems Fixed, Inertial, J2000, TrueOfDate, and MeanOfDate are supported, although some central bodies (notably the Earth and Sun) have more.

The following lists the systems available for Earth.
NameDescription
ICRFInternational Celestial Reference Frame. The ICRF axes are defined as the inertial (i.e., kinematically non-rotating) axes associated with a general relativity frame centered at the solar system barycenter (often called the BCRF).
MeanOfDateThe mean equator mean equinox coordinate system evaluated at the requested time.
MeanOfEpochThe mean equator mean equinox coordinate system evaluated at the epoch of the object.
TrueOfDateThe true equator true equinox coordinate system evaluated at the requested time.
TrueOfEpochThe true equator true equinox coordinate system evaluated at the epoch of the object.
B1950The mean equator mean equinox coordinate system evaluated at the beginning of the Besselian year 1950 (31 December 1949 22:09:46.866 = JD 2433282.4234591).
TEMEOfEpochThe true equator mean equinox coordinate system evaluated at the epoch of the object.
TEMEOfDateThe true equator mean equinox coordinate system evaluated at the requested time.
AlignmentAtEpochThe nonrotating coordinate system coincident with the Fixed system evaluated at the object's coordinate reference epoch.
J2000The mean equator mean equinox coordinate system evaluated at the J2000.0 epoch (2000 January 1.5 TDB = JD 2451545.0 TDB).

Data Provider Elements

NameDimensionTypeDescription
TimeDateReal Number or TextTime.
Detic LatAngleReal Number or TextThe detic latitude (i.e., angle between the detic subpoint's surface normal vector and the XY plane.).
Detic LonLongitudeReal Number or TextThe detic longitude (i.e., angle from the X-axis locating the projection of the detic subpoint's surface normal vector onto the XY plane.) Longitude increases in the direction found using the right-hand rule about the Z-axis.
Detic AltDistanceReal NumberThe altitude value (i.e., magnitude of the relative position vector between the object and its detic subpoint).
Horiz Flt Path AngAngleReal Number or TextThe angle between the position vector and the plane whose normal is the velocity vector.
Flt Path AziLongitudeReal Number or TextThe angle, measured in the plane perpendicular to the position vector, between the local north direction and the projection of the velocity vector onto that plane, measured as positive moving toward local east.
VelocityRateReal NumberThe magnitude of the velocity vector, as observed in the object's central body fixed coordinate system.