Satellite: Astrogator Values: Keplerian Elems

Calc Objects for the ephemeris of the object, expressed in keplerian (i.e., instantaneous two-body) elements. Each Calc Object allows a choice of element type (Osculating elements, Kozai-Izsak Mean elements, Brouwer-Lyddane Mean elements using only short period terms, and Brouwer-Lyddane Mean elements using both short and long period terms). The default is osculating.

Name Dimension Type Description
Time DateFormat Real Number Time.
Altitude_Of_Apoapsis DistanceUnit Real Number The difference between the radius of apoapsis and the central body's equatorial radius. The Calc Object allows a choice of a central body. The default is Earth.
Altitude_Of_Periapsis DistanceUnit Real Number The difference between the radius of apoapsis and the central body's equatorial radius. The Calc Object allows a choice of a central body. The default is Earth.
Argument_of_Latitude AngleUnit Real Number The sum of the argument of periapsis and true anomaly. The Calc Object allows a choice of coordinate systems. The default is Earth Centered Inertial.
Argument_of_Periapsis AngleUnit Real Number The angle from the ascending node to the periapsis vector measured in the orbit plane in the direction of the object's motion. The periapsis vector locates the closest point of the orbit. For a circular orbit, the value is defined to be zero (i.e., periapsis at the ascending node). The Calc Object allows a choice of coordinate systems. The default is Earth Centered Inertial.
Eccentric_Anomaly AngleUnit Real Number Not defined for this class of object.
Eccentricity Unitless Real Number A measure of the shape of the orbit. Values <1 indicate an ellipse (where zero is a circular orbit) and values >1 indicate a hyperbola.
Inclination AngleUnit Real Number The angle between the orbit plane and the XY plane of the coordinate system.
Longitude_Of_Ascending_Node AngleUnit Real Number A measure of the right ascension of the ascending node, made in the Fixed frame. The value is the detic longitude of the orbit's ascending node. The ascending node crossing is assumed to be at, or prior to, the current position in the orbit in the same nodal revolution. The Calc Object allows a choice of a central body. The default is Earth.
MeanAnomaly AngleUnit Real Number A measure of the time past periapsis passing, expressed as an angle. The Calc Object allows a choice of a central body. The default is Earth.
Mean_Motion AngleRateUnit Real Number Not defined for this class of object.
Orbit_Period TimeUnit Real Number Time required for a complete revolution as computed from osculating semi-major axis length. The Calc Object allows a choice of a central body. The default is Earth.
RAAN AngleUnit Real Number Not defined for this class of object.
Radius_Of_Apoapsis DistanceUnit Real Number The magnitude of the apoapsis vector. The apoapsis vector (defined only when the eccentricity is <1) locates the position in the orbit furthest from the central body. The Calc Object allows a choice of a central body. The default is Earth.
Radius_Of_Periapsis DistanceUnit Real Number The magnitude of the periapsis vector. The periapsis vector locates the position in the orbit closest to the central body. The Calc Object allows a choice of a central body. The default is Earth.
Semimajor_Axis DistanceUnit Real Number Not defined for this class of object.
Time_Past_Asc_Node TimeUnit Real Number The elapsed time since passing the last ascending node crossing based on assumed two-body motion.. The Calc Object allows a choice of coordinate systems. The default is Earth Centered Inertial.
Time_Past_Periapsis TimeUnit Real Number The elapsed time since passing the last periapsis crossing based on assumed two-body motion.. The Calc Object allows a choice of a central body. The default is Earth.
True_Anomaly AngleUnit Real Number Not defined for this class of object.

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