Missile: Classical Elements: ICRF

Earth's attitude expressed with respect to the ICRF frame.

Name Dimension Type Description
Time DateFormat Real Number Time.
Semi-major Axis DistanceUnit Real Number A measure of the size of the orbit. Orbits with eccentricity <1 are ellipses, with major and minor axes identifying the symmetry axes of the ellipse, the major axis being the longer one. The value is half the length of the major axis.
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.
RAAN LongitudeUnit Real Number The angle in the XY plane from the X axis to the ascending node, measured in a right-handed sense about the Z axis. in the equatorial plane. For equatorial orbits, the ascending node is defined to be directed along the positive X axis, and thus the value is 0.0. The Calc Object allows a choice of coordinate systems. The default is Earth Centered Inertial.
Arg of Perigee 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).
True Anomaly AngleUnit Real Number The angle from the periapsis vector, measured in the orbit plane in the direction of motion, to the position vector.
Mean Anomaly AngleUnit Real Number A measure of the time past periapsis passing, expressed as an angle.
Arg of Latitude AngleUnit Real Number The sum of the true anomaly and the argument of periapsis..
Apogee Altitude DistanceUnit Real Number The difference between the radius of apoapsis and the central body's equatorial radius.
Apogee Radius 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.
Perigee Altitude DistanceUnit Real Number The difference between the radius of periapsis and the central body's equatorial radius.
Perigee Radius DistanceUnit Real Number The magnitude of the periapsis vector. The periapsis vector locates the position in the orbit closest to the central body.
Mean Motion (Revs/Day) Unitless Real Number A measure of the osculating period of the orbit, expressed as an angular rate. The value is 2pi rad / orbit_period. Expressed as revolutions per day.
Lon Ascn Node LongitudeUnit 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.
Eccentric Anomaly AngleUnit Real Number An angle used for converting between true and mean anomaly. Has a geometrical definition as the angle between the line of apsides and a line running from the center of the ellipse to a point Q on a circle circumscribed about the ellipse. The point Q is a projection of the satellite along a line parallel to the minor axis of the ellipse.
Time Past AN TimeUnit Real Number The elapsed time since passing the last ascending node crossing based on assumed two-body motion..
Time Past Perigee TimeUnit Real Number The elapsed time since passing the last periapsis crossing based on assumed two-body motion..
Period TimeUnit Real Number The time to complete an entire cycle.
Longitude of Perigee LongitudeUnit Real Number The sum of the right ascension of the ascending node and the argument of periapsis.
Mean Longitude LongitudeUnit Real Number mean longitude is the sum: right_ascension_of_the_ascending_node + argument_of_periapse + mean_anomaly. A measure of the location within the orbit.

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