The true equator true equinox coordinate
system evaluated at the epoch of the object.
| 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. |