Satellite: Pos Vel Rotated Covariance

Provides data about position/velocity covariance matrix relative to selected set of axes. The covariance is transformed into the requested reference frame using a 6x6 transformation matrix consisting of two 3x3 coordinate transformation matrices along the diagonal and the skew-symmetric 3x3 matrix representing the angular velocity between the axes in the lower left. The result of this transformation is that the original covariance is re-expressed relative to the new axes including the effects of the rotation of the axes. The resultant covariance matrix represents the uncertainty of the position/velocity expressed in the new axes. The covariance information is reported in sigma-correlation form. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position/velocity covariance to be defined for the object. Note: This data provider does not support interpolation of the position/velocity covariance matrices. Output is limited to the times of the stored ephemeris points.

Type: Time-varying data

Availability: Reports | Graphs

Name Description
Body The object Body axes.
ICR Intrack Crosstrack Radial. The Z axis is outward along the radial, the Y axis is in the direction of the cross product of the position and inertial velocity and X axis is in the direction of motion and constructed as Y x Z.
ICR(CBF) Intrack Crosstrack Radial using the velocity as measured in the central body fixed frame. The Z axis is outward along the radial, the Y axis is in the direction of the cross product of the position and velocity measured in the central body fixed frame and X axis is in the direction of motion and constructed as Y x Z.
ICRF International Celestial Reference Frame. The ICRF is the best realization of an inertial frame constructed to date, and thus represents an improvement upon the theory behind the J2000 frame. While the ICRF and J2000 frames themselves are very close, they are not identical; moreover, the J2000 frame rotates (very slowly) over time with respect to the ICRF frame.
J2000 Mean Equator and Mean Equinox of the Earth at the J2000 epoch (JD 2451545.0 TDB which is 1 Jan 2000 12:00:00.000 TDB). The J2000 axes were considered the best realized inertial axes until the development of the ICRF.
LVLH Local Vertical Local Horizontal, also known as the Gauss frame and the RIC frame. The X axis is outward along the radial (local vertical), the Z axis is in the direction of the cross product of the position and velocity as measured in the central body inertial frame and Y axis is in the direction of motion and constructed as Z x X.
LVLH(CBF) Local Vertical Local Horizontal using the velocity as measured in the central body fixed frame. The X axis is outward along the radial (local vertical), the Z axis is in the direction of the cross product of the position and velocity as measured in the central body fixed frame and Y axis is in the direction of motion and constructed as Z x X.
LVLH(Earth) Local Vertical Local Horizontal based on the position and velocity measured in an Earth centered inertial reference frame. The X axis is outward along the radial (local vertical), the Z axis is in the direction of the cross product of the position and velocity as measured in the central body inertial frame and Y axis is in the direction of motion and constructed as Z x X.
Model The base axes defined in the 3D model associated with the object.
NorthEastDown Reports data about position covariance matrix including orientation of its principal axes relative to the NorthEastDown axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
NorthWestUp Reports data about position covariance matrix including orientation of its principal axes relative to the NorthWestUp axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
PositionCovPrincipal Reports data about position covariance matrix including orientation of its principal axes relative to the PositionCovPrincipal axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
Principal The principal axes of the inertia tensor.
RIC Radial Intrack Crosstrack. The X axis is outward along the radial, the Z axis is in the direction of the cross product of the position and inertial velocity and Y axis is in the direction of motion and constructed as Z x X.
RIC(CBF) Radial Intrack Crosstrack using the velocity as measured in the central body fixed frame. The X axis is outward along the radial, the Z axis is in the direction of the cross product of the position and velocity as measured in the central body fixed frame and Y axis is in the direction of motion and constructed as Z x X.
RadialCentric The Z axis is outward along the radial. The Y axis (East) is defined as the cross product of the central body fixed Z axis and the radial direction. The X axis is constructed as Y x Z. Similar to topocentric except that the radial direction is used instead of a direction normal to the central body surface.
SEET_GeocentricSolarMagnetic Geocentric Solar Magnetic: The X-axis aligned with the Earth-Sun line and the Z-axis constrained toward the magnetic north pole.
SEET_Geomagnetic Geomagnetic frame. The Z axis aligns with the magnetic north pole and the negative X axis is constrained toward the Earth Fixed Z axis.
SEET_SolarMagnetic Solar Magnetic frame. The Z axis aligns with the magnetic north pole and the X axis is constrained toward sun direction (as viewed from the earth).
TopoCentric Can be described as South East Up. The Z axis is outward along the detic surface normal away from the center of the central body (Up). The Y axis (East) is defined as the cross product of the central body fixed Z axis and the up direction. The X axis (South) is constructed as Y x Z.
TrueOfOrbitEpoch True equator and true equinox of the Earth at the orbit epoch. The orbit epoch is taken from the initial conditions of the satellite when possible, otherwise it is taken to be the time of the first ephemeris point.
VNC Reports data about position covariance matrix including orientation of its principal axes relative to the VNC axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
VNC(CBF) Reports data about position covariance matrix including orientation of its principal axes relative to the VNC(CBF) axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
VNC(Earth) Reports data about position covariance matrix including orientation of its principal axes relative to the VNC(Earth) axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
VNC(Mars) Reports data about position covariance matrix including orientation of its principal axes relative to the VNC(Mars) axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
VNC(Moon) Reports data about position covariance matrix including orientation of its principal axes relative to the VNC(Moon) axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
VNC(Sun) Reports data about position covariance matrix including orientation of its principal axes relative to the VNC(Sun) axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
VNC(Venus) Reports data about position covariance matrix including orientation of its principal axes relative to the VNC(Venus) axes and dimensions of the associated sigma scaled equal probability density ellipsoid. Any set of axes defined in the Vector Geometry Tool is available for use, including user defined sets. The data requires position covariance to be defined for the object.
VVLH Vehicle Vertical Local Horizontal. The Z axis is inward along the radial, the Y axis is in the direction of the cross product of the velocity as measured in the central body inertial frame and the position and Y axis is in the direction of motion and constructed as Y x Z.
VVLH(CBF) Vehicle Vertical Local Horizontal using the velocity as measured in the central body fixed frame. The Z axis is inward along the radial, the Y axis is in the direction of the cross product of the velocity as measured in the central body fixed frame and the position and Y axis is in the direction of motion and constructed as Y x Z.
VVLH(Earth) Vehicle Vertical Local Horizontal using position and velocity measured in an Earth centered inertial reference frame. The Z axis is inward along the radial, the Y axis is in the direction of the cross product of the velocity as measured in the central body inertial frame and the position and Y axis is in the direction of motion and constructed as Y x Z.
Earth Fixed The reference frame fixed to the surface of the Earth.

STK Programming Interface 11.0.1