AdvCAT: Event Ephemeris

Reports ephemeris and other related information as a function of time for each close approach event.

Type: Time-varying data. Intended to be used only with elements from this same data provider.

Availability: Reports

Name Dimension Type Description
Approach Angle AngleUnit Real Number The angle between the inertial velocity of the primary object and the inertial velocity of the secondary object at the given time
Ellipsoid Norm wrt Primary Unitless Real Number or Text A measure of the "distance" between the primary and secondary object, using the primary object's ellipsoid size as a norm, at the given time. If the primary ellipsoid size were to be scaled uniformly by this value, then the ellipsoid would just touch the secondary. The value is set to "Undefined" if an error occurs computing the norm.
Ellipsoid Norm wrt Secondary Unitless Real Number or Text A measure of the "distance" between the primary and secondary object, using the secondary object's ellipsoid size as a norm, at the given time. If the secondary ellipsoid size were to be scaled uniformly by this value, then the ellipsoid would just touch the primary. The value is set to "Undefined" if an error occurs computing the norm.
Primary Alt DistanceUnit Real Number The primary object's detic altitude at the given time.
Primary Concurrent Events Unitless Integer The number of secondaries experiencing a close approach event with the primary at this time.
Primary Ellipsoid - CrossTrack DistanceUnit Real Number The length of the primary object's ellipsoid at the given time in the cross-track direction. The cross-track direction lies along the object's orbit normal.
Primary Ellipsoid - Max DistanceUnit Real Number The length of the longest symmetry axis of the primary object's ellipsoid at the given time.
Secondary Alt DistanceUnit Real Number The secondary object's detic altitude at the given time.
Primary Ellipsoid - Middle DistanceUnit Real Number The length of the intermediate symmetry axis of the primary object's ellipsoid at the given time.
Primary Ellipsoid - Min DistanceUnit Real Number The length of the shortest symmetry axis of the primary object's ellipsoid at the given time.
Range wrt Primary - CrossTrack DistanceUnit Real Number The component of the relative position vector (i.e., secondary position vector minus primary position vector) in the primary object's cross-track direction at the given time. The cross-track direction lies along the object's orbit normal.
Primary Ellipsoid - Normal DistanceUnit Real Number The length of the primary object's ellipsoid at the given time in the normal direction. The normal direction completes a triad involving the tangential and cross-track directions and is akin to the radial direction.
Secondary Lat LatitudeUnit Real Number The secondary object's detic latitude at the given time.
Primary Ellipsoid - Tangential DistanceUnit Real Number The length of the primary object's ellipsoid at the given time in the tangential direction. The tangential direction lies along the object's inertial velocity.
Secondary Lon LongitudeUnit Real Number The secondary object's detic longitude at the given time.
Secondary Ellipsoid - CrossTrack DistanceUnit Real Number The length of the secondary object's ellipsoid at the given time in the cross-track direction. The cross-track direction lies along the object's orbit normal.
Range wrt Primary - Tangential DistanceUnit Real Number The component of the relative position vector (i.e., secondary position vector minus primary position vector) in the primary object's tangential direction at the given time. The tangential direction lies along the object's inertial velocity.
Range wrt Primary - Normal DistanceUnit Real Number The component of the relative position vector (i.e., secondary position vector minus primary position vector) in the primary object's normal direction at the given time. The normal direction completes a triad involving the tangential and cross-track directions and is akin to the radial direction.
Secondary Ellipsoid - Max DistanceUnit Real Number The length of the longest symmetry axis of the secondary object's ellipsoid at the given time.
Secondary x DistanceUnit Real Number The X component of the inertial position vector of the secondary object at the given time.
Secondary Ellipsoid - Tangential DistanceUnit Real Number The length of the secondary object's ellipsoid at the given time in the tangential direction. The tangential direction lies along the object's inertial velocity.
Secondary y DistanceUnit Real Number The Y component of the inertial position vector of the secondary object at the given time.
Secondary: Time Since Epoch TimeUnit Real Number The difference between the given time time and the secondary object's epoch.
Primary Lat LatitudeUnit Real Number The primary object's detic latitude at the given time.
Secondary Ellipsoid - Normal DistanceUnit Real Number The length of the secondary object's ellipsoid at the given time in the normal direction. The normal direction completes a triad involving the tangential and cross-track directions and is akin to the radial direction.
Secondary z DistanceUnit Real Number The Z component of the inertial position vector of the secondary object at the given time.
Secondary vx Rate Real Number The X component of the inertial velocity vector of the secondary object at the given time.
Secondary Ellipsoid - Middle DistanceUnit Real Number The length of the intermediate symmetry axis of the secondary object's ellipsoid at the given time.
Secondary vy Rate Real Number The Y component of the inertial velocity vector of the secondary object at the given time.
Range wrt Primary - Radial DistanceUnit Real Number The component of the relative position vector (i.e., secondary position vector minus primary position vector) in the primary object's radial direction at the given time.
Secondary vz Rate Real Number The Z component of the inertial velocity vector of the secondary object at the given time.
Secondary Ellipsoid - Min DistanceUnit Real Number The length of the shortest symmetry axis of the secondary object's ellipsoid at the given time.
Range wrt Primary - InTrack DistanceUnit Real Number The component of the relative position vector (i.e., secondary position vector minus primary position vector) in the primary object's in-track direction at the given time. The in-track direction completes a triad involving the radial and cross-track directions.
Primary Lon LongitudeUnit Real Number The primary object's detic longitude at the given time.
Primary NumberID Unitless Text The number identifier of the primary object involved in the close approach event. If the object has no number identifier, then the value will be "Not Avail".
Secondary Pitch AngleUnit Real Number The pitch angle for the secondary object's ellipsoid at the given time. The pitch angle locates the major axis of the ellipsoid from the plane whose normal is the cross-track direction.
Primary Pitch AngleUnit Real Number The pitch angle for the primary object's ellipsoid at the given time. The pitch angle locates the major axis of the ellipsoid from the plane whose normal is the cross-track direction.
Secondary Roll AngleUnit Real Number The roll angle for the secondary object's ellipsoid at the given time. The roll angle locates the minor axis of the ellipsoid as a rotation about the major axis, with zero being aligned with the cross-track direction.
Secondary Yaw AngleUnit Real Number The yaw angle for the secondary object's ellipsoid at the given time. The yaw angle locates from the tangential direction the projection of the major axis of the ellipsoid onto the plane whose normal is the cross-track direction.
Range wrt Secondary - CrossTrack DistanceUnit Real Number The component of the relative position vector (i.e., primary position vector minus secondary position vector) in the secondary object's cross-track direction at the given time. The cross-track direction lies along the object's orbit normal.
Primary Roll AngleUnit Real Number The roll angle for the primary object's ellipsoid at the given time. The roll angle locates the minor axis of the ellipsoid as a rotation about the major axis, with zero being aligned with the cross-track direction.
Primary SSC Unitless Integer The SSC number of the primary object involved in the close approach event.
Range wrt Secondary - Tangential DistanceUnit Real Number The component of the relative position vector (i.e., primary position vector minus secondary position vector) in the secondary object's tangential direction at the given time. The tangential direction lies along the object's inertial velocity.
Range wrt Secondary - Normal DistanceUnit Real Number The component of the relative position vector (i.e., primary position vector minus secondary position vector) in the secondary object's normal direction at the given time. The normal direction completes a triad involving the tangential and cross-track directions and is akin to the radial direction.
Primary StringID Unitless Text The string identifier of the primary object involved in the close approach event. If the object has no string identifier, then the value will be "Not Avail".
Range wrt Secondary - Radial DistanceUnit Real Number The component of the relative position vector (i.e., primary position vector minus secondary position vector) in the secondary object's radial direction at the given time.
Range wrt Secondary - InTrack DistanceUnit Real Number The component of the relative position vector (i.e., primary position vector minus secondary position vector) in the secondary object's in-track direction at the given time. The in-track direction completes a triad involving the radial and cross-track directions.
Primary vx Rate Real Number The X component of the inertial velocity vector of the primary object at the given time.
Primary vy Rate Real Number The Y component of the inertial velocity vector of the primary object at the given time.
Primary vz Rate Real Number The Z component of the inertial velocity vector of the primary object at the given time.
Primary x DistanceUnit Real Number The X component of the inertial position vector of the primary object at the given time.
Primary y DistanceUnit Real Number The Y component of the inertial position vector of the primary object at the given time.
Primary Yaw AngleUnit Real Number The yaw angle for the primary object's ellipsoid at the given time. The yaw angle locates from the tangential direction the projection of the major axis of the ellipsoid onto the plane whose normal is the cross-track direction.
Primary z DistanceUnit Real Number The Z component of the inertial position vector of the primary object at the given time.
Primary: Time Since Epoch TimeUnit Real Number The difference between the given time and the primary object's epoch.
Range Sigma Unitless Real Number The value of the range between the objects measured at TCA, expressed in terms of sigma (i.e., the scale factor by which the combined covariance ellipsoid would need to be scaled to just touch the range vector).
Range Uncertainty DistanceUnit Real Number The uncertainty in the range at the given time. The uncertainty is computed by treating the ellipsoid size and orientation as a measure of the position covariance for each object. The relative position covariance is then computed and projected onto the line of sight direction between the two objects to compute the value.
Velocity wrt Primary - CrossTrack Rate Real Number The component of the relative inertial velocity vector (i.e., secondary inertial velocity vector minus primary inertial velocity vector) in the primary object's cross-track direction at the given time. The cross-track direction lies along the object's orbit normal.
Range DistanceUnit Real Number The range (i.e., distance between the primary and secondary object) at the given time.
Relative Velocity Rate Real Number The magnitude of the difference in the inertial velocities of the primary and secondary objects at the given time.
Velocity wrt Primary - Tangential Rate Real Number The component of the relative inertial velocity vector (i.e., secondary inertial velocity vector minus primary inertial velocity vector) in the primary object's tangential direction at the given time. The tangential direction lies along the object's inertial velocity.
Velocity wrt Primary - Normal Rate Real Number The component of the relative inertial velocity vector (i.e., secondary inertial velocity vector minus primary inertial velocity vector) in the primary object's normal direction at the given time. The normal direction completes a triad involving the tangential and cross-track directions and is akin to the radial direction.
Secondary NumberID Unitless Text The number identifier of the secondary object involved in the close approach event. If the object has no number identifier, then the value will be "Not Avail".
Velocity wrt Primary - Radial Rate Real Number The component of the relative inertial velocity vector (i.e., secondary inertial velocity vector minus primary inertial velocity vector) in the primary object's radial direction at the given time.
Velocity wrt Primary - InTrack Rate Real Number The component of the relative inertial velocity vector (i.e., secondary inertial velocity vector minus primary inertial velocity vector) in the primary object's in-track direction at the given time. The in-track direction completes a triad involving the radial and cross-track directions.
Secondary SSC Unitless Integer The SSC number of the secondary object involved in the close approach event.
Secondary StringID Unitless Text The string identifier of the secondary object involved in the close approach event. If the object has no string identifier, then the value will be "Not Avail".
Velocity wrt Secondary - CrossTrack Rate Real Number The component of the relative inertial velocity vector (i.e., primary inertial velocity vector minus secondary inertial velocity vector) in the secondary object's cross-track direction at the given time. The cross-track direction lies along the object's orbit normal.
Separation DistanceUnit Real Number or Text The separation distance between the primary and secondary threat volumes at the given time. If the ellipsoids intersect, then the value will be "Intersect".
Time DateFormat Real Number Time.
Velocity wrt Secondary - Tangential Rate Real Number The component of the relative inertial velocity vector (i.e., primary inertial velocity vector minus secondary inertial velocity vector) in the secondary object's tangential direction at the given time. The tangential direction lies along the object's inertial velocity.
Velocity wrt Secondary - Normal Rate Real Number The component of the relative inertial velocity vector (i.e., primary inertial velocity vector minus secondary inertial velocity vector) in the secondary object's normal direction at the given time. The normal direction completes a triad involving the tangential and cross-track directions and is akin to the radial direction.
Velocity wrt Secondary - InTrack Rate Real Number The component of the relative inertial velocity vector (i.e., primary inertial velocity vector minus secondary inertial velocity vector) in the secondary object's in-track direction at the given time. The in-track direction completes a triad involving the radial and cross-track directions.
Velocity wrt Secondary - Radial Rate Real Number The component of the relative inertial velocity vector (i.e., primary inertial velocity vector minus secondary inertial velocity vector) in the secondary object's radial direction at the given time.

STK Programming Interface 11.0.1