Spacecraft.CloseApproachRange Method

Top 

Description

Returns a sequential listing of events related to the proximity of two objects. It provides the entry time and exit time of one object moving within the user specified range of another object, as well as the time and range of closest approach, and the time and range of greatest separation. The times and ranges are computed through one of two user-selectable formulations of the Alfano Negron Close Approach Software (ANCAS) interpolation algorithms.

 

Note that the ANCAS algorithms rely on crossing a range threshold in order to kick off the algorithm, so if two objects are always within the threshold or outside the threshold the no events will be reported. The ANCAS algorithms are designed to work well for high-relative velocity conjunctions and the results won't be as accurate for low-relative velocity conjunctions. For more information on the ANCAS algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

 

Timing Precision Mode

This page describes functionality in millisecond timing precision mode. Millisecond timing precision mode is deprecated and will be removed in a future release. We recommend that you migrate your Mission Plans to nanosecond timing precision mode.

Click here to see the documentation for this object in nanosecond timing precision mode.

 

Overload List

Signatures

Return Value

Description

Spacecraft.CloseApproachRange(Variable rangeLimit, GroundStation rangingStation)

String

Returns a sequential listing of events related to the proximity of the calling Spacecraft and the argument rangingStation using ANCAS 1 interpolation method. This method uses the position and velocity states from three data points to create a quintic polynomial approximating the range between the two objects over time.

 

For more information on the ANCAS algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

Spacecraft.CloseApproachRange(Variable rangeLimit, Spacecraft rangingSpacecraft)

String

Returns a sequential listing of events related to the proximity of the calling Spacecraft and the argument rangingSpacecraft using ANCAS 1 interpolation method. This method uses the position and velocity states from three data points to create a quintic polynomial approximating the range between the two objects over time.

 

For more information on the ANCAS algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

Spacecraft.CloseApproachRange(Variable rangeLimit, GroundStation rangingStation, Variable Algorithm)

String

Returns a sequential listing of events related to the proximity of the calling Spacecraft and the argument rangingStation using the specified Algorithm.

 

For more information on the ANCAS algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

Spacecraft.CloseApproachRange(Variable rangeLimit, Spacecraft rangingSpacecraft, Variable Algorithm)

String

Returns a sequential listing of events related to the proximity of the calling Spacecraft and the argument rangingSpacecraft using the specified Algorithm.

 

For more information on the Alfano/Negron Close Approach Software (ANCAS) algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

Spacecraft.CloseApproachRange(Variable rangeLimit, GroundStation rangingStation, Array EventTime, Array EventType, Array EventRange)

Variable

Returns a sequential listing of events related to the proximity of the calling Spacecraft and the argument rangingStation using ANCAS 1 interpolation method. This method uses the position and velocity states from three data points to create a quintic polynomial approximating the range between the two objects over time.

 

For more information on the ANCAS algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

Spacecraft.CloseApproachRange(Variable rangeLimit, Spacecraft rangingSpacecraft, Array EventTime, Array EventType, Array EventRange)

Variable

Returns a sequential listing of events related to the proximity of the calling Spacecraft and the argument rangingSpacecraft using ANCAS 1 interpolation method. This method uses the position and velocity states from three data points to create a quintic polynomial approximating the range between the two objects over time.

 

For more information on the ANCAS algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

Spacecraft.CloseApproachRange(Variable rangeLimit, GroundStation rangingStation, Variable Algorithm, Array EventTime, Array EventType, Array EventRange)

Variable

Returns a sequential listing of events related to the proximity of the calling Spacecraft and the argument rangingStation using the specified Algorithm.

 

For more information on the ANCAS algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

Spacecraft.CloseApproachRange(Variable rangeLimit, Spacecraft rangingSpacecraft, Variable Algorithm, Array EventTime, Array EventType, Array EventRange)

Variable

Returns a sequential listing of events related to the proximity of the calling Spacecraft and the argument rangingSpacecraft using the specified Algorithm.

 

For more information on the ANCAS algorithms, please refer to: Alfano, Salvatore. Determining Satellite Close Approaches, Part II. Journal of the Astronautical Sciences 42.2. Apr-Jun 1994, 143-152.

 

 

See also

Spacecraft Object

Spacecraft Propagation Guide

Coverage and Contact Analysis Guide