Spacecraft.CardinalPoints Method

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Description

Returns the times when the Spacecraft is at each of the cardinal points. The cardinal point calculations are based on the alpha angle, which is the angle between the Spacecraft's position and the target CelestialObject's position with respect to the Spacecraft's central body when both vectors are projected onto the Spacecraft's orbit plane. Note that the target CelestialObject is modeled as a point.

 

The cardinal points, as a function of the alpha angle, are defined as:

 

- Noon (alpha angle = 0)

- Dusk (alpha angle = 90)

- Midnight (alpha angle = 180)

- Dawn (alpha angle = 270)

 

The mathematical definition of the alpha angle is:

 

 

Below is a diagram depicting how the alpha angle is defined:

 

A visual representation of the Alpha angle.

A visual representation of the Alpha angle.

 

Timing Precision Mode

This page describes functionality in nanosecond timing precision mode.

 

Overload List

Signatures

Spacecraft.CardinalPoints()

Spacecraft.CardinalPoints(CelestialObject)

Spacecraft.CardinalPoints(TimeSpanArray, Array)

Spacecraft.CardinalPoints(CelestialObject, TimeSpanArray, Array)

 

See also

Spacecraft Object

Spacecraft.SpacecraftNoon

Spacecraft.SunTerminatorCrossingTimes

Spacecraft Propagation Guide

Coverage and Contact Analysis Guide