Spacecraft.Bstar Property

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Description

This property has been Deprecated. Please use Spacecraft.SGP4.Bstar instead.

 

A special "drag" term associated with the Norad SGP4/SDP4 propagators. It measured in units of 1/earth radii and is related to the Spacecraft's Cd. It is obtained by having FreeFlyer import the NORAD Two-Line Element (TLE) state vector. It is also computed by FreeFlyer when a conversion from Cartesian elements to Norad element is invoked.

 

B* is calculated as follows:

 

 

Where:

ρ0 Norad Atmospheric Density, 2.461e-5 kg/m2/RE

CD Coefficient of drag

A Spacecraft drag area in m2

RE Norad Earth Radius, 6378.135 km

m Spacecraft mass in kg

 

 

Timing Precision Mode

This page describes functionality in millisecond timing precision mode.

 

Attributes

Type:

number

Access:

read/write

Units:

er-1

Default Value:

0.0002

 

Syntax

myVariable1 = mySpacecraft1.Bstar;

 

mySpacecraft1.Bstar = myVariable1;

 

See also

Spacecraft Object

Spacecraft Propagation Guide

Coverage and Contact Analysis Guide