Set parameters for lifetime calculations
SetLifetime <SatObjectPath> {LifeOption} <Value>
The SetLifetime command allows you to set the parameters for lifetime calculations. User inputs include the satellite's physical characteristics as well as solar flux and planetary geomagnetic index information.
Use the Lifetime command to compute the Lifetime of a satellite.
Note: The SetLifetime command is only available for Satellites on Earth.
Valid values for {LifeOption} and <Value> can be:
| {LifeOption} <Value> | Description |
|---|---|
| DragCoeff <Value> | Specify the satellite's drag coefficient. <Value> is a unitless real number between 0.0 and 100.0. |
| ReflectCoeff <Value> | Specify the satellite's reflection coefficient, used in solar radiation pressure calculations. <Value> is a unitless real number between -1000.0 and 1000.0. |
| DragArea <Value> | Specify the mean cross-sectional area of the satellite perpendicular to its direction of travel. <Value> is a real number greater or equal to 0.0, entered in Meters squared |
| SunArea <Value> | Specify the satellite's mean area projected perpendicular to the Sun's direction. <Value> is a real number greater or equal to 0.0, entered in Meters squared |
| Mass <Mass> | <Mass> is greater than 0.0 and entered in Scenario Mass units. |
| LimitType {OrbitCount | Duration | All} | Limit lifetime computations by orbit count, duration or both. |
| OrbitLimit <Value> | Specify the maximum number of orbits that will be analyzed before the Lifetime tool stops processing. <Value> is a unitless integer greater or equal to 1. |
| DurationLimit <Value> | Specify the maximum number of days that will be analyzed before the Lifetime tool stops processing. <Value> is a unitless real number greater or equal to 0.0. |
| OrbPerCalc <Value> | Specify the number of orbits per calculation. The fewer orbits per calculation the more precise the lifetime estimate will be. The higher the number of orbits per calculation, the less precise the lifetime estimate will be, but calculations are completed much faster. <Value> is a unitless integer between 1 and 100. |
| GaussianQuad <Value> | <Value> is a unitless integer between 1 and 100. |
| DecayAltitude <Distance> | Specify the altitude at which the satellite's orbit is determined to be decayed. <Distance> is a real number, between 0.0 and 1000000.0 meters, entered in Scenario distance units. |
| SolarFluxFile "<FilePath>" | Specify a Solar Flux ASCII text file that is formatted for compatibility with STK and ends in a .dat extension, for example SolFlx_CSSI.dat. |
| FluxSigmaLevel <Level> | <Level> is the sigma level of F10 specified as a real number, between -5.0 and 5.0. This option only affects computations when a CSSI predict file is used as the source of solar flux information. |
| 2ndOrder {On | Off} | If On, a second-order correction is included in the Earth oblateness calculation. |
| Rotate {On | Off} | If On, the west-to-east winds induced by atmospheric rotation are included in the perturbations to the orbit. |
| Graphics {On | Off} | If On, the satellite's final orbit displays in the 2D Graphics window. |
| DensityModel "<ModelName>" | Valid values for "<ModelName>" are "1976 Standard", "CIRA 1972", "Harris-Priester", "Jacchia 1970", "Jacchia 1971", "Jacchia-Roberts", "MSIS 1986", "MSISE 1990", "NRLMSISE 2000", Jacchia70Lifetime. The default is Jacchia70Lifetime. |
To set the drag coefficient and rotation option for the ERS1 satellite:
SetLifetime */Satellite/ERS1 DragCoeff 2.123 Rotate On
To set the orbit limit of lifetime calculations for the ERS1 satellite:
SetLifetime */Satellite/ERS1 OrbitLimit 8000
If activated, Connect returns an acknowledgement message.
This command belongs to the following group(s):
7.0
STK Programming Interface 11.0.1