Package org.orekit.models.earth.atmosphere

Class DTM2000

java.lang.Object

org.orekit.models.earth.atmosphere.AbstractSunInfluencedAtmosphere

org.orekit.models.earth.atmosphere.DTM2000

All Implemented Interfaces:

Atmosphere

public class DTM2000
extends AbstractSunInfluencedAtmosphere

This atmosphere model is the realization of the DTM-2000 model.

It is described in the paper:
The DTM-2000 empirical thermosphere model with new data assimilation and constraints at lower boundary: accuracy and properties
S. Bruinsma, G. Thuillier and F. Barlier
Journal of Atmospheric and Solar-Terrestrial Physics 65 (2003) 1053–1070

This model provides dense output for altitudes beyond 120 km.

The model needs geographical and time information to compute general values, but also needs space weather data : mean and instantaneous solar flux and geomagnetic indices.

Mean solar flux is (for the moment) represented by the F10.7 indices. Instantaneous flux can be set to the mean value if the data is not available. Geomagnetic activity is represented by the Kp index, which goes from 1 (very low activity) to 9 (high activity).

All these data can be found on the NOAA (National Oceanic and Atmospheric Administration) website.

Author:

R. Biancale, S. Bruinsma: original fortran routine, Fabien Maussion (java translation)

Constructor Summary

Constructors

Constructor	Description
DTM2000(DTM2000InputParameters parameters, ExtendedPositionProvider sun, BodyShape earth)	Simple constructor for independent computation.
DTM2000(DTM2000InputParameters parameters, ExtendedPositionProvider sun, BodyShape earth, TimeScale utc)	Simple constructor for independent computation.

Method Summary

Modifier and Type	Method	Description
double	getDensity(int day, double alti, double lon, double lat, double hl, double f, double fbar, double akp3, double akp24)	Get the local density with initial entries.
<T extends CalculusFieldElement<T>> T	getDensity(int day, T alti, T lon, T lat, T hl, double f, double fbar, double akp3, double akp24)	Get the local density with initial entries.
double	getDensity(AbsoluteDate date, Vector3D position, Frame frame)	Get the local density.
<T extends CalculusFieldElement<T>> T	getDensity(FieldAbsoluteDate<T> date, FieldVector3D<T> position, Frame frame)	Get the local density.
Frame	getFrame()	Get the frame of the central body.

Methods inherited from class org.orekit.models.earth.atmosphere.AbstractSunInfluencedAtmosphere

getSun, getSunPosition, getSunPosition

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface org.orekit.models.earth.atmosphere.Atmosphere

getVelocity, getVelocity

Constructor Details

DTM2000

@DefaultDataContext
public DTM2000(DTM2000InputParameters parameters,
 ExtendedPositionProvider sun,
 BodyShape earth)

Simple constructor for independent computation.

This constructor uses the default data context.

Parameters:

parameters - the solar and magnetic activity data

sun - the sun position

earth - the earth body shape

See Also:

• DTM2000(DTM2000InputParameters, ExtendedPositionProvider, BodyShape, TimeScale)

DTM2000

public DTM2000(DTM2000InputParameters parameters,
 ExtendedPositionProvider sun,
 BodyShape earth,
 TimeScale utc)

Simple constructor for independent computation.

Parameters:

parameters - the solar and magnetic activity data

sun - the sun position

earth - the earth body shape

utc - UTC time scale.

Since:

10.1

Method Details

getFrame

public Frame getFrame()

Get the frame of the central body.

Returns:

frame of the central body.

getDensity

public double getDensity(int day,
 double alti,
 double lon,
 double lat,
 double hl,
 double f,
 double fbar,
 double akp3,
 double akp24)

Get the local density with initial entries.

Parameters:

day - day of year

alti - altitude in meters

lon - local longitude (rad)

lat - local latitude (rad)

hl - local solar time in rad (O hr = 0 rad)

f - instantaneous solar flux (F10.7)

fbar - mean solar flux (F10.7)

akp3 - 3 hrs geomagnetic activity index (1-9)

akp24 - Mean of last 24 hrs geomagnetic activity index (1-9)

Returns:

the local density (kg/m³)

getDensity

public <T extends CalculusFieldElement<T>> T getDensity(int day,
 T alti,
 T lon,
 T lat,
 T hl,
 double f,
 double fbar,
 double akp3,
 double akp24)

Get the local density with initial entries.

Type Parameters:

T - type of the field elements

Parameters:

day - day of year

alti - altitude in meters

lon - local longitude (rad)

lat - local latitude (rad)

hl - local solar time in rad (O hr = 0 rad)

f - instantaneous solar flux (F10.7)

fbar - mean solar flux (F10.7)

akp3 - 3 hrs geomagnetic activity index (1-9)

akp24 - Mean of last 24 hrs geomagnetic activity index (1-9)

Returns:

the local density (kg/m³)

Since:

9.0

getDensity

public double getDensity(AbsoluteDate date,
 Vector3D position,
 Frame frame)

Get the local density.

Parameters:

date - current date

position - current position in frame

frame - the frame in which is defined the position

Returns:

local density (kg/m³)

getDensity

public <T extends CalculusFieldElement<T>> T getDensity(FieldAbsoluteDate<T> date,
 FieldVector3D<T> position,
 Frame frame)

Get the local density.

Type Parameters:

T - instance of CalculusFieldElement

Parameters:

date - current date

position - current position in frame

frame - the frame in which is defined the position

Returns:

local density (kg/m³)