Package org.orekit.models.earth.atmosphere.data

Class MarshallSolarActivityFutureEstimation

java.lang.Object

org.orekit.models.earth.atmosphere.data.AbstractSolarActivityData<MarshallSolarActivityFutureEstimationLoader.LineParameters,MarshallSolarActivityFutureEstimationLoader>

org.orekit.models.earth.atmosphere.data.MarshallSolarActivityFutureEstimation

All Implemented Interfaces:

Serializable, DTM2000InputParameters, NRLMSISE00InputParameters

public class MarshallSolarActivityFutureEstimation
extends AbstractSolarActivityData<MarshallSolarActivityFutureEstimationLoader.LineParameters,MarshallSolarActivityFutureEstimationLoader>

This class provides solar activity data needed by atmospheric models: F107 solar flux, Ap and Kp indexes.

Data comes from the NASA Marshall Solar Activity Future Estimation (MSAFE) as estimates of monthly F10.7 Mean solar flux and Ap geomagnetic parameter (see Marshall Solar Activity website).

Data can be retrieved at the NASA Marshall Solar Activity archived forecast. Here Kp indices are deduced from Ap indexes, which in turn are tabulated equivalent of retrieved Ap values.

If several MSAFE files are available, some dates may appear in several files (for example August 2007 is in all files from the first one published in March 1999 to the February 2008 file). In this case, the data from the most recent file is used and the older ones are discarded. The date of the file is assumed to be 6 months after its first entry (which explains why the file having August 2007 as its first entry is the February 2008 file). This implies that MSAFE files must not be edited to change their time span, otherwise this would break the old entries overriding mechanism.

With these data, the getInstantFlux(AbsoluteDate) and getMeanFlux(AbsoluteDate) methods return the same values and the get24HoursKp(AbsoluteDate) and getThreeHourlyKP(AbsoluteDate) methods return the same values.

Conversion from Ap index values in the MSAFE file to Kp values used by atmosphere models is done using Jacchia's equation in [1].

With these data, the getAp(AbsoluteDate date) method returns an array of seven times the same daily Ap value, i.e. it is suited to be used only with the NRLMSISE00 atmospheric model where the switch #9 is set to 1.

References

1. Jacchia, L. G. "CIRA 1972, recent atmospheric models, and improvements in progress." COSPAR, 21st Plenary Meeting. Vol. 1. 1978.

Author:

Bruno Revelin, Luc Maisonobe, Evan Ward, Pascal Parraud, Vincent Cucchietti

See Also:

• Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	MarshallSolarActivityFutureEstimation.StrengthLevel	Strength level of activity.

Nested classes/interfaces inherited from class org.orekit.models.earth.atmosphere.data.AbstractSolarActivityData

AbstractSolarActivityData.LocalSolarActivity, AbstractSolarActivityData.SolarActivityGenerator

Field Summary

Fields

Modifier and Type	Field	Description
static final String	DEFAULT_SUPPORTED_NAMES	Default regular expression for the supported name that work with all officially published files.

Fields inherited from class org.orekit.models.earth.atmosphere.data.AbstractSolarActivityData

N_NEIGHBORS

Constructor Summary

Constructors

Constructor	Description
MarshallSolarActivityFutureEstimation(String supportedNames, MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel)	Simple constructor.
MarshallSolarActivityFutureEstimation(String supportedNames, MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel, DataProvidersManager dataProvidersManager, TimeScale utc)	Constructor that allows specifying the source of the MSAFE auxiliary data files.
MarshallSolarActivityFutureEstimation(String supportedNames, MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel, DataProvidersManager dataProvidersManager, TimeScale utc, int maxSlots, double maxSpan, double maxInterval, double minimumStep)	Constructor that allows specifying the source of the MSAFE auxiliary data files and customizable thread safe cache configuration.
MarshallSolarActivityFutureEstimation(DataSource source, MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel)	Simple constructor which use the default data context.
MarshallSolarActivityFutureEstimation(DataSource source, MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel, TimeScale utc)	Simple constructor.
MarshallSolarActivityFutureEstimation(DataSource source, MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel, TimeScale utc, int maxSlots, double maxSpan, double maxInterval, double minimumStep)	Constructor with customizable thread safe cache configuration.

Method Summary

Modifier and Type	Method	Description
double	get24HoursKp(AbsoluteDate date)	The Kp index is derived from the Ap index.
double[]	getAp(AbsoluteDate date)	Get the Ap geomagnetic indices.
double	getAverageFlux(AbsoluteDate date)	Get the value of the 81 day average of F10.7 solar flux centered on current day.
double	getDailyFlux(AbsoluteDate date)	Get the value of the daily F10.7 solar flux for previous day.
DateComponents	getFileDate(AbsoluteDate date)	Get the date of the file from which data at the specified date comes from.
double	getInstantFlux(AbsoluteDate date)	Get the value of the instantaneous solar flux.
double	getMeanFlux(AbsoluteDate date)	Get the value of the mean solar flux.
MarshallSolarActivityFutureEstimation.StrengthLevel	getStrengthLevel()	Get the strength level for activity.
double	getThreeHourlyKP(AbsoluteDate date)	Get the value of the 3 hours geomagnetic index.

Methods inherited from class org.orekit.models.earth.atmosphere.data.AbstractSolarActivityData

getCache, getLinearInterpolation, getLinearInterpolation, getMaxDate, getMinDate, getSupportedNames, getUTC

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_SUPPORTED_NAMES

public static final String DEFAULT_SUPPORTED_NAMES

Default regular expression for the supported name that work with all officially published files.

Since:

10.0

See Also:

• Constant Field Values

Constructor Details

MarshallSolarActivityFutureEstimation

@DefaultDataContext
public MarshallSolarActivityFutureEstimation(String supportedNames,
 MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel)

Simple constructor. This constructor uses the default data context.

The original file names used by NASA Marshall space center are of the form: may2019f10_prd.txt or Oct1999F10.TXT. So a recommended regular expression for the supported name that work with all published files is: DEFAULT_SUPPORTED_NAMES.

It provides a default configuration for the thread safe cache :

• Number of slots : OrekitConfiguration.getCacheSlotsNumber()
• Max span : Constants.JULIAN_YEAR
• Max span interval : 0

Parameters:

supportedNames - regular expression for supported files names

strengthLevel - selected strength level of activity

See Also:

• MarshallSolarActivityFutureEstimation(String, StrengthLevel, DataProvidersManager, TimeScale)

MarshallSolarActivityFutureEstimation

public MarshallSolarActivityFutureEstimation(String supportedNames,
 MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel,
 DataProvidersManager dataProvidersManager,
 TimeScale utc)

Constructor that allows specifying the source of the MSAFE auxiliary data files.

It provides a default configuration for the thread safe cache :

• Number of slots : OrekitConfiguration.getCacheSlotsNumber()
• Max span : 31 * Constants.JULIAN_DAY
• Max interval : 0
• Minimum step: 27 * Constants.JULIAN_DAY

Parameters:

supportedNames - regular expression for supported files names

strengthLevel - selected strength level of activity

dataProvidersManager - provides access to auxiliary data files.

utc - UTC time scale.

Since:

10.1

MarshallSolarActivityFutureEstimation

public MarshallSolarActivityFutureEstimation(String supportedNames,
 MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel,
 DataProvidersManager dataProvidersManager,
 TimeScale utc,
 int maxSlots,
 double maxSpan,
 double maxInterval,
 double minimumStep)

Constructor that allows specifying the source of the MSAFE auxiliary data files and customizable thread safe cache configuration.

Parameters:

supportedNames - regular expression for supported files names

strengthLevel - selected strength level of activity

dataProvidersManager - provides access to auxiliary data files.

utc - UTC time scale.

maxSlots - maximum number of independent cached time slots in the time-stamped cache

maxSpan - maximum duration span in seconds of one slot in the time-stamped cache

maxInterval - time interval above which a new slot is created in the time-stamped cache

minimumStep - overriding minimum step designed for non-homogeneous tabulated values. To be used for example when caching monthly tabulated values. May be null.

Since:

10.1

MarshallSolarActivityFutureEstimation

@DefaultDataContext
public MarshallSolarActivityFutureEstimation(DataSource source,
 MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel)

Simple constructor which use the default data context.

It provides a default configuration for the thread safe cache :

• Number of slots : OrekitConfiguration.getCacheSlotsNumber()
• Max span : 31 * Constants.JULIAN_DAY
• Max interval : 0
• Minimum step: 27 * Constants.JULIAN_DAY

Parameters:

source - source for the data

strengthLevel - selected strength level of activity

Since:

12.0

MarshallSolarActivityFutureEstimation

public MarshallSolarActivityFutureEstimation(DataSource source,
 MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel,
 TimeScale utc)

Simple constructor.

It provides a default configuration for the thread safe cache :

• Number of slots : OrekitConfiguration.getCacheSlotsNumber()
• Max span : 31 * Constants.JULIAN_DAY
• Max interval : 0
• Minimum step: 27 * Constants.JULIAN_DAY

Parameters:

source - source for the data

strengthLevel - selected strength level of activity

utc - UTC time scale

Since:

12.0

MarshallSolarActivityFutureEstimation

public MarshallSolarActivityFutureEstimation(DataSource source,
 MarshallSolarActivityFutureEstimation.StrengthLevel strengthLevel,
 TimeScale utc,
 int maxSlots,
 double maxSpan,
 double maxInterval,
 double minimumStep)

Constructor with customizable thread safe cache configuration.

Parameters:

source - source for the data

strengthLevel - selected strength level of activity

utc - UTC time scale

maxSlots - maximum number of independent cached time slots in the time-stamped cache

maxSpan - maximum duration span in seconds of one slot in the time-stamped cache

maxInterval - time interval above which a new slot is created in the time-stamped cache

minimumStep - overriding minimum step designed for non-homogeneous tabulated values. To be used for example when caching monthly tabulated values. Use Double.NaN otherwise.

Since:

12.0

Method Details

getInstantFlux

public double getInstantFlux(AbsoluteDate date)

Get the value of the instantaneous solar flux.

Parameters:

date - the current date

Returns:

the instantaneous solar flux

getMeanFlux

public double getMeanFlux(AbsoluteDate date)

Get the value of the mean solar flux.

Parameters:

date - the current date

Returns:

the mean solar flux

getThreeHourlyKP

public double getThreeHourlyKP(AbsoluteDate date)

Get the value of the 3 hours geomagnetic index. With a delay of 3 hours at pole to 6 hours at equator using: delay=6-abs(lat)*0.033 (lat in deg.)

Parameters:

date - the current date

Returns:

the 3H geomagnetic index

getFileDate

public DateComponents getFileDate(AbsoluteDate date)

Get the date of the file from which data at the specified date comes from.

If several MSAFE files are available, some dates may appear in several files (for example August 2007 is in all files from the first one published in March 1999 to the February 2008 file). In this case, the data from the most recent file is used and the older ones are discarded. The date of the file is assumed to be 6 months after its first entry (which explains why the file having August 2007 as its first entry is the February 2008 file). This implies that MSAFE files must not be edited to change their time span, otherwise this would break the old entries overriding mechanism.

Parameters:

date - date of the solar activity data

Returns:

date of the file

get24HoursKp

public double get24HoursKp(AbsoluteDate date)

The Kp index is derived from the Ap index.

The method used is explained on NOAA website. as follows:

The scale is 0 to 9 expressed in thirds of a unit, e.g. 5- is 4 2/3, 5 is 5 and 5+ is 5 1/3. The ap (equivalent range) index is derived from the Kp index as follows:

Kp / Ap Conversion Table

Kp	0o	0+	1-	1o	1+	2-	2o	2+	3-	3o	3+	4-	4o	4+
ap	0	2	3	4	5	6	7	9	12	15	18	22	27	32
Kp	5-	5o	5+	6-	6o	6+	7-	7o	7+	8-	8o	8+	9-	9o
ap	39	48	56	67	80	94	111	132	154	179	207	236	300	400

Parameters:

date - date of the Kp data

Returns:

the 24H geomagnetic index

getDailyFlux

public double getDailyFlux(AbsoluteDate date)

Get the value of the daily F10.7 solar flux for previous day.

Parameters:

date - the current date

Returns:

the daily F10.7 flux for previous day

getAverageFlux

public double getAverageFlux(AbsoluteDate date)

Description copied from interface: NRLMSISE00InputParameters

Get the value of the 81 day average of F10.7 solar flux centered on current day.

Parameters:

date - the current date

Returns:

the 81 day average of F10.7 solar flux centered on current day

getAp

public double[] getAp(AbsoluteDate date)

Get the A_p geomagnetic indices.

A_p indices are provided as an array such as:

• 0 → daily A_p
• 1 → 3 hr A_p index for current time
• 2 → 3 hr A_p index for 3 hrs before current time
• 3 → 3 hr A_p index for 6 hrs before current time
• 4 → 3 hr A_p index for 9 hrs before current time
• 5 → Average of eight 3 hr A_p indices from 12 to 33 hrs prior to current time
• 6 → Average of eight 3 hr A_p indices from 36 to 57 hrs prior to current time

Parameters:

date - the current date

Returns:

the array of A_p indices

getStrengthLevel

public MarshallSolarActivityFutureEstimation.StrengthLevel getStrengthLevel()

Get the strength level for activity.

Returns:

strength level to set