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

Class 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

    • Field Detail

      • 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 Detail

      • 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 Detail

      • 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
        Kp0o0+1-1o1+2-2o2+3-3o3+4-4o4+
        ap02345679121518222732
        Kp5-5o5+6-6o6+7-7o7+8-8o8+9-9o
        ap394856678094111132154179207236300400
        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 Ap geomagnetic indices.

        Ap indices are provided as an array such as:

        • 0 → daily Ap
        • 1 → 3 hr Ap index for current time
        • 2 → 3 hr Ap index for 3 hrs before current time
        • 3 → 3 hr Ap index for 6 hrs before current time
        • 4 → 3 hr Ap index for 9 hrs before current time
        • 5 → Average of eight 3 hr Ap indices from 12 to 33 hrs prior to current time
        • 6 → Average of eight 3 hr Ap indices from 36 to 57 hrs prior to current time
        Parameters:
        date - the current date
        Returns:
        the array of Ap indices