NRLMSISE-00

The NRLMSISE-00 empirical atmosphere model was developed by Mike Picone, Alan Hedin, and Doug Drob based on the MSISE90 model:

Picone, J. M., Hedin, A. E., Drob, D. P., Aikin, A. C (2002). NRLMSISE-00 empirical model of the atmosphere: Statistical comparisons and scientific issues. Journal of Geophysical Research: Space Physics, Vol. 107 (A12), p. SIA 15-1 – SIA 15-16, DOI: 10.1029/2002JA009430.

In this package, we can compute this model using the following functions:

AtmosphericModels.nrlmsise00(instant::DateTime, h::Number, ϕ_gd::Number, λ::Number[, F10ₐ::Number, F10::Number, ap::Union{Number, AbstractVector}]; kwargs...) -> Nrlmsise00Output{Float64}
AtmosphericModels.nrlmsise00(jd::Number, h::Number, ϕ_gd::Number, λ::Number[, F10ₐ::Number, F10::Number, ap::Union{Number, AbstractVector}]; kwargs...) -> Nrlmsise00Output{Float64}

where

• instant::DateTime: Instant to compute the model represent using DateTime.
• jd::Number: Julian day to compute the model.
• h::Number: Altitude [m].
• ϕ_gd::Number: Geodetic latitude [rad].
• λ::Number: Longitude [rad].
• F10ₐ::Number: 10.7-cm averaged solar flux, 90-day centered on input time [sfu].
• F10::Number: 10.7-cm solar flux [sfu].
• ap::Union{Number, AbstractVector}: Magnetic index, see the section AP for more information.

The following keywords are available:

• flags::Nrlmsise00Flags: A list of flags to configure the model. For more information, see AtmosphericModels.Nrlmsise00Flags. (Default = Nrlmsise00Flags())
• include_anomalous_oxygen::Bool: If true, the anomalous oxygen density will be included in the total density computation. (Default = true)
• P::Union{Nothing, Matrix}: If the user passes a matrix with dimensions equal to or greater than 8 × 4, it will be used when computing the Legendre associated functions, reducing allocations and improving the performance. If it is nothing, the matrix is allocated inside the function. (Default nothing)

If we omit all space indices, the system tries to obtain them automatically for the selected day jd or instant. However, the indices must be already initialized using the function SpaceIndices.init().

These functions return an object of type Nrlmsise00Output{Float64} that contains the following fields:

• total_density::T: Total mass density [kg / m³].
• temperature: Temperature at the selected altitude [K].
• exospheric_temperature: Exospheric temperature [K].
• N_number_density: Nitrogen number density [1 / m³].
• N2_number_density: N₂ number density [1 / m³].
• O_number_density: Oxygen number density [1 / m³].
• aO_number_density: Anomalous Oxygen number density [1 / m³].
• O2_number_density: O₂ number density [1 / m³].
• H_number_density: Hydrogen number density [1 / m³].
• He_number_density: Helium number density [1 / m³].
• Ar_number_density: Argon number density [1 / m³].

AP

The input variable ap contains the magnetic index. It can be a Number or an AbstractVector.

If ap is a number, it must contain the daily magnetic index.

If ap is an AbstractVector, it must be a vector with 7 dimensions as described below:

Examples

julia> AtmosphericModels.nrlmsise00(
           DateTime("2018-06-19T18:35:00"),
           700e3,
           deg2rad(-22),
           deg2rad(-45),
           73.5,
           79,
           5.13
       )NRLMSISE-00 Atmospheric Model Result:
          Total density :    7.93093e-15  kg / m³
            Temperature :         837.41  K
       Exospheric Temp. :         837.41  K
      N  number density :    5.59783e+09  1 / m³
      N₂ number density :    5.74331e+07  1 / m³
      O  number density :    1.27057e+11  1 / m³
  Anomalous O num. den. :    2.41856e+09  1 / m³
      O₂ number density :         340465  1 / m³
      Ar number density :        23.1846  1 / m³
      He number density :     6.2485e+11  1 / m³
      H  number density :    1.26678e+11  1 / m³

julia> SpaceIndices.init()
julia> AtmosphericModels.nrlmsise00(DateTime("2018-06-19T18:35:00"), 700e3, deg2rad(-22), deg2rad(-45))NRLMSISE-00 Atmospheric Model Result:
          Total density :    7.58619e-15  kg / m³
            Temperature :         830.21  K
       Exospheric Temp. :         830.21  K
      N  number density :    5.10902e+09  1 / m³
      N₂ number density :    4.94603e+07  1 / m³
      O  number density :    1.16741e+11  1 / m³
  Anomalous O num. den. :    2.41614e+09  1 / m³
      O₂ number density :         287502  1 / m³
      Ar number density :        18.6967  1 / m³
      He number density :    6.15464e+11  1 / m³
      H  number density :    1.28711e+11  1 / m³

If we use the automatic space index fetching mechanism, it is possible to obtain the fetched values by turning on the debugging logs according to the Julia documentation:

julia> using Logging
julia> with_logger(ConsoleLogger(stderr, Logging.Debug)) do
           AtmosphericModels.nrlmsise00(DateTime("2018-06-19T18:35:00"), 700e3, deg2rad(-22), deg2rad(-45))
       end┌ Debug: NRLMSISE00 - Fetched Space Indices
│   Daily F10.7           : 76.1 sfu
│   90-day avareged F10.7 : 73.18444444444442 sfu
│   Ap                    : 5.125
└ @ SatelliteToolboxAtmosphericModels.AtmosphericModels ~/work/SatelliteToolboxAtmosphericModels.jl/SatelliteToolboxAtmosphericModels.jl/src/nrlmsise00/nrlmsise00.jl:180
NRLMSISE-00 Atmospheric Model Result:
          Total density :    7.58619e-15  kg / m³
            Temperature :         830.21  K
       Exospheric Temp. :         830.21  K
      N  number density :    5.10902e+09  1 / m³
      N₂ number density :    4.94603e+07  1 / m³
      O  number density :    1.16741e+11  1 / m³
  Anomalous O num. den. :    2.41614e+09  1 / m³
      O₂ number density :         287502  1 / m³
      Ar number density :        18.6967  1 / m³
      He number density :    6.15464e+11  1 / m³
      H  number density :    1.28711e+11  1 / m³