GeneralAstrodynamics.jl

Common astrodynamics calculations, with hooks into the SciML ecosystem.

JuliaCon Talk

Check out GeneralAstrodynamics in action at JuliaCon 2021! The talk Going to Jupiter with Julia walks through a simple Jupiter mission design while gently introducing astrodynamics, Julia, and GeneralAstrodynamics.

Features

Restricted Two-body Problem (R2BP)

• Structures for Cartesian and Keplerian states, and R2BP systems
• Functions which implement common R2BP equations
• Kepler and Lambert solvers
• Orbit propagation and plotting

Circular Restricted Three-body Problem (CR3BP)

• Structures for dimensioned and normalized Cartesian states, and dimensioned and normalized CR3BP systems
• Functions which implement common CR3BP equations
• Analytical and iterative (numerical) Halo orbit solvers
• Unstable and stable Halo orbit manifold computation
• Orbit propagation and plotting
• Zero-velocity curve computation and plotting

N-body Problem (NBP)

• This was implemented in a previous package version, and is currently being refactored

Usage

using GeneralAstrodynamics

orbit = rand(R2BPOrbit)
trajectory = propagate(orbit, orbital_period(orbit))

furnsh(
    de440s(),                   # position and velocity data for nearby planets
    latest_leapseconds_tls(),   # timekeeping, parsing epochs
    gm_de440(),                 # mass parameters for major solar system bodies
    pck00011(),                 # physical properties of major solar system bodies
)

μ = reduced_mass(
  gm("earth"),
  gm("moon"),
)

orbit, T = let
  u, T = halo(μ, 2; amplitude=1e-2)

  CR3BPOrbit(CartesianState(u), CR3BParameters(μ)), T
end

trajectory = propagate(orbit, T)

Developer documentation

Tests

Run all tests from top-level of monorepo:

> j --proj

(GeneralAstrodynamics) pkg> test

Run all tests for <subpackage> from top-level of monorepo:

> j --proj

ENV["GROUP"] = <subpackage>

(GeneralAstrodynamics) pkg> test

or navigate to top-level of <subpackage> and run tests as usual:

> j --proj

(GeneralAstrodynamics/lib/AstrodynamicalCalculations) pkg> test

List available tests for a given :

> julia --proj

julia> using Pkg

julia> Pkg.test("<subpackage>"; test_args = `--list`)

Run specific tests for a given :

> julia --proj

julia> using Pkg

julia> Pkg.test("<subpackage>"; test_args = `--verbose <filename>`)

for a given filename listed in the previous usage example. Partial matches for the start of the filename are also accepted.

Explicit imports

See the documentation for ExplicitImports.jl for standard usage. For non-package files at path <fpath> relative to the top-level of <subpackage>, run the following:

julia> using ExplicitImports, <subpackage>

julia> include(<fpath>)

julia> print_explicit_imports(Main.<subpackage>Tests, <fpath>)