satellitetoolbox-sgp4
SatelliteToolboxSgp4.jl implementing the SGP4/SDP4 orbit propagator for TLE-based orbit prediction. Use when propagating TLEs, fitting TLEs from osculating states, or updating TLE epochs.
Profile →npx skills add majiayu000/claude-skill-registry --skill satellitetoolbox-sgp4 --agent claude-code
Same command for any agent — swap --agent for codex, cursor, copilot.
Weekly change comes from our own snapshots, not the repository page — it measures attention, not adoption.
# SatelliteToolboxSgp4.jl SGP4/SDP4 orbit propagator for TLE-based prediction. Repo: [JuliaSpace/SatelliteToolboxSgp4.jl](https://github.com/JuliaSpace/SatelliteToolboxSgp4.jl) ## Basic Propagation ```julia # One-shot: init + propagate (r_teme, v_teme, sgp4d) = sgp4(t_min, tle) # Two-step: init then propagate sgp4d = sgp4_init(tle) (r_teme, v_teme) = sgp4!(sgp4d, t_min) # t_min = minutes from TLE epoch ``` ## TLE Fitting ```julia # Fit TLE from osculating state vectors (fitted_tle, P) = fit_sgp4_tle(vjd, vr_teme, vv_teme; estimate_bstar=true, max_iterations=50, atol=1e-4, rtol=1e-4) # In-place version (fitted_tle, P) = fit_sgp4_tle!(sgp4d, vjd, vr_teme, vv_teme) ``` ## Epoch Update ```julia new_tle = update_sgp4_tle_epoch(tle, new_epoch_jd) ``` ## Constants ```julia sgp4c_wgs84 # WGS-84 Float64 (default) sgp4c_wgs84_f32 # WGS-84 Float32 sgp4c_wgs72 # WGS-72 Float64 sgp4c_wgs72_f32 # WGS-72 Float32 sgp4d = sgp4_init(tle; sgp4c=sgp4c_wgs72) # Use WGS-72 ``` ## Key Conventions - Propagation time in **minutes** (not seconds!) - Output: position in **km**, velocity in **km/s** - Output frame: **TEME** (True Equator, Mean Equinox) - Returns `SVector{3, T}` - In-place `!` variants for red
- Basic Propagation
- TLE Fitting
- Epoch Update
- Constants
- Key Conventions
What does the satellitetoolbox-sgp4 skill do?
SatelliteToolboxSgp4.jl implementing the SGP4/SDP4 orbit propagator for TLE-based orbit prediction. Use when propagating TLEs, fitting TLEs from osculating states, or updating TLE epochs.
How do I install it?
Run `npx skills add majiayu000/claude-skill-registry --skill satellitetoolbox-sgp4 --agent claude-code` — it drops the skill into your project so the agent can pick it up. Swap the --agent value for codex, cursor or copilot if you use one of those.
Where does this skill come from?
From majiayu000/claude-skill-registry, a repository with 534 stars. We read it straight from the repository tree rather than a submitted listing, so what you see here is what is actually published.
Is a popular skill a good skill?
Not necessarily. Stars measure attention, not adoption — a repository can trend for a week and be abandoned. That is why we show the weekly change from our own snapshots next to the total, instead of a single flattering number.