empyrean.initialize

initialize(*, data_dir=None, de440_path=None, gm_path=None)[source]

Initialize empyrean with SPICE kernel data.

On first call, loads ephemeris data into a global context. Subsequent calls are no-ops.

If the B612 Foundation data packages (naif-de440, jpl-small-bodies-de441-n16, naif-eop-high-prec, naif-eop-historical, naif-eop-predict, mpc-obscodes) are installed and no explicit paths are provided, empyrean stages a symlinked cache under the platform XDG data directory ($XDG_DATA_HOME/empyrean/b612-cache/ on Linux, ~/Library/Application Support/empyrean/b612-cache/ on macOS, %APPDATA%\empyrean\b612-cache\ on Windows; honors EMPYREAN_DATA_DIR) and uses that as the data directory — zero network access required. Falls back to data_dir (default: same XDG location, data/ instead of b612-cache/) plus download_data() otherwise.

Parameters:

  • data_dir (str | Path | None) – Directory containing kernel files. Overrides B612 detection.

  • de440_path (str | Path | None) – Explicit path to de440.bsp. Overrides B612 detection.

  • gm_path (str | Path | None) – Explicit path to gm_de440.tpc.

Return type:

None