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@kuntay/swisseph-data

v0.2.2

Published

Swiss Ephemeris .se1 data files for 1800-2399 CE. Optional companion to @kuntay/swisseph — upgrades calculations from the built-in Moshier theory to the full JPL DE441-derived ephemeris.

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Links

Git

Maintainers

kuntaykuntay

Keywords

swiss-ephemerisephemeris-datase1de441astronomyastrology

Readme

@kuntay/swisseph-data

Swiss Ephemeris .se1 data files for 1800–2399 CE — the optional full-precision companion to @kuntay/swisseph.

2.05 MB. Also served free from jsDelivr and unpkg for browser use.

License: AGPL-3.0-or-later. See NOTICE.

What this is for

@kuntay/swisseph works on its own using the built-in Moshier theory, with no data files. This package upgrades it to the full ephemeris derived from NASA/JPL DE441.

It is an optimisation, not a requirement. Swiss Ephemeris falls back to Moshier automatically when a file is missing or a date falls outside the covered range, so a missing or failed install degrades precision — it does not break anything.

The practical difference is under 6 arcseconds in the worst case (Pluto near 2399) and under 0.07″ for the Sun. That is invisible for astrology and relevant for astronomy or reference fidelity. See the accuracy table.

Contents

| File | Size | Contents | |---|---|---| | sepl_18.se1 | 473 KB | Planets | | semo_18.se1 | 1274 KB | Moon | | seas_18.se1 | 218 KB | Ceres, Pallas, Juno, Vesta, Chiron, Pholus | | sefstars.txt | 133 KB | Fixed star catalogue, 1360 entries | | seorbel.txt | 6 KB | Orbital elements for hypothetical bodies |

Coverage is 1800–2399 CE. Outside that range calculations fall back to Moshier automatically.

Credits

Data files produced by Astrodienst AG from NASA/JPL Development Ephemeris DE441. Upstream: https://github.com/aloistr/swisseph