pleiades-data 0.5.4

Packaged offline ephemeris data (precomputed Sun, Moon, Mercury through Pluto and 433 Eros positions, derived from JPL public-domain ephemerides) and its EphemerisBackend for the pleiades astrology workspace.
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51

# pleiades-data

[![crates.io](https://img.shields.io/crates/v/pleiades-data.svg)](https://crates.io/crates/pleiades-data)
[![docs.rs](https://img.shields.io/docsrs/pleiades-data)](https://docs.rs/pleiades-data)
[![License: MIT OR Apache-2.0](https://img.shields.io/badge/license-MIT%20OR%20Apache--2.0-blue.svg)](#license)

Packaged offline ephemeris data (precomputed positions for the Sun, the Moon,
Mercury through Pluto and the asteroid 433 Eros, derived from JPL public-domain
ephemerides) and its `EphemerisBackend` for the
[pleiades](https://github.com/rahulmutt/pleiades) astrology workspace.

The crate ships a compressed artifact covering 1900-01-01 through 2100-01-01,
regenerated from the checked-in JPL reference snapshot and validated against a
deterministic binary fixture. It covers the comparison-body planetary set plus
the source-backed custom asteroid `asteroid:433-Eros`, and falls back to other
providers when callers request bodies outside the packaged slice. Enable the
`packaged-artifact-path` feature to load an explicit artifact file for larger
or externally distributed packaged datasets.

## Quick start

```rust
use pleiades_backend::{CelestialBody, Instant, JulianDay, TimeScale};
use pleiades_data::{packaged_backend, packaged_lookup};

let _backend = packaged_backend();
let instant = Instant::new(JulianDay::from_days(2_451_545.0), TimeScale::Tt);
let sun = packaged_lookup(&CelestialBody::Sun, instant)
    .expect("Sun should be in the packaged artifact");
assert!(sun.distance_au.is_some());
```

Besides the packaged bodies, the backend serves six derived lunar points: the
osculating `TrueNode`, `TrueApogee` and `TruePerigee` (from the packaged Moon
state) and the mean `MeanNode`, `MeanApogee` and `MeanPerigee` (from the mean
lunar elements in `pleiades-apsides`). The mean apogee and perigee are the
points on the inclined mean orbit, as Swiss Ephemeris reports `SE_MEAN_APOG`.
All six are served only inside the packaged window.

## Status

Experimental, pre-1.0: breaking changes can land in any minor release. This backend returns mean
geometric coordinates and rejects apparent requests; the chart layer in
`pleiades-core` and the event engines in `pleiades-events` apply apparent
place on top of it. See the
[workspace README](https://github.com/rahulmutt/pleiades#readme) for the full
maturity posture.

## License

MIT OR Apache-2.0