version updated

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rust-jpl"
-version = "0.0.1"
+version = "0.0.1-alpha"
 edition = "2021"
 authors = ["Chinmay Vivek <iam@chinmayvivek.com>"]
 description = "Rust library for NASA JPL DE441 ephemeris: precise planetary positions for astronomy, astrophysics, and astrology applications"

crates-io.md

@@ -4,3 +4,189 @@
 It provides **high-precision planetary and lunar positions** based on a given **Julian date**, using official **NASA JPL DE ephemerides (DE441)**.
 
 The library is designed for **scientific correctness, API clarity, and performance**, making it suitable for research, engineering, simulation, and educational use.
+
+## 🧭 Use Cases
+
+- Astronomy and astrophysics research
+- Orbital mechanics and trajectory planning
+- Space mission planning
+- Celestial navigation
+- Satellite and ground-station tracking
+- Educational tools and simulations
+- Scientific visualization software
+
+---
+
+## 🛠 Requirements
+
+| Requirement     | Version               |
+| --------------- | --------------------- |
+| **Rust (MSRV)** | **1.70.0** or newer   |
+| Cargo           | Comes with Rust       |
+| Supported OS    | Linux, macOS, Windows |
+| Architecture    | x86_64, aarch64       |
+
+> The MSRV is documented and respected. Breaking MSRV changes will require a minor or major release.
+
+---
+
+## 📦 Installation
+
+### From crates.io
+
+```toml
+[dependencies]
+rust-jpl = "0.0.1-alpha"
+```
+
+---
+
+## 🚀 Quick Start
+
+### Basic Usage
+
+```rust
+use rust_jpl::{Ephemeris, JulianDate};
+
+fn main() -> Result<(), Box<dyn std::error::Error>> {
+    let mut eph = Ephemeris::new("config.toml")?;
+
+    let jd = JulianDate::from_calendar(2024, 1, 15, 12, 0, 0.0)?;
+    let position = eph.get_position("Earth", jd)?;
+
+    println!(
+        "Earth position: ({}, {}, {}) AU",
+        position.x, position.y, position.z
+    );
+
+    Ok(())
+}
+```
+
+---
+
+## ⏱ Time Conversion
+
+```rust
+use rust_jpl::{CalendarDate, JulianDate};
+
+let cal = CalendarDate::new(2024, 1, 15, 12, 0, 0.0);
+let jd = cal.to_julian()?;
+println!("Julian Date: {}", jd.as_f64());
+
+let cal2 = jd.to_calendar();
+println!("Calendar: {}-{:02}-{:02}", cal2.year, cal2.month, cal2.day);
+```
+
+---
+
+## 🪐 Planetary Positions
+
+```rust
+use rust_jpl::{Ephemeris, JulianDate};
+
+let mut eph = Ephemeris::new("config.toml")?;
+let jd = JulianDate::from_calendar(2024, 1, 15, 12, 0, 0.0)?;
+
+let sun = eph.get_position("Sun", jd)?;
+let earth = eph.get_position("Earth", jd)?;
+let mars = eph.get_position("Mars", jd)?;
+
+println!("Sun: ({:.6}, {:.6}, {:.6}) AU", sun.x, sun.y, sun.z);
+println!("Distance from origin: {:.6} AU", sun.distance());
+```
+
+---
+
+## 📊 Ephemeris Metadata
+
+```rust
+use rust_jpl::Ephemeris;
+
+let mut eph = Ephemeris::new("config.toml")?;
+let metadata = eph.get_metadata();
+
+println!("Date Range: {} - {}", metadata.start_year, metadata.end_year);
+println!("Julian Range: {} - {}", metadata.julian_start, metadata.julian_end);
+println!("Interval: {} days", metadata.interval_days);
+println!("Earth–Moon Mass Ratio: {}", metadata.earth_moon_ratio);
+
+for body in eph.get_bodies() {
+    println!("{}: {}", body.name, if body.active { "active" } else { "inactive" });
+}
+```
+
+---
+
+## ⚙️ Configuration
+
+Copy the example configuration file:
+
+```bash
+cp config.toml.example config.toml
+```
+
+### Example `config.toml`
+
+```toml
+[paths]
+nasa_jpl_de441 = "assets/linux_m13000p17000.441.bsp"
+header_441 = "assets/header.441"
+initial_data_dat = "assets/Initial_data.dat"
+```
+
+---
+
+## 📥 Ephemeris File Setup
+
+### 1. Download NASA JPL DE441
+
+- Source: NASA JPL Solar System Dynamics
+- Required files:
+  - `linux_m13000p17000.441`
+  - `header.441`
+
+Rename:
+
+```
+linux_m13000p17000.441 → linux_m13000p17000.441.bsp
+```
+
+Place files in the `assets/` directory.
+
+---
+
+### 2. Create `Initial_data.dat`
+
+```text
+BODIES:
+
+Mercury                 true
+Venus                   true
+EarthMoon_barycenter     true
+Mars                    true
+Jupiter                 true
+Saturn                  true
+Uranus                  true
+Neptune                 true
+Pluto                   true
+Moon_geocentric          true
+Sun                     true
+
+DATE:
+
+Start_year              1940
+End_year                2100
+```
+
+---
+
+## 🧪 Examples
+
+```bash
+cargo run --example basic_usage
+cargo run --example time_conversion
+cargo run --example planetary_positions
+```
+
+---

readme.md

@@ -54,7 +54,7 @@ The library is designed for **scientific correctness, API clarity, and performan
 
 ```toml
 [dependencies]
-rust-jpl = "0.0.1"
+rust-jpl = "0.0.1-alpha"
 ```
 
 ### From source