Open-source astronomy and orbital mechanics for your next space project.

use siderust::{
    bodies::solar_system::Sun,
    coordinates::{centers::Geodetic as Site, frames::ECEF},
    qtty::{AstronomicalUnit, DEG, M},
};

fn main() {
    // Seville: longitude east-positive, latitude north-positive.
    let site = Site::<ECEF>::new(-5.9845 * DEG, 37.3891 * DEG, 7.0 * M);

    // The result is already topocentric and horizontal.
    let sun = Sun::get_horizontal::<AstronomicalUnit>(siderust::J2000, site);

    println!("Sun horizontal position: {sun:?}");
    // Altitude is geometric (no refraction); azimuth is north through east.
}

use siderust::{
    bodies::solar_system::Moon,
    coordinates::{
        cartesian::Position,
        centers::Selenocentric,
        frames::EclipticMeanJ2000 as Ecl,
        surface::SurfaceSite,
        transform::{AstroContext, SurfaceHorizontalExt, TransformCenter},
    },
    ephemeris::{Ephemeris, Vsop87Ephemeris},
    qtty::{AstronomicalUnit, DEG, Kilometer, M},
    time::JulianDate,
};

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Lunar site on the IAU mean sphere (lon east, lat planetocentric).
    let site = SurfaceSite::<Moon>::new(20.0 * DEG, (-3.5) * DEG, 0.0 * M)?;
    let jd = JulianDate::new(2_460_000.5); // TT
    let ctx: AstroContext = AstroContext::default();

    // Earth from the Moon centre = −Moon(geocentric), then local Alt/Az.
    let moon_geo = Vsop87Ephemeris::moon_geocentric(jd);
    let earth_sel = Position::<Selenocentric, Ecl, Kilometer>::new(
        -moon_geo.x(), -moon_geo.y(), -moon_geo.z(),
    );
    let earth = site.observe_position(&earth_sel, &jd, &ctx)?;

    let sun_bary = Vsop87Ephemeris::sun_barycentric(jd);
    let sun_sel: Position<Selenocentric, Ecl, AstronomicalUnit> =
        TransformCenter::to_center_with(&sun_bary, (), jd, &ctx);
    let sun = site.observe_position(&sun_sel, &jd, &ctx)?;

    println!("Earth: alt={}, az={}, range={}", earth.alt(), earth.az(), earth.range());
    println!("Sun:   alt={}, az={}, range={}", sun.alt(), sun.az(), sun.range());
    // Geometric only; azimuth north→east. No refraction or terrain.
    Ok(())
}

use siderust::{
    bodies::solar_system::Mars,
    coordinates::{
        cartesian::Position,
        centers::Geocentric,
        frames::EclipticMeanJ2000 as Ecl,
        transform::TransformCenter,
    },
    qtty::AstronomicalUnit,
    time::JulianDate,
};

fn main() {
    type Ecliptic = Position<Geocentric, Ecl, AstronomicalUnit>;

    let jd = JulianDate::new(2_460_001.0);
    let mars_geo: Ecliptic = Mars::vsop87a(jd).to_center(jd);
    println!("Mars geocentric range: {}", mars_geo.distance());
    // Expected ≈ 1.109577 AU
}