Crate sgp4

Expand description

This crate implements the SGP4 algorithm for satellite propagation.

It also provides methods to parse Two-Line Element Set (TLE) and Orbit Mean-Elements Message (OMM) data.

A UTF-8 transcript of the mathematical expressions that compose SGP4 can be found in the repository https://github.com/neuromorphicsystems/sgp4.

Example

The following standalone program downloads the lastest Galileo OMMs from Celestrak and predicts the satellites’ positions and velocities after 12 h and 24 h.

fn main() -> sgp4::Result<()> {
    match ureq::get("https://celestrak.com/NORAD/elements/gp.php")
        .query("GROUP", "galileo")
        .query("FORMAT", "json")
        .call()
    {
        Ok(response) => {
            let elements_group: Vec<sgp4::Elements> = response.into_json()?;
            for elements in &elements_group {
                println!("{}", elements.object_name.as_ref().unwrap());
                let constants = sgp4::Constants::from_elements(elements)?;
                for hours in &[12, 24] {
                    println!("    t = {} min", hours * 60);
                    let prediction = constants.propagate((hours * 60) as f64)?;
                    println!("        r = {:?} km", prediction.position);
                    println!("        ṙ = {:?} km.s⁻¹", prediction.velocity);
                }
            }
            Ok(())
        }
        Err(ureq::Error::Status(code, response)) => Err(sgp4::Error::new(format!(
            "network error {}: {}",
            code,
            response.into_string()?
        ))),
        Err(error) => Err(sgp4::Error::new(error.to_string())),
    }
}