Function uranus_approach_analysis 

pub fn uranus_approach_analysis(
    approach_dir: Vec3<f64>,
    closest_approach_km: f64,
) -> UranusApproachAnalysis

Analyze the approach geometry to Uranus from a given direction.

approach_dir: unit vector of approach direction in ecliptic frame (direction FROM which the spacecraft comes, i.e. opposite of velocity) closest_approach_km: planned closest approach distance from Uranus center