Merge branch '206-compare-nyx-eclipse-model-to-bsk' into 'master'

One minus fraction slightly decreases SRP error

Closes #206

See merge request !126

src/celestia/eclipse.rs

@@ -16,9 +16,10 @@
     along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */
 
-pub use super::{Cosm, Frame, LTCorr, Orbit, Spacecraft};
+pub use super::{Bodies, Cosm, Frame, LTCorr, Orbit, Spacecraft};
 use crate::md::EventEvaluator;
 use crate::time::{Duration, TimeUnit};
+use crate::TimeTagged;
 use std::cmp::{Eq, Ord, Ordering, PartialOrd};
 use std::fmt;
 use std::sync::Arc;
@@ -335,7 +336,7 @@ pub fn eclipse_state(
         // Compute the nominal area of the light source
         let nominal_area = std::f64::consts::PI * r_ls_prime.powi(2);
         // And return the percentage (between 0 and 1) of the eclipse.
-        EclipseState::Penumbra((nominal_area - shadow_area) / nominal_area)
+        EclipseState::Penumbra(1.0 - shadow_area / nominal_area)
     } else {
         // Annular eclipse.
         // If r_eb_prime is very small, then the fraction is very small: however, we note a penumbra close to 1.0 as near full light source visibility, so let's subtract one from this.

tests/mission_design/force_models.rs

@@ -48,7 +48,7 @@ fn srp_earth_full_vis() {
 
     let (err_r, err_v) = rss_orbit_vec_errors(&final_state.orbit.to_cartesian_vec(), &rslt);
     println!(
-        "Error accumulated in full sunlight over {} : {:.3} m \t{:.3} m/s",
+        "Error accumulated in full sunlight over {} : {:.6} m \t{:.6} m/s",
         prop_time,
         err_r * 1e3,
         err_v * 1e3
@@ -58,7 +58,7 @@ fn srp_earth_full_vis() {
 }
 
 #[test]
-fn srp_earth_penumbra() {
+fn srp_earth_leo() {
     let cosm = Cosm::de438_gmat();
     let eme2k = cosm.frame("EME2000");
 
@@ -98,7 +98,7 @@ fn srp_earth_penumbra() {
 
     let (err_r, err_v) = rss_orbit_vec_errors(&final_state.orbit.to_cartesian_vec(), &rslt);
     println!(
-        "Error accumulated in circular equatorial LEO (with penumbras) over {} : {:.3} m \t{:.3} m/s",
+        "Error accumulated in circular equatorial LEO (with penumbras) over {} : {:.6} m \t{:.6} m/s",
         prop_time,
         err_r * 1e3,
         err_v * 1e3
@@ -148,7 +148,7 @@ fn srp_earth_meo_ecc_inc() {
 
     let (err_r, err_v) = rss_orbit_vec_errors(&final_state.orbit.to_cartesian_vec(), &rslt);
     println!(
-        "Error accumulated in ecc+inc MEO (with penumbras) over {} : {:.3} m \t{:.3} m/s",
+        "Error accumulated in ecc+inc MEO (with penumbras) over {} : {:.6} m \t{:.6} m/s",
         prop_time,
         err_r * 1e3,
         err_v * 1e3