Changeset 5550

Timestamp:

Nov 18, 2005, 1:12:54 PM (21 years ago)

Author:

Paul Price

Message:

Added earth velocity, and moved nutation to the section under polar
motion, which is where it's supposed to be (according to the
prescription, and Ed's code).

File:

• trunk/doc/pslib/eoc_testing.txt (modified) (6 diffs)

trunk/doc/pslib/eoc_testing.txt

@@ -13 +13 @@
     z=0.7496834983724809
 
-3. Need the Sun position, stuff it into a psSphere (sun).
+3. Stuff the Sun position into a psCube (sunCube):
+
+    x=1.467797790127511E11
+    y=2.5880956908748722E10
+    z=1.1220046291457653E10
+
+Convert to a psSphere (psCubeToSphere *sun).
 
 4. Gravitational deflection:
@@ -25 +31 @@
     z=0.7496835020836093
 
-5. Need the Earth's direction of motion (psSphere *direction) and
-   speed (double speed).
+5. Earth's direction of motion is:
+
+Barycentric velocity of the Earth in m/s:
+    x=5148.713262821658
+    y=-26945.04752348012
+    z=-11682.787302030947
+Diurnal velocity of the observer in m/s:
+    x=-357.6031690489248
+    y=248.46429758174693
+    z=0.09694774143797581
+
+These two need to be summed.  Converting to a psSphere gives the
+direction of motion (psSphere *direction), while the magnitude gives
+the speed (double speed).
 
 6. Aberration:
@@ -40 +58 @@
 7. Generate a psTime (time) for 2003-04-01T01:30:00 UTC.
 
-8. Precession and Nutation
+8. Precession
 
-(a) psEarthPole *earthPN = psEOC_PrecessionModel(time);
+(a) psEarthPole *precession = psEOC_PrecessionModel(time);
 (b) psEarthPole *precessionCorr = psEOC_PrecessionCorr(time, PS_IERS_A);
-(c) psEarthPole *nutationCorr = psEOC_NutationCorr(time);
 
 Add the above components:
 
-    earthPN->x += precessionCorr->x + nutationCorr->x;
-    earthPN->y += precessionCorr->y + nutationCorr->y;
-    earthPN->s += precessionCorr->s + nutationCorr->s;
+    precession->x += precessionCorr->x;
+    precession->y += precessionCorr->y;
+    precession->s += precessionCorr->s;
 
-9. Apply these to the position:
+Apply these to the position:
 
     psSphereRot *precessionNutationInv = psSphereRot_CEOtoGCRS(earth); // This is CEO->GCRS
@@ -64 +81 @@
     z=0.7496183628158023
 
-8. Earth rotation:
+9. Earth rotation:
 
     psSphereRot *earthRotInv = psSphereRot_TEOtoCEO(time); // This is TEO->CEO
@@ -76 +93 @@
     z=0.7496183628158023
 
-9. Polar Motion:
+10. Polar Motion:
 
-   psEarthPole *earthPM = psEOC_GetPolarMotion(time, PS_IERS_A);
+(a) psEarthPole *earthPM = psEOC_GetPolarMotion(time, PS_IERS_A);
+(b) psEarthPole *nutationCorr = psEOC_NutationCorr(time);
+
+Add the above components:
+
+    earthPM->x += nutationCorr->x;
+    earthPM->y += nutationCorr->y;
+    earthPM->s += nutationCorr->s;
+
+Apply these to the position:
+
    psSphereRot *polarMotionInv = psSphereRot_ITRStoTEO(earthPM); // This is ITRS->TEO
    psSphereRot *polarMotion = psSphereRotInvert(polarMotionInv); // This is TEO->ITRS
@@ -89 +116 @@
     z=0.7496169753347885
 
-10. The psLib SDRS does not define functions to go beyond this point
+11. The psLib SDRS does not define functions to go beyond this point
 (specifically, atmospheric refraction correction, and conversion to
 the observer's horizon coordinates), so we stop here.