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Fixed #106 - Calculate rotation axis of Sun, Moon, and planets.

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Don Cross
2021-12-07 15:31:54 -05:00
parent e6c28a9a40
commit 945e70a98f
24 changed files with 866 additions and 161 deletions
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2
source/python/README.md
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@@ -1990,7 +1990,7 @@ See [`AxisInfo`](#AxisInfo) for more detailed information.
Parameters:
body : Body
One of the following values:
`Body.Sun`, `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`,
`Body.Sun`, `Body.Moon`, `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`,
`Body.Jupiter`, `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`.
time : Time
The time at which to calculate the body's rotation axis.

60
source/python/astronomy.py
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@@ -8840,7 +8840,7 @@ def Libration(time):
diam_deg = 2.0 * math.degrees(math.atan(_MOON_MEAN_RADIUS_KM / math.sqrt(dist_km*dist_km - _MOON_MEAN_RADIUS_KM*_MOON_MEAN_RADIUS_KM)))
# Inclination angle
I = math.radians(1.54242)
I = math.radians(1.543)
# Moon's argument of latitude in radians.
f = math.radians(_NormalizeLongitude(93.2720950 + 483202.0175233*t - 0.0036539*t2 - t3/3526000 + t4/863310000))
@@ -9008,7 +9008,7 @@ def RotationAxis(body, time):
Parameters:
body : Body
One of the following values:
`Body.Sun`, `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`,
`Body.Sun`, `Body.Moon`, `Body.Mercury`, `Body.Venus`, `Body.Earth`, `Body.Mars`,
`Body.Jupiter`, `Body.Saturn`, `Body.Uranus`, `Body.Neptune`, `Body.Pluto`.
time : Time
@@ -9043,6 +9043,62 @@ def RotationAxis(body, time):
w = 160.20 - (1.4813688 * d)
elif body == Body.Earth:
return _EarthRotationAxis(time)
elif body == Body.Moon:
# See page 8, Table 2 in:
# https://astropedia.astrogeology.usgs.gov/alfresco/d/d/workspace/SpacesStore/28fd9e81-1964-44d6-a58b-fbbf61e64e15/WGCCRE2009reprint.pdf
E1 = math.radians(125.045 - 0.0529921*d)
E2 = math.radians(250.089 - 0.1059842*d)
E3 = math.radians(260.008 + 13.0120009*d)
E4 = math.radians(176.625 + 13.3407154*d)
E5 = math.radians(357.529 + 0.9856003*d)
E6 = math.radians(311.589 + 26.4057084*d)
E7 = math.radians(134.963 + 13.0649930*d)
E8 = math.radians(276.617 + 0.3287146*d)
E9 = math.radians(34.226 + 1.7484877*d)
E10 = math.radians(15.134 - 0.1589763*d)
E11 = math.radians(119.743 + 0.0036096*d)
E12 = math.radians(239.961 + 0.1643573*d)
E13 = math.radians(25.053 + 12.9590088*d)
ra = (
269.9949 + 0.0031*T
- 3.8787*math.sin(E1)
- 0.1204*math.sin(E2)
+ 0.0700*math.sin(E3)
- 0.0172*math.sin(E4)
+ 0.0072*math.sin(E6)
- 0.0052*math.sin(E10)
+ 0.0043*math.sin(E13)
)
dec = (
66.5392 + 0.0130*T
+ 1.5419*math.cos(E1)
+ 0.0239*math.cos(E2)
- 0.0278*math.cos(E3)
+ 0.0068*math.cos(E4)
- 0.0029*math.cos(E6)
+ 0.0009*math.cos(E7)
+ 0.0008*math.cos(E10)
- 0.0009*math.cos(E13)
)
w = (
38.3213 + (13.17635815 - 1.4e-12*d)*d
+ 3.5610*math.sin(E1)
+ 0.1208*math.sin(E2)
- 0.0642*math.sin(E3)
+ 0.0158*math.sin(E4)
+ 0.0252*math.sin(E5)
- 0.0066*math.sin(E6)
- 0.0047*math.sin(E7)
- 0.0046*math.sin(E8)
+ 0.0028*math.sin(E9)
+ 0.0052*math.sin(E10)
+ 0.0040*math.sin(E11)
+ 0.0019*math.sin(E12)
- 0.0044*math.sin(E13)
)
elif body == Body.Mars:
ra = (
317.269202 - 0.10927547*T