New ellipsoids

boule/__init__.py

@@ -6,7 +6,27 @@
 #
 # Import functions/classes to make the public API
 from ._ellipsoid import Ellipsoid
-from ._realizations import GRS80, MARS, MERCURY, MOON, VENUS, VESTA, WGS84
+from ._realizations import (
+    EGM96,
+    GRS80,
+    WGS84,
+    Callisto2024,
+    Ceres2018,
+    Charon2024,
+    Enceladus2024,
+    Europa2024,
+    Ganymede2024,
+    Io2024,
+    Mars2009,
+    Mercury2015,
+    Mercury2024,
+    Moon2015,
+    Pluto2024,
+    Titan2024,
+    Venus2015,
+    Vesta2017,
+    Vesta2017_triaxial,
+)
 from ._sphere import Sphere
 from ._triaxialellipsoid import TriaxialEllipsoid
 from ._version import __version__

boule/_realizations.py

@@ -7,13 +7,57 @@
 """
 Ellipsoid and Sphere realizations for the Earth and other planetary bodies.
 """
+import numpy as np
+
 from ._ellipsoid import Ellipsoid
 from ._sphere import Sphere
 from ._triaxialellipsoid import TriaxialEllipsoid
 
+Mercury2015 = Sphere(
+    name="Mercury2015",
+    long_name="Mercury spheroid (2015)",
+    radius=2_439_372,
+    geocentric_grav_const=22.031839224e12,
+    angular_velocity=1.2400172589e-6,
+    reference=(
+        "Wieczorek, MA (2015). 10.05 - Gravity and Topography of the Terrestrial "
+        "Planets, Treatise of Geophysics (Second Edition); Elsevier. "
+        "doi:10.1016/B978-0-444-53802-4.00169-X"
+    ),
+)
+
+Mercury2024 = Sphere(
+    name="Mercury2024",
+    long_name="Mercury spheroid (2023)",
+    radius=2439472.7,
+    geocentric_grav_const=22031815411154.895,
+    angular_velocity=1.2400141739494342e-06,
+    reference=(
+        "R: Maia, J. (2024). Spherical harmonic models of the shape of "
+        "Mercury [Data set]. Zenodo. https://doi.org/10.5281/zenodo.10809345; "
+        "GM, OMEGA: Mazarico, E., et al. (2014), The gravity field, "
+        "orientation, and ephemeris of Mercury from MESSENGER observations "
+        "after three years in orbit, J. Geophys. Res. Planets, 119, "
+        "2417-2436, doi:10.1002/2014JE004675."
+    ),
+)
+
+Venus2015 = Sphere(
+    name="Venus2015",
+    long_name="Venus spheroid (2015)",
+    radius=6_051_878,
+    geocentric_grav_const=324.858592e12,
+    angular_velocity=-299.24e-9,
+    reference=(
+        "Wieczorek, MA (2015). 10.05 - Gravity and Topography of the Terrestrial "
+        "Planets, Treatise of Geophysics (Second Edition); Elsevier. "
+        "doi:10.1016/B978-0-444-53802-4.00169-X"
+    ),
+)
+
 WGS84 = Ellipsoid(
     name="WGS84",
-    long_name="World Geodetic System 1984",
+    long_name="World Geodetic System (1984)",
     semimajor_axis=6378137,
     flattening=1 / 298.257223563,
     geocentric_grav_const=3986004.418e8,
@@ -27,7 +71,7 @@
 
 GRS80 = Ellipsoid(
     name="GRS80",
-    long_name="Geodetic Reference System 1980",
+    long_name="Geodetic Reference System (1980)",
     semimajor_axis=6378137,
     flattening=1 / 298.257222101,
     geocentric_grav_const=3986005.0e8,
@@ -38,10 +82,36 @@
     ),
 )
 
+EGM96 = Ellipsoid(
+    name="EGM96",
+    long_name="Earth Gravitational Model (1996)",
+    semimajor_axis=6378136.3,
+    flattening=1 / 0.298256415099e3,
+    geocentric_grav_const=3986004.415e8,
+    angular_velocity=7292115e-11,
+    reference=(
+        "Lemoine, F. G., et al. (1998). The Development of the Joint NASA "
+        "GSFC and the National Imagery and Mapping Agency (NIMA) Geopotential "
+        "Model EGM96. NASA Goddard Space Flight Center, NASA/TP 1998-206861."
+    ),
+)
 
-MARS = Ellipsoid(
-    name="MARS",
-    long_name="Mars Ellipsoid",
+Moon2015 = Sphere(
+    name="Moon2015",
+    long_name="Moon spheroid (2015)",
+    radius=1_737_151,
+    geocentric_grav_const=4.90280007e12,
+    angular_velocity=2.6617073e-6,
+    reference=(
+        "Wieczorek, MA (2015). 10.05 - Gravity and Topography of the Terrestrial "
+        "Planets, Treatise of Geophysics (Second Edition); Elsevier. "
+        "doi:10.1016/B978-0-444-53802-4.00169-X"
+    ),
+)
+
+Mars2009 = Ellipsoid(
+    name="Mars2009",
+    long_name="Mars ellipsoid (2009)",
     semimajor_axis=3_395_428,
     flattening=(3_395_428 - 3_377_678) / 3_395_428,
     geocentric_grav_const=42828.372e9,
@@ -54,56 +124,210 @@
     ),
 )
 
-VENUS = Sphere(
-    name="VENUS",
-    long_name="Venus Spheroid",
-    radius=6_051_878,
-    geocentric_grav_const=324.858592e12,
-    angular_velocity=-299.24e-9,
+Vesta2017 = Ellipsoid(
+    name="Vesta2017",
+    long_name="Vesta reference ellipsoid (2017)",
+    semimajor_axis=278_556,
+    flattening=(278_556 - 229_921) / 278_556,
+    geocentric_grav_const=17.288e9,
+    angular_velocity=3.267e-4,
     reference=(
-        "Wieczorek, MA (2015). 10.05 - Gravity and Topography of the Terrestrial "
-        "Planets, Treatise of Geophysics (Second Edition); Elsevier. "
-        "doi:10.1016/B978-0-444-53802-4.00169-X"
+        "Karimi, R., Azmoudeh Ardalan, A., & Vasheghani Farahani, S. (2017). "
+        "The size, shape and orientation of the asteroid Vesta based on data "
+        "from the Dawn mission. Earth and Planetary Science Letters, 475, "
+        "71–82. https://doi.org/10.1016/j.epsl.2017.07.033"
     ),
 )
 
-MOON = Sphere(
-    name="MOON",
-    long_name="Moon Spheroid",
-    radius=1_737_151,
-    geocentric_grav_const=4.90280007e12,
-    angular_velocity=2.6617073e-6,
+Vesta2017_triaxial = TriaxialEllipsoid(
+    # Note that this triaxial reference ellipsoid is rotated in longitude
+    # by 8.29 E with respect to the Vesta coordinate system.
+    name="Vesta2017_triaxial",
+    long_name="Vesta triaxial reference ellipsoid (2017)",
+    semimajor_axis=280_413,
+    semimedium_axis=274_572,
+    semiminor_axis=231_253,
+    geocentric_grav_const=17.288e9,
+    angular_velocity=3.267e-4,
     reference=(
-        "Wieczorek, MA (2015). 10.05 - Gravity and Topography of the Terrestrial "
-        "Planets, Treatise of Geophysics (Second Edition); Elsevier. "
-        "doi:10.1016/B978-0-444-53802-4.00169-X"
+        "Karimi, R., Azmoudeh Ardalan, A., & Vasheghani Farahani, S. (2017). "
+        "The size, shape and orientation of the asteroid Vesta based on data "
+        "from the Dawn mission. Earth and Planetary Science Letters, 475, "
+        "71–82. https://doi.org/10.1016/j.epsl.2017.07.033"
     ),
 )
 
-MERCURY = Sphere(
-    name="MERCURY",
-    long_name="Mercury Spheroid",
-    radius=2_439_372,
-    geocentric_grav_const=22.031839221e12,
-    angular_velocity=1.2400172589e-6,
+Ceres2018 = Ellipsoid(
+    name="Ceres2018",
+    long_name="Ceres ellipsoid (2018)",
+    semimajor_axis=482_100,
+    flattening=(482_100 - 445.94) / 482_100,
+    geocentric_grav_const=62629053612.1,
+    angular_velocity=1.9234038694078873e-4,
     reference=(
-        "Wieczorek, MA (2015). 10.05 - Gravity and Topography of the Terrestrial "
-        "Planets, Treatise of Geophysics (Second Edition); Elsevier. "
-        "doi:10.1016/B978-0-444-53802-4.00169-X"
+        "A, F: Park, R. S., et al. (2019). High-resolution shape model of "
+        "Ceres from stereophotoclinometry using Dawn Imaging Data. Icarus, "
+        "319, 812–827. https://doi.org/10.1016/j.icarus.2018.10.024; "
+        "GM, OMEGA: Konopliv, A. S., et al. (2018). The Ceres gravity field, "
+        "spin pole, rotation period and orbit from the Dawn radiometric "
+        "tracking and optical data. Icarus, 299, 411–429. "
+        "https://doi.org/10.1016/j.icarus.2017.08.005"
+    ),
+)
+
+Io2024 = TriaxialEllipsoid(
+    # Best-fit equilibrium shape of Thomas et al. 1998. Their best fit
+    # ellipsoid shape differs by less than 300 m for each axis.
+    name="Io2024",
+    long_name="Io equilibrium triaxial ellipsoid (2024)",
+    semimajor_axis=1_829_700,
+    semimedium_axis=1_819_200,
+    semiminor_axis=1_815_800,
+    geocentric_grav_const=5959.91e9,
+    angular_velocity=2 * np.pi / (1.762732 * 24 * 60 * 60),
+    reference=(
+        "A, B, C: Thomas, P. C., et al. (1998). The Shape of Io from Galileo "
+        "Limb Measurements. Icarus, 135(1), 175–180. "
+        "https://doi.org/10.1006/icar.1998.5987; "
+        "GM: Anderson, J. D., et al. (2001). Io's gravity field and interior "
+        "structure. J. Geophys. Res., 106, 32963–32969. "
+        "https://doi.org/10.1029/2000JE001367; "
+        "OMEGA: R. A. Jacobson (2021), The Orbits of the Regular Jovian "
+        "Satellites and the Orientation of the Pole of Jupiter, personal "
+        "communication to Horizons/NAIF. Accessed via JPL Solar System "
+        "Dynamics, https://ssd.jpl.nasa.gov, JUP365."
+    ),
+)
+
+Europa2024 = TriaxialEllipsoid(
+    # Nominal hydrostatic ellipsoid
+    name="Europa2024",
+    long_name="Europa equilibrium triaxial ellipsoid (2024)",
+    semimajor_axis=1_562_600,
+    semimedium_axis=1_560_100,
+    semiminor_axis=1_559_300,
+    geocentric_grav_const=3202.72e9,
+    angular_velocity=2 * np.pi / (3.525463 * 24 * 60 * 60),
+    reference=(
+        "A, B, C: Nimmo, F., et al. (2007). The global shape of Europa: "
+        "Constraints on lateral shell thickness variations. Icarus, 191(1), "
+        "183–192. https://doi.org/10.1016/j.icarus.2007.04.021"
+        "https://doi.org/10.1006/icar.1998.5987; "
+        "GM: Anderson, J. D., et al. (1998). Europa's differentiated internal "
+        "structure: Inferences from four Galileo encounters. Science, 281, "
+        "2019–2022. https://doi.org/10.1126/science.281.5385.2019; "
+        "OMEGA: R. A. Jacobson (2021), The Orbits of the Regular Jovian "
+        "Satellites and the Orientation of the Pole of Jupiter, personal "
+        "communication to Horizons/NAIF. Accessed via JPL Solar System "
+        "Dynamics, https://ssd.jpl.nasa.gov, JUP365."
+    ),
+)
+
+Ganymede2024 = TriaxialEllipsoid(
+    # Equilibrium ellipsoid III
+    name="Ganymede2024",
+    long_name="Ganymede equilibrium triaxial ellipsoid (2024)",
+    semimajor_axis=2_634_770,
+    semimedium_axis=2_632_380,
+    semiminor_axis=2_631_590,
+    geocentric_grav_const=9.8878041807018262e12,
+    angular_velocity=2 * np.pi / (7.155588 * 24 * 60 * 60),
+    reference=(
+        "A, B, C: Zubarev, A., et al. (2015). New Ganymede control point "
+        "network and global shape model. Planetary and Space Science, 117, "
+        "246–249. https://doi.org/10.1016/j.pss.2015.06.022; "
+        "GM: Gomez Casajus, L., et al. (2022). Gravity Field of Ganymede After "
+        "the Juno Extended Mission. Geophysical Research Letters, 49(24), "
+        "e2022GL099475, doi:10.1029/2022GL099475.; "
+        "OMEGA: R. A. Jacobson (2021), The Orbits of the Regular Jovian "
+        "Satellites and the Orientation of the Pole of Jupiter, personal "
+        "communication to Horizons/NAIF. Accessed via JPL Solar System "
+        "Dynamics, https://ssd.jpl.nasa.gov, JUP365."
+    ),
+)
+
+Callisto2024 = Sphere(
+    name="Callisto2024",
+    long_name="Callisto spheroid (2024)",
+    radius=2_410_300,
+    geocentric_grav_const=7179.292e9,
+    angular_velocity=2 * np.pi / (16.690440 * 24 * 60 * 60),
+    reference=(
+        "R, GM: Anderson, J. D., et al. (2001). Shape, mean radius, gravity "
+        "field, and interior structure of Callisto. Icarus, 153(1), 157–161. "
+        "https://doi.org/10.1006/icar.2001.6664; "
+        "OMEGA: Satellites and the Orientation of the Pole of Jupiter, "
+        "personal communication to Horizons/NAIF. Accessed via JPL Solar "
+        "System Dynamics, https://ssd.jpl.nasa.gov, JUP365."
+    ),
+)
+
+Enceladus2024 = TriaxialEllipsoid(
+    name="Enceladus2024",
+    long_name="Enceladus triaxial ellipsoid (2024)",
+    semimajor_axis=256_140,
+    semimedium_axis=251_160,
+    semiminor_axis=248_680,
+    geocentric_grav_const=7.210443e9,
+    angular_velocity=262.7318870466 * 2.0 * np.pi / 360.0 / (24.0 * 60.0 * 60.0),
+    reference=(
+        "Park, R. S., et al. (2024). The Global Shape, Gravity Field, and "
+        "Libration of Enceladus. Journal of Geophysical Research: Planets, "
+        "129(1), e2023JE008054. https://doi.org/10.1029/2023JE008054"
+    ),
+)
+
+Titan2024 = TriaxialEllipsoid(
+    # Ellispoid fit to data (not from spherical harmonic coefficients)
+    name="Titan2024",
+    long_name="Titan triaxial ellipsoid (2024)",
+    semimajor_axis=2_575_164,
+    semimedium_axis=2_574_720,
+    semiminor_axis=2_574_314,
+    geocentric_grav_const=8978.1383e9,
+    angular_velocity=2 * np.pi / (15.945448 * 24 * 60 * 60),
+    reference=(
+        "A, B, C: Corlies, P., et al. (2017). Titan’s Topography and Shape at "
+        "the End of the Cassini Mission. Geophysical Research Letters, 44(23), "
+        "11,754-11,761. https://doi.org/10.1002/2017GL075518; "
+        "GM: Durante, D., et al. (2019). Titan’s gravity field and interior "
+        "structure after Cassini. Icarus, 326, 123–132. "
+        "https://doi.org/10.1016/j.icarus.2019.03.003; "
+        "OMEGA: Jacobson, R. (2022). The Orbits of the Main Saturnian "
+        "Satellites, the Saturnian System Gravity Field, and the Orientation "
+        "of Saturn's Pole. The Astronomical Journal, 164, 199. "
+        "https://doi.org/10.3847/1538-3881/ac90c9"
+    ),
+)
+
+Pluto2024 = Sphere(
+    name="Pluto2024",
+    long_name="Pluto spheroid (2024)",
+    radius=1_188_300,
+    geocentric_grav_const=869.6e9,
+    angular_velocity=1.1385591834674098e-05,
+    reference=(
+        "R: Nimmo, et al. (2017). Mean radius and shape of Pluto and Charon "
+        "from New Horizons images. Icarus, 287, 12–29. "
+        "https://doi.org/10.1016/j.icarus.2016.06.027; "
+        "GM, OMEGA: Brozović, M., et al. (2015). The orbits and masses of "
+        "satellites of Pluto. Icarus, 246, 317–329. "
+        "https://doi.org/10.1016/j.icarus.2014.03.015; "
     ),
 )
 
-VESTA = TriaxialEllipsoid(
-    name="VESTA",
-    long_name="Vesta Triaxial Ellipsoid",
-    semimajor_axis=286_300,
-    semimedium_axis=278_600,
-    semiminor_axis=223_200,
-    geocentric_grav_const=1.729094e10,
-    angular_velocity=326.71050958367e-6,
+Charon2024 = Sphere(
+    name="Charon2024",
+    long_name="Charon spheroid (2024)",
+    radius=606_000,
+    geocentric_grav_const=105.88e9,
+    angular_velocity=1.1385591834674098e-055,
     reference=(
-        "Russell, C. T., Raymond, C. A., Coradini, A., McSween, H. Y., Zuber, "
-        "M. T., Nathues, A., et al. (2012). Dawn at Vesta: Testing the "
-        "Protoplanetary Paradigm. Science. doi:10.1126/science.1219381"
+        "R: Nimmo, et al. (2017). Mean radius and shape of Pluto and Charon "
+        "from New Horizons images. Icarus, 287, 12–29. "
+        "https://doi.org/10.1016/j.icarus.2016.06.027; "
+        "GM, OMEGA: Brozović, M., et al. (2015). The orbits and masses of "
+        "satellites of Pluto. Icarus, 246, 317–329. "
+        "https://doi.org/10.1016/j.icarus.2014.03.015; "
     ),
 )

boule/tests/test_ellipsoid.py

@@ -13,10 +13,10 @@
 import numpy.testing as npt
 import pytest
 
-from .. import GRS80, MARS, WGS84, Ellipsoid
+from .. import GRS80, WGS84, Ellipsoid, Mars2009
 from .utils import normal_gravity_surface
 
-ELLIPSOIDS = [WGS84, GRS80, MARS]
+ELLIPSOIDS = [WGS84, GRS80, Mars2009]
 ELLIPSOID_NAMES = [e.name for e in ELLIPSOIDS]