# -*- coding: utf-8 -*-
# PyMeeus: Python module implementing astronomical algorithms.
# Copyright (C) 2020 Michael Lutz, Sophie Scholz, Vittorio Serra, Sebastian
# Veigl
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program. If not, see <https://www.gnu.org/licenses/>.
from math import sin, cos, sqrt, atan, atan2, radians
from pymeeus.Epoch import Epoch
from pymeeus.Jupiter import Jupiter
from pymeeus.Sun import Sun
"""
.. module:: JupiterMoons
:synopsis: Class to model Jupiter's galilean moons
:license: GNU Lesser General Public License v3 (LGPLv3)
.. moduleauthor:: Michael Lutz, Sophie Scholz, Vittorio Serra, Sebastian Veigl
"""
[docs]class JupiterMoons(object):
"""
Class JupiterMoons models the four galilean satellites of Jupiter. With:
1: Io
2: Europa
3: Ganymede
4: Callisto
The algorithm used can be found in chapter 44 (high accuracy method) of
Meeus' book Astronomic Algorithms
"""
[docs] @staticmethod
def jupiter_system_angles(epoch):
""" This method computes the ascending node of Jupiter as well as
the node of the equator of Jupiter on the ecliptic (psi).
:param epoch: Epoch to compute satellites' positions, as an Epoch
object
:type epoch: :py:class:`Epoch`
:returns: Two float values with the ascending node of Jupiter and psi
:rtype: (float, float)
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> psi_corrected, OMEGA_ascending_node_jupiter = \
JupiterMoons.jupiter_system_angles(utc_1992_12_16_00_00_00)
>>> print(round(psi_corrected, 9))
317.105800921
>>> print(round(OMEGA_ascending_node_jupiter, 9))
100.39249943
"""
# Calculate solar coordinates
O, beta, R = Sun.geometric_geocentric_position(epoch)
# Compute distance Earth - Jupiter (DELTA) by iteration (start value:
# DELTA = 5 AU)
DELTA_old = -1.0
DELTA = 5.0
x = 0.0
y = 0.0
z = 0.0
tau = 0.0
iterations = 0
while DELTA != DELTA_old and iterations < 5:
# Calculate light-time delay
tau = 0.0057755183 * DELTA
l, b, r = Jupiter.geometric_heliocentric_position(epoch - tau)
x = r * cos(b.rad()) * cos(l.rad()) + R * cos(O.rad())
y = r * cos(b.rad()) * sin(l.rad()) + R * sin(O.rad())
z = r * sin(b.rad()) + R * sin(beta.rad())
DELTA_old = DELTA
DELTA = sqrt(x ** 2 + y ** 2 + z ** 2)
iterations += 1
# t is time since JDE 2433000.5 - light time (tau)
t = epoch.jde() - 2443000.5 - tau
# Longitude of the node of the equator of Jupiter on the ecliptic
psi = 316.5182 - 0.00000208 * t
# Calculate precession since epoch B1950.0
T_0 = (epoch.jde() - 2433282.423) / 36525
# Precession in longitude from the epoch B1950.0 in deg
P = 1.3966626 * T_0 + 0.0003088 * (T_0 ** 2)
psi_corrected = psi + P
# Calculate longitude of ascending node (
# OMEGA_ascending_node_jupiter) and inclination on
# the plane of the ecliptic (i_ecliptic_jupiter) in deg
JC_jupiter_angles = (epoch.jde() - tau - 2451545) / 36525
OMEGA_ascending_node_jupiter = 100.464407 + 1.0209774 * \
JC_jupiter_angles + 0.00040315 * (
JC_jupiter_angles ** 2) + \
0.000000404 * (
JC_jupiter_angles ** 3)
return psi_corrected, OMEGA_ascending_node_jupiter
[docs] @staticmethod
def rectangular_positions_jovian_equatorial(
epoch, tofk5=True, solar=False, do_correction=True):
"""This method computes the rectangular geocentric position of
Jupiter's satellites for a given epoch, using the E5-theory.
:param epoch: Epoch to compute satellites' positions, as an Epoch
object
:type epoch: :py:class:`Epoch`
:param tofk5: Whether or not the small correction to convert to the FK5
system will be applied or not
:type tofk5: bool
:param solar: Whether the satellites' positions are observed from the
Earth (False) or the Sun (True)
:type solar: bool
:param do_correction: Whether the satellites' positions is corrected
for the effect of different light-time and perspective effect or
not
:type do_correction: bool
:returns: Four tuple with the rectangular X, Y and Z coordinates in
Jupiter radii (float), where Z is positive if the satellite is more
distant than Jupiter.
:rtype: tuple
:raises: TypeError if input values are of wrong type.
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> io, europa, ganymede, callisto = \
JupiterMoons.rectangular_positions_jovian_equatorial( \
utc_1992_12_16_00_00_00)
>>> print(io)
(-3.450168811390241, 0.21370246960509387, -4.818966623735296)
>>> print(europa)
(7.441869121153001, 0.27524463479625677, -5.747104399729193)
>>> print(ganymede)
(1.201111684800708, 0.5899903274317162, -14.940581367576527)
>>> print(callisto)
(7.072022641384802, 1.0289678450543338, -25.224420329457175)
"""
# Calculate solar coordinates
O, beta, R = Sun.geometric_geocentric_position(epoch, tofk5)
if solar: # Observed from the sun
R = 0
# Compute distance Earth - Jupiter (DELTA) by iteration (start value:
# DELTA = 5 AU)
DELTA_old = -1.0
DELTA = 5.0
x = 0.0
y = 0.0
z = 0.0
tau = 0.0
while DELTA != DELTA_old:
# Calculate light-time delay
tau = 0.0057755183 * DELTA
l, b, r = Jupiter.geometric_heliocentric_position(epoch - tau)
x = r * cos(b.rad()) * cos(l.rad()) + R * cos(O.rad())
y = r * cos(b.rad()) * sin(l.rad()) + R * sin(O.rad())
z = r * sin(b.rad()) + R * sin(beta.rad())
DELTA_old = DELTA
DELTA = sqrt(x ** 2 + y ** 2 + z ** 2)
# Calculate Jupiter's geocentric longitude lambda_0 and latitute beta_0
lambda_0 = atan2(y, x)
beta_0 = atan(z / (sqrt(x ** 2 + y ** 2)))
# t is time since JDE 2433000.5 - light time (tau)
t = epoch.jde() - 2443000.5 - tau
# Mean longitudes of the satellites
l_1 = 106.07719 + 203.488955790 * t
l_2 = 175.73161 + 101.374724735 * t
l_3 = 120.55883 + 50.317609207 * t
l_4 = 84.44459 + 21.571071177 * t
# Longitudes of the perijoves
pi_1 = 97.0881 + 0.16138586 * t
pi_2 = 154.8663 + 0.04726307 * t
pi_3 = 188.1840 + 0.00712734 * t
pi_4 = 335.2868 + 0.00184000 * t
# Longitudes of the nodes on the equatorial plane of Jupiter
omega_1 = 312.3346 - 0.13279386 * t
omega_2 = 100.4411 - 0.03263064 * t
omega_3 = 119.1942 - 0.00717703 * t
omega_4 = 322.6186 - 0.00175934 * t
# Principal inequality in the longitude of Jupiter
GAMMA = 0.33033 * sin(radians(163.679 + 0.0010512 * t)) + \
0.03439 * sin(radians(34.486 - 0.0161731 * t))
# Calculate libration for inner satellites
PHI_lambda = 199.6766 + 0.17379190 * t
# Longitude of the node of the equator of Jupiter on the ecliptic
psi = 316.5182 - 0.00000208 * t
# Mean anomalies of Jupiter and Saturn
G = 30.23756 + 0.0830925701 * t + GAMMA
G_ = 31.97853 + 0.0334597339 * t
# Longitude of the perihelion of Jupiter
PI = 13.469942
# Periodic terms in the longitudes of the satellites
sum1 = 0
sum1 += 0.47259 * sin(2 * radians(l_1 - l_2))
sum1 -= 0.03478 * sin(radians(pi_3 - pi_4))
sum1 += 0.01081 * sin(radians(l_2 - 2 * l_3 + pi_3))
sum1 += 0.00738 * sin(radians(PHI_lambda))
sum1 += 0.00713 * sin(radians(l_2 - 2 * l_3 + pi_2))
sum1 -= 0.00674 * sin(radians(pi_1 + pi_3 - 2 * PI - 2 * G))
sum1 += 0.00666 * sin(radians(l_2 - 2 * l_3 + pi_4))
sum1 += 0.00445 * sin(radians(l_1 - pi_3))
sum1 -= 0.00354 * sin(radians(l_1 - l_2))
sum1 -= 0.00317 * sin(radians(2 * psi - 2 * PI))
sum1 += 0.00265 * sin(radians(l_1 - pi_4))
sum1 -= 0.00186 * sin(radians(G))
sum1 += 0.00162 * sin(radians(pi_2 - pi_3))
sum1 += 0.00158 * sin(radians(4 * (l_1 - l_2)))
sum1 -= 0.00155 * sin(radians(l_1 - l_3))
sum1 -= 0.00138 * sin(radians(psi + omega_3 - 2 * PI - 2 * G))
sum1 -= 0.00115 * sin(radians(2 * (l_1 - 2 * l_2 + omega_2)))
sum1 += 0.00089 * sin(radians(pi_2 - pi_4))
sum1 += 0.00085 * sin(radians(l_1 + pi_3 - 2 * PI - 2 * G))
sum1 += 0.00083 * sin(radians(omega_2 - omega_3))
sum1 += 0.00053 * sin(radians(psi - omega_2))
sum2 = 0
sum2 += 1.06476 * sin(radians(2 * (l_2 - l_3)))
sum2 += 0.04256 * sin(radians(l_1 - 2 * l_2 + pi_3))
sum2 += 0.03581 * sin(radians(l_2 - pi_3))
sum2 += 0.02395 * sin(radians(l_1 - 2 * l_2 + pi_4))
sum2 += 0.01984 * sin(radians(l_2 - pi_4))
sum2 -= 0.01778 * sin(radians(PHI_lambda))
sum2 += 0.01654 * sin(radians(l_2 - pi_2))
sum2 += 0.01334 * sin(radians(l_2 - 2 * l_3 + pi_2))
sum2 += 0.01294 * sin(radians(pi_3 - pi_4))
sum2 -= 0.01142 * sin(radians(l_2 - l_3))
sum2 -= 0.01057 * sin(radians(G))
sum2 -= 0.00775 * sin(radians(2 * (psi - PI)))
sum2 += 0.00524 * sin(radians(2 * (l_1 - l_2)))
sum2 -= 0.00460 * sin(radians((l_1 - l_3)))
sum2 += 0.00316 * sin(radians(psi - 2 * G + omega_3 - 2 * PI))
sum2 -= 0.00203 * sin(radians(pi_1 + pi_3 - 2 * PI - 2 * G))
sum2 += 0.00146 * sin(radians(psi - omega_3))
sum2 -= 0.00145 * sin(radians(2 * G))
sum2 += 0.00125 * sin(radians(psi - omega_4))
sum2 -= 0.00115 * sin(radians(l_1 - 2 * l_3 + pi_3))
sum2 -= 0.00094 * sin(radians(2 * (l_2 - omega_2)))
sum2 += 0.00086 * sin(radians(2 * (l_1 - 2 * l_2 + omega_2)))
sum2 -= 0.00086 * sin(radians(5 * G_ - 2 * G + 52.225))
sum2 -= 0.00078 * sin(radians(l_2 - l_4))
sum2 -= 0.00064 * sin(radians(3 * l_3 - 7 * l_4 + 4 * pi_4))
sum2 += 0.00064 * sin(radians(pi_1 - pi_4))
sum2 -= 0.00063 * sin(radians(l_1 - 2 * l_3 + pi_4))
sum2 += 0.00058 * sin(radians(omega_3 - omega_4))
sum2 += 0.00056 * sin(radians(2 * (psi - PI - G)))
sum2 += 0.00056 * sin(radians(2 * (l_2 - l_4)))
sum2 += 0.00055 * sin(radians(2 * (l_1 - l_3)))
sum2 += 0.00052 * sin(radians(3 * l_3 - 7 * l_4 + pi_3 + 3 * pi_4))
sum2 -= 0.00043 * sin(radians(l_1 - pi_3))
sum2 += 0.00041 * sin(radians(5 * (l_2 - l_3)))
sum2 += 0.00041 * sin(radians(pi_4 - PI))
sum2 += 0.00032 * sin(radians(omega_2 - omega_3))
sum2 += 0.00032 * sin(radians(2 * (l_3 - G - PI)))
sum3 = 0
sum3 += 0.16490 * sin(radians(l_3 - pi_3))
sum3 += 0.09081 * sin(radians(l_3 - pi_4))
sum3 -= 0.06907 * sin(radians(l_2 - l_3))
sum3 += 0.03784 * sin(radians(pi_3 - pi_4))
sum3 += 0.01846 * sin(radians(2 * (l_3 - l_4)))
sum3 -= 0.01340 * sin(radians(G))
sum3 -= 0.01014 * sin(radians(2 * (psi - PI)))
sum3 += 0.00704 * sin(radians(l_2 - 2 * l_3 + pi_3))
sum3 -= 0.00620 * sin(radians(l_2 - 2 * l_3 + pi_2))
sum3 -= 0.00541 * sin(radians(l_3 - l_4))
sum3 += 0.00381 * sin(radians(l_2 - 2 * l_3 + pi_4))
sum3 += 0.00235 * sin(radians(psi - omega_3))
sum3 += 0.00198 * sin(radians(psi - omega_4))
sum3 += 0.00176 * sin(radians(PHI_lambda))
sum3 += 0.00130 * sin(radians(3 * (l_3 - l_4)))
sum3 += 0.00125 * sin(radians(l_1 - l_3))
sum3 -= 0.00119 * sin(radians(5 * G_ - 2 * G + 52.225))
sum3 += 0.00109 * sin(radians(l_1 - l_2))
sum3 -= 0.00100 * sin(radians(3 * l_3 - 7 * l_4 + 4 * pi_4))
sum3 += 0.00091 * sin(radians(omega_3 - omega_4))
sum3 += 0.00080 * sin(radians(3 * l_3 - 7 * l_4 + pi_3 + 3 * pi_4))
sum3 -= 0.00075 * sin(radians(2 * l_2 - 3 * l_3 + pi_3))
sum3 += 0.00072 * sin(radians(pi_1 + pi_3 - 2 * PI - 2 * G))
sum3 += 0.00069 * sin(radians(pi_4 - PI))
sum3 -= 0.00058 * sin(radians(2 * l_3 - 3 * l_4 + pi_4))
sum3 -= 0.00057 * sin(radians(l_3 - 2 * l_4 + pi_4))
sum3 += 0.00056 * sin(radians(l_3 + pi_3 - 2 * PI - 2 * G))
sum3 -= 0.00052 * sin(radians(l_2 - 2 * l_3 + pi_1))
sum3 -= 0.00050 * sin(radians(pi_2 - pi_3))
sum3 += 0.00048 * sin(radians(l_3 - 2 * l_4 + pi_3))
sum3 -= 0.00045 * sin(radians(2 * l_2 - 3 * l_3 + pi_4))
sum3 -= 0.00041 * sin(radians(pi_2 - pi_4))
sum3 -= 0.00038 * sin(radians(2 * G))
sum3 -= 0.00037 * sin(radians(pi_3 - pi_4 + omega_3 - omega_4))
sum3 -= 0.00032 * sin(radians(3 * l_3 - 7 * l_4 + 2 * pi_3 + 2 * pi_4))
sum3 += 0.00030 * sin(radians(4 * (l_3 - l_4)))
sum3 += 0.00029 * sin(radians(l_3 + pi_4 - 2 * PI - 2 * G))
sum3 -= 0.00028 * sin(radians(omega_3 + psi - 2 * PI - 2 * G))
sum3 += 0.00026 * sin(radians(l_3 - PI - G))
sum3 += 0.00024 * sin(radians(l_2 - 3 * l_3 + 2 * l_4))
sum3 += 0.00021 * sin(radians(2 * (l_3 - PI - G)))
sum3 -= 0.00021 * sin(radians(l_3 - pi_2))
sum3 += 0.00017 * sin(radians(2 * (l_3 - pi_3)))
sum4 = 0
sum4 += 0.84287 * sin(radians(l_4 - pi_4))
sum4 += 0.03431 * sin(radians(pi_4 - pi_3))
sum4 -= 0.03305 * sin(radians(2 * (psi - PI)))
sum4 -= 0.03211 * sin(radians(G))
sum4 -= 0.01862 * sin(radians(l_4 - pi_3))
sum4 += 0.01186 * sin(radians(psi - omega_4))
sum4 += 0.00623 * sin(radians(l_4 + pi_4 - 2 * G - 2 * PI))
sum4 += 0.00387 * sin(radians(2 * (l_4 - pi_4)))
sum4 -= 0.00284 * sin(radians(5 * G_ - 2 * G + 52.225))
sum4 -= 0.00234 * sin(radians(2 * (psi - pi_4)))
sum4 -= 0.00223 * sin(radians(l_3 - l_4))
sum4 -= 0.00208 * sin(radians(l_4 - PI))
sum4 += 0.00178 * sin(radians(psi + omega_4 - 2 * pi_4))
sum4 += 0.00134 * sin(radians(pi_4 - PI))
sum4 += 0.00125 * sin(radians(2 * (l_4 - G - PI)))
sum4 -= 0.00117 * sin(radians(2 * G))
sum4 -= 0.00112 * sin(radians(2 * (l_3 - l_4)))
sum4 += 0.00107 * sin(radians(3 * l_3 - 7 * l_4 + 4 * pi_4))
sum4 += 0.00102 * sin(radians(l_4 - G - PI))
sum4 += 0.00096 * sin(radians(2 * l_4 - psi - omega_4))
sum4 += 0.00087 * sin(radians(2 * (psi - omega_4)))
sum4 -= 0.00085 * sin(radians(3 * l_3 - 7 * l_4 + pi_3 + 3 * pi_4))
sum4 += 0.00085 * sin(radians(l_3 - 2 * l_4 + pi_4))
sum4 -= 0.00081 * sin(radians(2 * (l_4 - psi)))
sum4 += 0.00071 * sin(radians(l_4 + pi_4 - 2 * PI - 3 * G))
sum4 += 0.00061 * sin(radians(l_1 - l_4))
sum4 -= 0.00056 * sin(radians(psi - omega_3))
sum4 -= 0.00054 * sin(radians(l_3 - 2 * l_4 + pi_3))
sum4 += 0.00051 * sin(radians(l_2 - l_4))
sum4 += 0.00042 * sin(radians(2 * (psi - G - PI)))
sum4 += 0.00039 * sin(radians(2 * (pi_4 - omega_4)))
sum4 += 0.00036 * sin(radians(psi + PI - pi_4 - omega_4))
sum4 += 0.00035 * sin(radians(2 * G_ - G + 188.37))
sum4 -= 0.00035 * sin(radians(l_4 - pi_4 + 2 * PI - 2 * psi))
sum4 -= 0.00032 * sin(radians(l_4 + pi_4 - 2 * PI - G))
sum4 += 0.00030 * sin(radians(2 * G_ - 2 * G + 149.15))
sum4 += 0.00029 * sin(radians(3 * l_3 - 7 * l_4 + 2 * pi_3 + 2 * pi_4))
sum4 += 0.00028 * sin(radians(l_4 - pi_4 + 2 * psi - 2 * PI))
sum4 -= 0.00028 * sin(radians(2 * (l_4 - omega_4)))
sum4 -= 0.00027 * sin(radians(pi_3 - pi_4 + omega_3 - omega_4))
sum4 -= 0.00026 * sin(radians(5 * G_ - 3 * G + 188.37))
sum4 += 0.00025 * sin(radians(omega_4 - omega_3))
sum4 -= 0.00025 * sin(radians(l_2 - 3 * l_3 + 2 * l_4))
sum4 -= 0.00023 * sin(radians(3 * (l_3 - l_4)))
sum4 += 0.00021 * sin(radians(2 * l_4 - 2 * PI - 3 * G))
sum4 -= 0.00021 * sin(radians(2 * l_3 - 3 * l_4 + pi_4))
sum4 += 0.00019 * sin(radians(l_4 - pi_4 - G))
sum4 -= 0.00019 * sin(radians(2 * l_4 - pi_3 - pi_4))
sum4 -= 0.00018 * sin(radians(l_4 - pi_4 + G))
sum4 -= 0.00016 * sin(radians(l_4 + pi_3 - 2 * PI - 2 * G))
# True longitudes of the satellites
L1 = l_1 + sum1
L2 = l_2 + sum2
L3 = l_3 + sum3
L4 = l_4 + sum4
# Periodic terms in the latitudes of the satellites
tan_B1 = +0.0006393 * sin(radians(L1 - omega_1)) \
+ 0.0001825 * sin(radians(L1 - omega_2)) \
+ 0.0000329 * sin(radians(L1 - omega_3)) \
- 0.0000311 * sin(radians(L1 - psi)) \
+ 0.0000093 * sin(radians(L1 - omega_4)) \
+ 0.0000075 * sin(
radians(3 * L1 - 4 * l_2 - 1.9927 * sum1 + omega_2)) \
+ 0.0000046 * sin(radians(L1 + psi - 2 * PI - 2 * G))
tan_B2 = +0.0081004 * sin(radians(L2 - omega_2)) \
+ 0.0004512 * sin(radians(L2 - omega_3)) \
- 0.0003284 * sin(radians(L2 - psi)) \
+ 0.0001160 * sin(radians(L2 - omega_4)) \
+ 0.0000272 * sin(
radians(l_1 - 2 * l_3 + 1.0146 * sum2 + omega_2)) \
- 0.0000144 * sin(radians(L2 - omega_1)) \
+ 0.0000143 * sin(radians(L2 + psi - 2 * PI - 2 * G)) \
+ 0.0000035 * sin(radians(L2 - psi + G)) \
- 0.0000028 * sin(
radians(l_1 - 2 * l_3 + 1.0146 * sum2 + omega_3))
tan_B3 = +0.0032402 * sin(radians(L3 - omega_3)) \
- 0.0016911 * sin(radians(L3 - psi)) \
+ 0.0006847 * sin(radians(L3 - omega_4)) \
- 0.0002797 * sin(radians(L3 - omega_2)) \
+ 0.0000321 * sin(radians(L3 + psi - 2 * PI - 2 * G)) \
+ 0.0000051 * sin(radians(L3 - psi + G)) \
- 0.0000045 * sin(radians(L3 - psi - G)) \
- 0.0000045 * sin(radians(L3 + psi - 2 * PI)) \
+ 0.0000037 * sin(radians(L3 + psi - 2 * PI - 3 * G)) \
+ 0.0000030 * sin(
radians(2 * l_2 - 3 * L3 + 4.03 * sum3 + omega_2)) \
- 0.0000021 * \
sin(radians(2 * l_2 - 3 * L3 + 4.03 * sum3 + omega_3))
tan_B4 = -0.0076579 * sin(radians(L4 - psi)) \
+ 0.0044134 * sin(radians(L4 - omega_4)) \
- 0.0005112 * sin(radians(L4 - omega_3)) \
+ 0.0000773 * sin(radians(L4 + psi - 2 * PI - 2 * G)) \
+ 0.0000104 * sin(radians(L4 - psi + G)) \
- 0.0000102 * sin(radians(L4 - psi - G)) \
+ 0.0000088 * sin(radians(L4 + psi - 2 * PI - 3 * G)) \
- 0.0000038 * sin(radians(L4 + psi - 2 * PI - G))
B_1_rad = atan(tan_B1)
B_2_rad = atan(tan_B2)
B_3_rad = atan(tan_B3)
B_4_rad = atan(tan_B4)
# Periodic terms for the radius vector
sum_r_1 = -0.0041339 * cos(radians((2 * (l_1 - l_2))))
sum_r_1 -= 0.0000387 * cos(radians((l_1 - pi_3)))
sum_r_1 -= 0.0000214 * cos(radians((l_1 - pi_4)))
sum_r_1 += 0.0000170 * cos(radians((l_1 - l_2)))
sum_r_1 -= 0.0000131 * cos(radians((4 * (l_1 - l_2))))
sum_r_1 += 0.0000106 * cos(radians((l_1 - l_3)))
sum_r_1 -= 0.0000066 * cos(radians((l_1 + pi_3 - 2 * PI - 2 * G)))
sum_r_2 = +0.0093848 * cos(radians((l_1 - l_2)))
sum_r_2 -= 0.0003116 * cos(radians((l_2 - pi_3)))
sum_r_2 -= 0.0001744 * cos(radians((l_2 - pi_4)))
sum_r_2 -= 0.0001442 * cos(radians((l_2 - pi_2)))
sum_r_2 += 0.0000553 * cos(radians((l_2 - l_3)))
sum_r_2 += 0.0000523 * cos(radians((l_1 - l_3)))
sum_r_2 -= 0.0000290 * cos(radians((2 * (l_1 - l_2))))
sum_r_2 += 0.0000164 * cos(radians((2 * (l_2 - omega_2))))
sum_r_2 += 0.0000107 * cos(radians((l_1 - 2 * l_3 + pi_3)))
sum_r_2 -= 0.0000102 * cos(radians((l_2 - pi_1)))
sum_r_2 -= 0.0000091 * cos(radians((2 * (l_1 - l_3))))
sum_r_3 = -0.0014388 * cos(radians((l_3 - pi_3)))
sum_r_3 -= 0.0007919 * cos(radians((l_3 - pi_4)))
sum_r_3 += 0.0006342 * cos(radians((l_2 - l_3)))
sum_r_3 -= 0.0001761 * cos(radians((2 * (l_3 - l_4))))
sum_r_3 += 0.0000294 * cos(radians((l_3 - l_4)))
sum_r_3 -= 0.0000156 * cos(radians((3 * (l_3 - l_4))))
sum_r_3 += 0.0000156 * cos(radians((l_1 - l_3)))
sum_r_3 -= 0.0000153 * cos(radians((l_1 - l_2)))
sum_r_3 += 0.0000070 * cos(radians((2 * l_2 - 3 * l_3 + pi_3)))
sum_r_3 -= 0.0000051 * cos(radians((l_3 + pi_3 - 2 * PI - 2 * G)))
sum_r_4 = -0.0073546 * cos(radians((l_4 - pi_4)))
sum_r_4 += 0.0001621 * cos(radians((l_4 - pi_3)))
sum_r_4 += 0.0000974 * cos(radians((l_3 - l_4)))
sum_r_4 -= 0.0000543 * cos(radians((l_4 + pi_4 - 2 * PI - 2 * G)))
sum_r_4 -= 0.0000271 * cos(radians((2 * (l_4 - pi_4))))
sum_r_4 += 0.0000182 * cos(radians((l_4 - PI)))
sum_r_4 += 0.0000177 * cos(radians((2 * (l_3 - l_4))))
sum_r_4 -= 0.0000167 * cos(radians((2 * l_4 - psi - omega_4)))
sum_r_4 += 0.0000167 * cos(radians((psi - omega_4)))
sum_r_4 -= 0.0000155 * cos(radians((2 * (l_4 - PI - G))))
sum_r_4 += 0.0000142 * cos(radians((2 * (l_4 - psi))))
sum_r_4 += 0.0000105 * cos(radians((l_1 - l_4)))
sum_r_4 += 0.0000092 * cos(radians((l_2 - l_4)))
sum_r_4 -= 0.0000089 * cos(radians((l_4 - PI - G)))
sum_r_4 -= 0.0000062 * cos(radians((l_4 + pi_4 - 2 * PI - 3 * G)))
sum_r_4 += 0.0000048 * cos(radians((2 * (l_4 - omega_4))))
# Mean distances of the satellites
a1 = 5.90569
a2 = 9.39657
a3 = 14.98832
a4 = 26.36273
# Radius vector of the satellites in equatorial radii of Jupiter
R_1 = a1 * (1 + sum_r_1)
R_2 = a2 * (1 + sum_r_2)
R_3 = a3 * (1 + sum_r_3)
R_4 = a4 * (1 + sum_r_4)
# Calculate precession since epoch B1950.0
T_0 = (epoch.jde() - 2433282.423) / 36525
# Precession in longitude from the epoch B1950.0 in deg
P = 1.3966626 * T_0 + 0.0003088 * (T_0 ** 2)
# Correct all longitudes and psi by precession
L1_corrected = L1 + P
L2_corrected = L2 + P
L3_corrected = L3 + P
L4_corrected = L4 + P
psi_corrected = psi + P
# Cartesian coordinates of the four satellites referred to Jupiter in
# Jupiter's radii
X_1 = R_1 * cos(radians(L1_corrected - psi_corrected)) * cos(B_1_rad)
Y_1 = R_1 * sin(radians(L1_corrected - psi_corrected)) * cos(B_1_rad)
Z_1 = R_1 * sin(B_1_rad)
X_2 = R_2 * cos(radians(L2_corrected - psi_corrected)) * cos(B_2_rad)
Y_2 = R_2 * sin(radians(L2_corrected - psi_corrected)) * cos(B_2_rad)
Z_2 = R_2 * sin(B_2_rad)
X_3 = R_3 * cos(radians(L3_corrected - psi_corrected)) * cos(B_3_rad)
Y_3 = R_3 * sin(radians(L3_corrected - psi_corrected)) * cos(B_3_rad)
Z_3 = R_3 * sin(B_3_rad)
X_4 = R_4 * cos(radians(L4_corrected - psi_corrected)) * cos(B_4_rad)
Y_4 = R_4 * sin(radians(L4_corrected - psi_corrected)) * cos(B_4_rad)
Z_4 = R_4 * sin(B_4_rad)
# Fictional fifth satellite
X_5 = 0
Y_5 = 0
Z_5 = 1
# Calculate longitude of ascending node (
# OMEGA_asc_node_jup) and inclination on
# the plane of the ecliptic (i_ecliptic_jupiter) in deg
JC_jupiter_angles = (epoch.jde() - tau - 2451545) / 36525
OMEGA_asc_node_jup = 100.464407 + 1.0209774 * \
JC_jupiter_angles + 0.00040315 * (
JC_jupiter_angles ** 2) + \
0.000000404 * (
JC_jupiter_angles ** 3)
i_ecliptic_jupiter = 1.303267 - 0.0054965 * JC_jupiter_angles + \
0.00000466 * (
JC_jupiter_angles ** 2) - 0.000000002 * (
JC_jupiter_angles ** 3)
# Calculate D with the fictional satellite
D = JupiterMoons.apparent_rectangular_coordinates(epoch, X_5, Y_5, Z_5,
OMEGA_asc_node_jup,
psi_corrected,
i_ecliptic_jupiter,
lambda_0, beta_0,
isFictional=True)
# Calculate rectangular Coordinates X, Y and Z in Jupiter's radii of
# Io (1), Europa (2),
# Ganimed (3) and Callisto (4)
Io = JupiterMoons. \
apparent_rectangular_coordinates(epoch, X_1, Y_1,
Z_1,
OMEGA_asc_node_jup,
psi_corrected,
i_ecliptic_jupiter,
lambda_0, beta_0, D)
Europa = JupiterMoons. \
apparent_rectangular_coordinates(epoch, X_2, Y_2,
Z_2,
OMEGA_asc_node_jup,
psi_corrected,
i_ecliptic_jupiter,
lambda_0,
beta_0, D)
Ganimed = JupiterMoons. \
apparent_rectangular_coordinates(epoch, X_3,
Y_3, Z_3,
OMEGA_asc_node_jup,
psi_corrected,
i_ecliptic_jupiter,
lambda_0,
beta_0, D)
Callisto = JupiterMoons. \
apparent_rectangular_coordinates(epoch, X_4,
Y_4, Z_4,
OMEGA_asc_node_jup,
psi_corrected,
i_ecliptic_jupiter,
lambda_0,
beta_0, D)
# Calculate corrected coordinates
if do_correction:
Io = JupiterMoons.correct_rectangular_positions(R_1, 1, DELTA, Io)
Europa = JupiterMoons.correct_rectangular_positions(
R_2, 2, DELTA, Europa)
Ganimed = JupiterMoons.correct_rectangular_positions(
R_3, 3, DELTA, Ganimed)
Callisto = JupiterMoons.correct_rectangular_positions(
R_4, 4, DELTA, Callisto)
return Io, Europa, Ganimed, Callisto
[docs] @staticmethod
def apparent_rectangular_coordinates(
epoch, X, Y, Z, OMEGA, psi, i, lambda_0, beta_0, D=0,
isFictional=False):
"""This method computes the apparent rectangular coordinates of a
Jupiter satellite for given coordinates.
:param epoch: Epoch to compute satellite position, as an Epoch object
:type epoch: :py:class:`Epoch`
:param X: X-coordinate of the satellite in Jupiter radii
:type X: float
:param Y: Y-coordinate of the satellite in Jupiter radii
:type Y: float
:param Z: Z-coordinate of the satellite in Jupiter radii
:type Z: float
:param OMEGA: longitude of the node of Jupiter
:type OMEGA: float
:param psi: longitude of the node of Jupiter
:type psi: float
:param i: inclination on the plane of the ecliptic
:type i: float
:param beta_0: Jupiter’s geocentric latitude
:type beta_0: float
:param lambda_0: Jupiter’s geocentric longitude
:type lambda_0: float
:param D: parameter calculated by the fifth fictional satellite
(fictional satellite has to be calculated first, in order to
calculate the coordinates of the remaining "true" satellites)
:type D: float
:param isFictional: Whether or not the satellite is the fictional
satellite No. 5
:type isFictional: bool
:returns: A tuple with the apparent rectangular coordinates of the
satellite or parameter D if isFictional=True
:rtype: tuple, float
:raises: TypeError if input values are wrong type
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> psi_corrected = 317.1058009213959
>>> i_ecliptic_jupiter = 1.3036541530886598
>>> lambda_0 = -2.9355662143229146
>>> beta_0 = 0.021667777174910842
>>> OMEGA_ascending_node_jupiter= 100.39249942976576
>>> X_1 = 5.60361395790844
>>> Y_1 = 1.9398758261880644
>>> Z_1 = 0.00449258104769796
>>> X_5 = 0
>>> Y_5 = 0
>>> Z_5 = 1
>>> d = JupiterMoons.apparent_rectangular_coordinates( \
utc_1992_12_16_00_00_00, X_5, Y_5, Z_5, \
OMEGA_ascending_node_jupiter, psi_corrected, i_ecliptic_jupiter, \
lambda_0, beta_0, isFictional=True)
>>> print(round(d, 10))
-0.0320562469
>>> io = JupiterMoons.apparent_rectangular_coordinates( \
utc_1992_12_16_00_00_00, X_1, Y_1, Z_1, \
OMEGA_ascending_node_jupiter, psi_corrected, i_ecliptic_jupiter, \
lambda_0, beta_0, d)
>>> print(io)
(-3.4489935969836503, 0.21361563816963675, -4.818966623735296)
"""
# Checking for type
if not isinstance(epoch, Epoch):
raise TypeError("Invalid input types")
# Time in centuries since 1900.0
time_JC_1900 = (epoch.jde() - 2415020.50000) / \
36525 # leave out final .5
# Inclination of Jupiter's orbit with respect to the orbital plane
Inc = 3.120262 + 0.0006 * time_JC_1900
# Rotate towards Jupiter's orbital plane
A_1 = X
B_1 = Y * cos(radians(Inc)) - Z * sin(radians(Inc))
C_1 = Y * sin(radians(Inc)) + Z * cos(radians(Inc))
# Rotate towards the ascending node of Jupiter's orbit
PHI = psi - OMEGA
A_2 = A_1 * cos(radians(PHI)) - B_1 * sin(radians(PHI))
B_2 = A_1 * sin(radians(PHI)) + B_1 * cos(radians(PHI))
C_2 = C_1
# Rotate towards the plane of the ecliptic
A_3 = A_2
B_3 = B_2 * cos(radians(i)) - C_2 * sin(radians(i))
C_3 = B_2 * sin(radians(i)) + C_2 * cos(radians(i))
# Rotate towards the vernal equinox
A_4 = A_3 * cos(radians(OMEGA)) - B_3 * sin(radians(OMEGA))
B_4 = A_3 * sin(radians(OMEGA)) + B_3 * cos(radians(OMEGA))
C_4 = C_3
A_5 = A_4 * sin(lambda_0) - B_4 * cos(lambda_0)
B_5 = A_4 * cos(lambda_0) + B_4 * sin(lambda_0)
C_5 = C_4
A_6 = A_5
B_6 = C_5 * sin(beta_0) + B_5 * cos(beta_0)
C_6 = C_5 * cos(beta_0) - B_5 * sin(beta_0)
if isFictional: # for fictional satellite No. 5
# Calculate D
zeta = A_6
eta = C_6
D = atan2(zeta, eta)
return D
else: # for remaining true satellites No. 1-4
X = A_6 * cos(D) - C_6 * sin(D)
Y = A_6 * sin(D) + C_6 * cos(D)
Z = B_6
return X, Y, Z
[docs] @staticmethod
def calculate_delta(epoch):
"""This method calculates the distance between Earth and Jupiter
(DELTA) for a given epoch by iteration.
:param epoch: Epoch the distance should be calculated for.
:type epoch: :py:class:`Epoch`
:returns: Distance Earth-Jupiter in AU and light-time delay from
Earth-Jupiter, together with Coordinates of Jupiter
:rtype: tuple
:raises: TypeError if input values are wrong type
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> delta, tau, l, b, r = JupiterMoons.calculate_delta( \
utc_1992_12_16_00_00_00)
>>> print(round(delta, 10))
5.6611211815
>>> print(round(tau, 10))
0.032695909
"""
# Calculate solar coordinates
O, beta, R = Sun.geometric_geocentric_position(epoch)
# Compute distance Earth - Jupiter (DELTA) by iteration (start value:
# DELTA = 5 AU)
DELTA_old = -1.0
DELTA = 5.0
x = 0.0
y = 0.0
z = 0.0
tau = 0.0
l, b, r = 0, 0, 0
iterations = 0
while DELTA != DELTA_old and iterations < 5:
# Calculate light-time delay
tau = 0.0057755183 * DELTA
l, b, r = Jupiter.geometric_heliocentric_position(epoch - tau)
x = r * cos(b.rad()) * cos(l.rad()) + R * cos(O.rad())
y = r * cos(b.rad()) * sin(l.rad()) + R * sin(O.rad())
z = r * sin(b.rad()) + R * sin(beta.rad())
DELTA_old = DELTA
DELTA = sqrt(x ** 2 + y ** 2 + z ** 2)
iterations += 1
return DELTA, tau, l, b, r
[docs] @staticmethod
def correct_rectangular_positions(
R, i_sat, DELTA, X_coordinate, Y_coordinate=0, Z_coordinate=0):
"""This method corrects the given rectangular coordinates of a Jupiter
satellite in order to obtain higher accuracy by considering
differential light-time and the perspective effect.
:param R: Radius vector of the satellite
:type R: float
:param i_sat: Number of the satellite
:type i_sat: int
:param DELTA: Distance Observer-Jupiter in AU
:type DELTA: float
:param X_coordinate: Uncorrected X-coordinate of the satellite in
Jupiter's radii or tuple for all coordinates
:type X_coordinate: float, tuple, list
:param Y_coordinate: Uncorrected Y-coordinate of the satellite in
Jupiter's radii
:type Y_coordinate: float
:param Z_coordinate: Uncorrected Z-coordinate of the satellite in
Jupiter's radii
:type Z_coordinate: float
:returns: A tuple with the corrected rectangular coordinates (X, Y, Z)
of the satellite in Jupiter's radii
:rtype: tuple
:raises: TypeError if input values are wrong type
Calculate corrected rectangular Coordinates X, Y and Z in Jupiter's
radii for Io (1)
>>> R = 5.929892730360271
>>> i_sat = 1
>>> DELTA = 5.6611211815432645
>>> X_coordinate = -3.4489935969836503
>>> Y_coordinate = 0.21361563816963675
>>> Z_coordinate = -4.818966623735296
>>> io = JupiterMoons.correct_rectangular_positions(R, i_sat, DELTA, \
X_coordinate, Y_coordinate, Z_coordinate)
>>> print(io)
(-3.450168811390241, 0.21370246960509387, -4.818966623735296)
"""
# Check type
if not isinstance(i_sat, int):
raise TypeError("Invalid input types")
# Handle tuple or seperate values for input coordinates
if type(X_coordinate) in (list, tuple): # input type: tuple or list
X, Y, Z = X_coordinate
else: # input type: seperate values
X = X_coordinate
Y = Y_coordinate
Z = Z_coordinate
# Differential light-time correction:
# Correction factors for the satellites (index + 1 = No. of satellite)
K = [17295, 21819, 27558, 36548]
# Correct X-coordinate
X += (abs(Z) / K[i_sat - 1]) * sqrt(1 - (X / R) ** 2)
# Perspective effect correction:
# Compute correction factor
W = DELTA / (DELTA + (Z / 2095))
# Correct coordinates
X *= W
Y *= W
return X, Y, Z
[docs] @staticmethod
def check_phenomena(epoch, check_all=True, i_sat=0):
"""This method returns the perspective distance to any phenomena of all
satellites for the given epoch.
:param epoch: Epoch the calculations should be made for
:type epoch: :py:class:'Epoch'
:param check_all: Whether all satellites should be checked
:type check_all: bool
:param i_sat: Which satellite should be checked
:type i_sat: int
:returns: Distance to the satellite being ecclipsed, occulted in
penumbra
:rtype: tuple
:raises: TypeError if input values are wrong type
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> result_matrix = JupiterMoons.check_phenomena( \
utc_1992_12_16_00_00_00)
>>> print(result_matrix[0])
[-3.457757270630766, -2.553301264153796, 0.0]
>>> print(result_matrix[1])
[-7.44770945299594, -8.33419997337025, 0.0]
>>> print(result_matrix[2])
[-1.3572840767173413, -3.817302564886177, 0.0]
>>> print(result_matrix[3])
[-7.157430454898491, -11.373611474420906, 0.0]
>>> io_ecc_start_2021_02_12_14_19_14 = Epoch(2021, 2, 12.5966898148148)
>>> result_matrix = JupiterMoons.check_phenomena( \
io_ecc_start_2021_02_12_14_19_14)
>>> print([round(result_matrix[0][0], 10), round(result_matrix[0][ \
1], 10), round(result_matrix[0][2], 10)])
[1.192605868, 0.8560277162, 0.0]
>>> print([round(result_matrix[1][0], 10), round(result_matrix[1][ \
1], 10), round(result_matrix[1][2], 10)])
[-8.7397202369, -8.8930940921, 0.0]
>>> print([round(result_matrix[2][0], 10), round(result_matrix[2][ \
1], 10), round(result_matrix[2][2], 10)])
[14.0691219925, 13.8323491768, 0.0]
>>> print([round(result_matrix[3][0], 10), round(result_matrix[3][ \
1], 10), round(result_matrix[3][2], 10)])
[-2.9341209156, -3.9904598153, 0.0]
"""
# Check input type
if not isinstance(epoch, Epoch):
raise TypeError("Invalid input type")
# Calculate light-time delay
# DELTA, tau = JupiterMoons.calculate_delta(epoch)
# Calculate coordinates as seen from the Earth
Coords_Earth = JupiterMoons.rectangular_positions_jovian_equatorial(
epoch)
# Calculate coordinates as seen from the Sun
Coords_Sun = JupiterMoons.rectangular_positions_jovian_equatorial(
epoch, solar=True)
if check_all is True:
# Result matrix, where each rows is for a satellite
# Column 0: Occultation
# Column 1: Eclipse
# Column 2: No use
result_matrix = [[0.0, 0.0, 0.0],
[0.0, 0.0, 0.0],
[0.0, 0.0, 0.0],
[0.0, 0.0, 0.0]]
for i in range(len(result_matrix)):
# Coordinates for the iterated satellite
X = Coords_Earth[i][0]
Y = Coords_Earth[i][1]
Z = Coords_Earth[i][2]
X_0 = Coords_Sun[i][0]
Y_0 = Coords_Sun[i][1]
Z_0 = Coords_Sun[i][2]
# Check occultation
result_matrix[i][0] = JupiterMoons.check_occultation(X, Y, Z)
# Check eclipse
result_matrix[i][1] = JupiterMoons.check_eclipse(X_0, Y_0, Z_0)
return result_matrix
else:
return JupiterMoons.check_occultation(Coords_Earth[i_sat - 1][0],
Coords_Earth[i_sat - 1][0],
Coords_Earth[i_sat - 1][
0]), \
JupiterMoons.check_eclipse(
Coords_Sun[i_sat - 1][0], Coords_Sun[i_sat - 1][0],
Coords_Sun[i_sat - 1][0])
[docs] @staticmethod
def is_phenomena(epoch):
"""This method checks if the given coordinates correspond with any
satellite
phenomena. It returns the type of phenomena for all satellites.
:param epoch: Epoch the calculations should be made for
:type epoch: :py:class:'Epoch'
:returns: Result matrix for the four Galilean satellites
Row 0: Io Column 0: Occultation
Row 1: Europa Column 1: Eclipse
Row 2: Ganymede Column 2: No use
Row 3: Callisto
:rtype: tuple
:raises: TypeError if input values are wrong type
Calculation of result matrix for December 16 at 0h UTC
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> result_matrix = JupiterMoons.is_phenomena(utc_1992_12_16_00_00_00)
>>> print(result_matrix[0])
[False, False, False]
>>> print(result_matrix[1])
[False, False, False]
>>> print(result_matrix[2])
[False, False, False]
>>> print(result_matrix[3])
[False, False, False]
>>> io_ecc_start_2021_02_12_14_19_14 = Epoch(2021, 2, 12.5966898148148)
>>> result_matrix = JupiterMoons.is_phenomena( \
io_ecc_start_2021_02_12_14_19_14)
>>> print(result_matrix[0])
[False, True, False]
>>> print(result_matrix[1])
[False, False, False]
>>> print(result_matrix[2])
[False, False, False]
>>> print(result_matrix[3])
[False, False, False]
"""
# Get distance Matrix
dist_matrix = JupiterMoons.check_phenomena(epoch)
result_matrix = [[False, False, False],
[False, False, False],
[False, False, False],
[False, False, False]]
for row in range(len(result_matrix)):
for col in range(len(result_matrix[row]) - 1):
result_matrix[row][col] = (1 >= dist_matrix[row][col] >= 0)
return result_matrix
[docs] @staticmethod
def check_coordinates(X, Y):
"""This method checks if the given coordinates correspond with a
satellite
phenomena. It returns if the satellite with the given coordinates is
hidden
behind Jupiter or directly in front.
:param X: X-coordinate of the satellite in Jupiter's radii
:type X: float
:param Y: Y-coordinate of the satellite in Jupiter's radii
:type Y: float
:returns: Perspective distance to Jupiter's center in Jupiter's radii
:rtype: float
Calculation of the perspective distance of the planet Io to the
center of Jupiter
for December 16 at 0h UTC as seen from the Earth
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> result_matrix = \
JupiterMoons.rectangular_positions_jovian_equatorial( \
utc_1992_12_16_00_00_00, solar=False)
>>> io_radius_to_center_of_jupiter_earth = \
JupiterMoons.check_coordinates(result_matrix[0][0], result_matrix[ \
0][1])
>>> print(round(io_radius_to_center_of_jupiter_earth, 10))
3.4577572706
"""
# Accounting for elliptical Jupiter disk
Y *= 1.071374
return sqrt(X ** 2 + Y ** 2)
[docs] @staticmethod
def check_occultation(X=0, Y=0, Z=0, epoch=None, i_sat=None):
"""This method checks if the given coordinates or Epoch correspond
with a satellite being in occultation.
:param X: X-coordinate of the satellite in Jupiter's radii
:type X: float
:param Y: Y-coordinate of the satellite in Jupiter's radii
:type Y: float
:param Z: Z-coordinate of the satellite in Jupiter's radii
:type Z: float
:param epoch: Epoch that should be checked
:type epoch: :py:class:`Epoch`
:param i_sat: Index of the satellite (only for given Epoch)
:type i_sat: int
:returns: Perspective distance to center of Jupiter in Jupiter radii
as seen from the Earth (value of perspective distance is negative
when the satellite is closer to the Earth than Jupiter, otherwise
positive)
:rtype: float
:raises: TypeError if input values are wrong type
Calculation of the perspective distance of the planet Io
squareroot(X^2 + Y^2) to the center of Jupiter for December 16 at 0h
UTC as seen from the Earth
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> result_matrix = \
JupiterMoons.rectangular_positions_jovian_equatorial( \
utc_1992_12_16_00_00_00, solar=False)
>>> io_distance_to_center_of_jupiter_earthview = \
JupiterMoons.check_occultation(result_matrix[0][0], result_matrix[ \
0][1])
>>> print(round(io_distance_to_center_of_jupiter_earthview, 10))
-3.4577572706
"""
# Check if Epoch is given
if epoch is not None and i_sat is not None:
# Check types
if isinstance(epoch, Epoch) and isinstance(i_sat, int):
# Calculate coordinates for given Epoch as seen from the Earth
X, Y, Z = \
JupiterMoons.rectangular_positions_jovian_equatorial(
epoch)[
i_sat - 1]
else:
raise TypeError("Invalid input types")
# Check if satellite is more distant than Jupiter and distance to
# center
if Z > 0:
return JupiterMoons.check_coordinates(X, Y)
else:
return -1 * JupiterMoons.check_coordinates(X, Y)
[docs] @staticmethod
def check_eclipse(X_0=0, Y_0=0, Z_0=0, epoch=None, i_sat=None):
"""This method checks if the given coordinates or Epoch correspond
with a satellite being in eclipse.
:param X_0: X-coordinate of the satellite in Jupiter's radii
observed from the sun
:type X_0: float
:param Y_0: Y-coordinate of the satellite in Jupiter's radii
observed from the sun
:type Y_0: float
:param Z_0: Z-coordinate of the satellite in Jupiter's radii
observed from the sun
:type Z_0: float
:param epoch: Epoch that should be checked
:type epoch: :py:class:`Epoch`
:param i_sat: Index of the satellite (only for given Epoch)
:type i_sat: int
:returns: perspective distance to center of Jupiter in Jupiter radii
as seen from the Sun (value of perspective distance is negative
when the satellite is closer to the Sun than Jupiter, otherwise
positive)
:rtype: float
:raises: TypeError if input values are wrong type
Calculation of the Perspective distance of the planet Io
squareroot(X_0^2 + Y_0^2) to the center of Jupiter for December 16 at
0h UTC as seen from the Sun
>>> utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
>>> result_matrix = \
JupiterMoons.rectangular_positions_jovian_equatorial( \
utc_1992_12_16_00_00_00, solar=True)
>>> io_radius_to_center_of_jupiter_sunview = \
JupiterMoons.check_eclipse(result_matrix[0][0], result_matrix[0][1])
>>> print(round(io_radius_to_center_of_jupiter_sunview, 10))
-2.5533012642
"""
# Check if Epoch is given
if epoch is not None and i_sat is not None:
# Check types
if isinstance(epoch, Epoch) and isinstance(i_sat, int):
# Calculate coordinates for given Epoch as seen from the Sun
X_0, Y_0, Z_0 = \
JupiterMoons.rectangular_positions_jovian_equatorial(
epoch, solar=True)[i_sat - 1]
else:
raise TypeError("Invalid input types")
# Check if satellite is more distant than Jupiter and distance to
# center
if Z_0 > 0:
return JupiterMoons.check_coordinates(X_0, Y_0)
else:
return -1 * JupiterMoons.check_coordinates(X_0, Y_0)
def main():
# Let's define a small helper function
def print_me(msg, val):
print("{}: {}".format(msg, val))
# Let's show some uses of JupiterMoons functions
print("\n" + 35 * "*")
print("*** Use of JupiterMoons class")
print(35 * "*" + "\n")
# Lets compute the ascending node of Jupiter as well as the longitude of
# the node of
# the equator of Jupiter on the ecliptic (psi) .
utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
psi_corrected, OMEGA_ascending_node_jupiter = \
JupiterMoons.jupiter_system_angles(
utc_1992_12_16_00_00_00)
print("Ascending node of Jupiter: ", OMEGA_ascending_node_jupiter)
# 100.39249942976576
print(
"Longitude of the node of the equator of Jupiter on the ecliptic ("
"psi):",
psi_corrected)
# 317.1058009213959t
print("")
# Lets compute the corrected rectangular geocentric position of
# Jupiter's satellites
# for a given epoch, using the E5-theory.
utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
io, europa, ganymede, callisto = \
JupiterMoons.rectangular_positions_jovian_equatorial(
utc_1992_12_16_00_00_00)
print("Corrected rectangular geocentric position of Io [X, Y , Z]: ", io)
# (-3.450168811390241, 0.21370246960509387, -4.818966623735296)
print(
"Corrected rectangular geocentric position of Europa [X, Y , Z]: ",
europa)
# (7.441869121153001, 0.27524463479625677, -5.747104399729193)
print(
"Corrected rectangular geocentric position of Ganymede [X, Y , Z]: ",
ganymede)
# (1.201111684800708, 0.5899903274317162, -14.940581367576527)
print(
"Corrected rectangular geocentric position of Callisto [X, Y , Z]: ",
callisto)
# (7.071943240286434, 1.0289562923230684, -25.224137724734955)
print("")
# Lets compute the uncorrected rectangular geocentric position of
# Jupiter's satellites
# for a given epoch, using the E5-theory.
# So the effects of different light-time and perspective described in
# Pymeeus page 313 - 314 are neglected
utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
io_uncorrected, europa_uncorrected, ganymede_uncorrected, \
callisto_uncorrected = \
JupiterMoons.rectangular_positions_jovian_equatorial(
utc_1992_12_16_00_00_00, do_correction=False)
print(
"Uncorrected rectangular geocentric position of Io [X, Y , Z]: ",
io_uncorrected)
# (-3.4489935969836503, 0.21361563816963675, -4.818966623735296)
print(
"Uncorrected rectangular geocentric position of Europa [X, Y , Z]: ",
europa_uncorrected)
# (7.438101803124541, 0.2751112576349763, -5.747104399729193)
print(
"Uncorrected rectangular geocentric position of Ganymede [X, Y , Z]: ",
ganymede_uncorrected)
# (1.1990581804888616, 0.589247092847632, -14.940581367576527)
print(
"Uncorrected rectangular geocentric position of Callisto [X, Y , Z]: ",
callisto_uncorrected)
# (7.056237832405445, 1.0267678919629089, -25.224137724734955)
print("")
# Lets calculate the distance between Earth and Jupiter (DELTA) for a
# given epoch.
utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
delta, tau, l, b, r = JupiterMoons.calculate_delta(utc_1992_12_16_00_00_00)
print("Distance between Earth and Jupiter in AU: ", delta)
# 5.6611211815432645
print("Light-time from Earth to Jupiter in d (day): ", tau)
# 0.03269590898252075
print("")
# Lets calculate the perspective distance in Jupiter radii of all
# satellites
# for an eclipse of Io.
io_ecc_start_2021_02_12_14_19_14 = Epoch(2021, 2, 12.5966898148148)
result_matrix = JupiterMoons.check_phenomena(
io_ecc_start_2021_02_12_14_19_14)
# Row 0: Io Column 0: perspective distance as seen from the Earth
# Row 1: Europa Column 1: perspective distance as seen from the Sun
# Row 2: Ganymede Column 2: No use
# Row 3: Callisto
# print Row 0
print(
"(perspective distance of Io (Earth View), perspective distance of "
"Io (Sun view), No use): ")
print(result_matrix[0])
# [1.1926058680144362, 0.856027716233023, 0.0]
# print Row 1
print(
"(perspective distance of Europa (Earth View), perspective distance "
"of Europa (Sun view), No use): ")
print(result_matrix[1])
# [-8.739720236890856, -8.893094092124032, 0.0]
# print Row 2
print(
"(perspective distance of Ganymede (Earth View), perspective "
"distance of Ganymede (Sun view), No use): ")
print(result_matrix[2])
# [14.069121992481382, 13.8323491767871, 0.0]
# print Row 3
print(
"(perspective distance of Callisto (Earth View), perspective "
"distance of Callisto (Sun view), No use): ")
print(result_matrix[3])
# [-2.934134686233644, -3.9904786452498144, 0.0]
print("")
# Lets check if an eclipse or\and occultation for any of the four Galilean
# satellites is detected for a given epoch
io_ecc_start_2021_02_12_14_19_14 = Epoch(2021, 2, 12.5966898148148)
# Structure of result matrix
# Row 0: Io Column 0: Occultation True\False
# Row 1: Europa Column 1: Eclipse True\False
# Row 2: Ganymede Column 2: No use
# Row 3: Callisto
result_matrix = JupiterMoons.is_phenomena(io_ecc_start_2021_02_12_14_19_14)
# print Row 0
print("(Occultation of Io, Eclipse of Io, No use): ")
print(result_matrix[0])
# [False, True, False]
# print Row 1
print(" (Occultation of Europa, Eclipse of Europa, No use): ")
print(result_matrix[1])
# [False, False, False]
# print Row 2
print(" (Occultation of Ganymede, Eclipse of Gaymede, No use): ")
print(result_matrix[2])
# [False,False,False]
# print Row 3
print("(Occultation of Callisto, Eclipse of Callisto, No use): ")
print(result_matrix[3])
# [False,False,False]
print("")
# Calculation of the perspective distance ot the planet Io to the center
# of Jupiter
# for December 16 at 0h UTC as seen from the Sun
utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
result_matrix = JupiterMoons.rectangular_positions_jovian_equatorial(
utc_1992_12_16_00_00_00, solar=True)
io_radius_to_center_of_jupiter_sun = JupiterMoons.check_coordinates(
result_matrix[0][0], result_matrix[0][1])
print(
"Perspective distance of Io as seen from the Sun in Jupiter radii: ",
io_radius_to_center_of_jupiter_sun)
# 3.457757270630766
print("")
# Calculation of the perspective distance ot the planet Io to the center
# of Jupiter
# for December 16 at 0h UTC as seen from the Earth
utc_1992_12_16_00_00_00 = Epoch(1992, 12, 16, utc=True)
result_matrix = JupiterMoons.rectangular_positions_jovian_equatorial(
utc_1992_12_16_00_00_00, solar=False)
io_radius_to_center_of_jupiter_earth = JupiterMoons.check_coordinates(
result_matrix[0][0], result_matrix[0][1])
print(
"Perspective distance of Io as seen from the Earth in Jupiter radii: ",
io_radius_to_center_of_jupiter_earth)
# 2.553301264153796
if __name__ == "__main__":
main()