def get_moons_for_planet(planet, delta_JD=0. | units.day):
"""
The Earth's moon
as for JD = 2457099.500000000 = A.D. 2015-Mar-18 00:00:00.0000 (CT)
https://ssd.jpl.nasa.gov/?sat_elem
"""
data = numpy.array([tuple(entry) for entry in _lunar_data],
dtype=[('planet_name', 'S10'), ('name', 'S10'),
('mass', '<f8'), ('radius', '<f8'),
('semimajor_axis', '<f8'),
('eccentricity', '<f8'),
('argument_of_peri', '<f8'),
('mean_anomaly', '<f8'), ('inclination', '<f8'),
('longitude_oan', '<f8')])
moon_data = data[data['planet_name'] == planet.name.encode('UTF-8')]
print("Planet=", planet.name, "moon=", moon_data["name"])
moons = Particles()
if len(moon_data["name"]):
print(len(moon_data["name"]))
for moon in moon_data:
#Ignore the moon for now, because it's complicated
if planet.name == "EarthMoon":
planet.mass -= moon["mass"] * 1.e+16 | units.kg
planet.name = "Earth"
#print moon
r, v = get_position(planet.mass,
moon["mass"] * 1.e+16 | units.kg,
moon["eccentricity"],
moon["semimajor_axis"] | units.km,
numpy.deg2rad(moon["mean_anomaly"]),
numpy.deg2rad(moon["inclination"]),
numpy.deg2rad(moon["longitude_oan"]),
numpy.deg2rad(moon["argument_of_peri"]),
delta_t=delta_JD)
single_moon = Particle()
single_moon.type = "moon"
single_moon.name = moon["name"]
single_moon.mass = moon["mass"] * 1.e+16 | units.kg
single_moon.hostname = moon["planet_name"]
single_moon.radius = moon["radius"] | units.km
single_moon.position = r
single_moon.position += planet.position
single_moon.velocity = v
single_moon.velocity += planet.velocity
moons.add_particle(single_moon)
return moons
def get_moons_for_planet(planet, delta_JD=0.|units.day):
"""
The Earth's moon
as for JD = 2457099.500000000 = A.D. 2015-Mar-18 00:00:00.0000 (CT)
https://ssd.jpl.nasa.gov/?sat_elem
"""
data = numpy.array([tuple(entry) for entry in _lunar_data],
dtype=[('planet_name','S10'), ('name','S10'),
('mass','<f8'), ('radius','<f8'), ('semimajor_axis','<f8'),
('eccentricity','<f8'), ('argument_of_peri','<f8'),
('mean_anomaly','<f8'), ('inclination','<f8'), ('longitude_oan','<f8')])
moon_data = data[data['planet_name']==planet.name]
print "Planet=", planet.name, "moon=", moon_data["name"]
moons = Particles()
if len(moon_data["name"]):
print len(moon_data["name"])
for moon in moon_data:
#print moon
r, v = get_position(planet.mass,
moon["mass"] * 1.e+16 | units.kg,
moon["eccentricity"],
moon["semimajor_axis"]|units.km,
numpy.deg2rad(moon["mean_anomaly"]),
numpy.deg2rad(moon["inclination"]),
numpy.deg2rad(moon["longitude_oan"]),
numpy.deg2rad(moon["argument_of_peri"]),
delta_t=delta_JD)
single_moon = Particle()
single_moon.type = "moon"
single_moon.name = moon["name"]
single_moon.mass = moon["mass"] * 1.e+16 | units.kg
single_moon.hostname = moon["planet_name"]
single_moon.radius = moon["radius"] | units.km
single_moon.position = r
single_moon.position += planet.position
single_moon.velocity = v
single_moon.velocity += planet.velocity
moons.add_particle(single_moon)
return moons
