"""Important Bodies.
Contains some predefined bodies of the Solar System:
* Sun (☉)
* Earth (♁)
* Moon (☾)
* Mercury (☿)
* Venus (♀)
* Mars (♂)
* Jupiter (♃)
* Saturn (♄)
* Uranus (⛢)
* Neptune (♆)
* Pluto (♇)
and a way to define new bodies (:py:class:`~Body` class).
Data references can be found in :py:mod:`~einsteinpy.constant`
"""
import astropy.units as u
from einsteinpy import constant
from einsteinpy.coordinates import CartesianDifferential
[docs]class Body:
"""
Class to create a generic Body
"""
@u.quantity_input(mass=u.kg, R=u.km)
def __init__(
self,
name="Generic Body",
mass=0 * u.kg,
R=0 * u.km,
differential=None,
a=0 * u.m,
q=0 * u.C,
parent=None,
):
"""
Parameters
----------
name : str
Name/ID of the body
mass : ~astropy.units.kg
Mass of the body
R : ~astropy.units
Radius of the body
differential : ~einsteinpy.coordinates, optional
Complete coordinates of the body
a : ~astropy.units.m, optional
Spin factor of massive body. Should be less than half of schwarzschild radius.
q : ~astropy.units.C, optional
Charge on the massive body
is_attractor : Bool, optional
To denote is this body is acting as attractor or not
parent : Body, optional
The parent object of the body.
"""
if differential:
if differential.system == "Cartesian":
self.pos_vec = [differential.x, differential.y, differential.z]
self.vel_vec = [differential.v_x, differential.v_y, differential.v_z]
else:
self.pos_vec = [differential.r, differential.theta, differential.phi]
self.vel_vec = [differential.v_r, differential.v_t, differential.v_p]
self.a = a
self.R = R
self.q = q
self.mass = mass
self.name = name
self.coordinates = differential
self.parent = parent
def __repr__(self):
return (
"'Body ( name: ({0}), mass: ({1}), radius: ({2}), coordinates: ({3}), spin factor: ({4}), charge: ({"
"5}) )'".format(
self.name, self.mass, self.R, self.coordinates, self.a, self.q
)
)
def __str__(self):
return (
"Body ( name: ({0}), mass: ({1}), radius: ({2}), coordinates: ({3}), spin factor: ({4}), charge: ({"
"5}) )".format(
self.name, self.mass, self.R, self.coordinates, self.a, self.q
)
)
class _Sun(Body):
def __init__(self):
parent = None
name = "Sun"
R = constant.R_sun
mass = constant.Solar_Mass
super(_Sun, self).__init__(name=name, mass=mass, R=R, parent=parent)
Sun = _Sun()
class _Earth(Body):
def __init__(self):
parent = Sun
name = "Earth"
R = 6731 * u.km
mass = 5.97219e24 * u.kg
super(_Earth, self).__init__(name=name, mass=mass, R=R, parent=parent)
Earth = _Earth()
