Constants

Constants necessary to computations

All units are in SI

class beyond.constants.Body(name, mass, equatorial_radius, *, flattening=1, **kwargs)

Generic class for the description of physical characteristics of celestial body

property eccentricity

Eccentricity of the body

equatorial_radius

Equatorial radius of the celestial body

flattening

Flattening of the celestial body

mass

Mass of the celestial body

property mu

Standard gravitational parameter of the body

name

Name of the celestial body

polar_radius()

Polar radius of the body

propagate(date)

Gives the statevector of the celestial body

Warning

A propagator should be attached to this body, as there is none provided by default. This can be done by setting Body.propagator. See solarsystem or jpl and their respective get_body() functions.

Parameters

date (Date) –

Returns

Return type

StateVector

Raises

BeyondError – when no propagator is attached to the object

propagator

Propagator, not set by default

beyond.constants.Earth = <Body 'Earth'>

Earth physical characteristics

beyond.constants.G = 6.6740831e-11

Gravitational constant in m³.kg⁻¹.s⁻² or N.m².kg⁻²

beyond.constants.Mars = <Body 'Mars'>

Mars physical characteristics

beyond.constants.Moon = <Body 'Moon'>

Moon physical characteristics

beyond.constants.Sun = <Body 'Sun'>

Sun physical characteristics

beyond.constants.c = 299792458

Speed of light in m.s⁻¹

beyond.constants.g0 = 9.80665

Standard Earth gravity in m.s⁻²