earth_shine

ssapy.compute.earth_shine(r_sat, r_earth, r_sun, radius, albedo, albedo_earth, albedo_back, area_panels)[source][source]

Calculate the fractional flux of sunlight reflected from the Earth to the satellite.

This function computes the flux of sunlight reflected from the Earth to the satellite, including contributions from the back surface of the satellite’s solar panels.

Parameters:

r_sat(n, 3) numpy.ndarray: Array of coordinates representing the position of the satellite.
r_earth(n, 3) numpy.ndarray: Array of coordinates representing the position of the Earth.
r_sun(n, 3) numpy.ndarray: Array of coordinates representing the position of the Sun.
radiusfloat: Radius of the satellite in meters.
albedofloat: Albedo of the satellite’s surface.
albedo_earthfloat: Albedo of the Earth.
albedo_backfloat: Albedo of the back surface of the satellite’s solar panels.
area_panelsfloat: Area of the satellite’s solar panels in square meters.

Returns:

dict: Dictionary containing the flux contributions from the Earth to the satellite: - ‘earth_bus’: Fraction of light reflected off the satellite’s bus from the Earth. - ‘earth_panels’: Fraction of light reflected off the satellite’s panels from the Earth.

Notes:

The function assumes that the solar panels are always facing the Sun and calculates flux based on the phase angle.
Flux contributions from the back surface of the solar panels are computed.

Example:

>>> r_sat = np.array([[1e7, 1e7, 1e7]])
>>> r_earth = np.array([[1.496e11, 0, 0]])
>>> r_sun = np.array([[0, 0, 0]])
>>> earth_shine(r_sat, r_earth, r_sun, radius=0.4, albedo=0.20, albedo_earth=0.30, albedo_back=0.50, area_panels=100)
{'earth_bus': array([...]), 'earth_panels': array([...])}