import numpy as np
import matplotlib.pyplot as plt
= 6.6743e-11 # N m2 kg-2; Newton's Constant
G = 1.380649e-23 # J/K; Boltzmann's Constant
k_B = 1.67262192e-27 # kg; proton mass
m_p
= 1.9884e30 # kg
M_sun = 6.957e8 # m
R_sun = 5780 # effective temperature, K Teff_sun
Notes
We will be using Python for computation in this book: in every case, we will be using the same fundamental constants in SI units, and the same imports of basic Python libraries: