SLUM = 3.846e33 # ergs / s
SRAD = 6.957e+10 # cm
SMASS = 1.989e+33 # g
BDLUM = 1/100_000 # L/Lsolar
BDTEMP = 1000 # K
BDRAD = 1.001e+10 # cm
sb = 5.670374419e-5 # cgs
kb =  1.3807e-16#  cm2 g s-2 K-1 (cgs
BDATMMFRAC = 0.00001  #0.000001
G = 6.67430e-8 # cgs