Equation 2: Increasing Planetary Mass

where:

x	Additional mass (kg)
d	Density of the additional mass (kg.m-3)
M	Original mass of the planet (kg)
r	Original planetary radius (m)
L	Luminosity of the star, sol: 3.86 x1026 (W)
Ro	For a planet: Minimum orbital radius of the planet (m)
	For a moon: Minimum orbital radius of the planet - Maximum orbital radius of the moon (m)

Note:
Including the exobase height will make the equation too complex, so it is not included at this time.
To solve the equation: use your own value of x until the equation is true.