from __future__ import division, print_function
from vpython import *

# Setup: constants
G =  6.67e-11      # universal gravitation constant
mcraft = 15.0e3   #  mass of spacecraft in kg
mplanet = 6.0e24  #  mass of planet in kg 

planet = sphere(pos=vector(0,0,0), radius=6.4e6, color=color.red)