def gravitationalForce(mass1, mass2, distance):
    """assumes mass1 is a number, representing the mass of an object, in kilograms
    assumes mass2 is a number, representing the mass of another object, in kilograms
    assumes distance is a number, representing the distance between the objects, in meters
    """
    gravitational_constant = 6.673 * (10**-11)
    return gravitational_constant * mass1 * mass2 / (distance ** 2)