Q:  What is the semi-major axis a of the orbit of star SO-2?
           Express your answer in meters.


              a  =  1 x 10^(14) m        (approx)


  The period of this star's orbit is about 16 years.


  Q:  Convert the period P into seconds.


              P  =  (16 year) * (3.15 x 10^7 sec/year)

                 =   5 x 10^(8) s        (approx)



  Q:  Using Kepler's Third Law, calculate the mass of the object
            at the center of our Milky Way.


                               4 pi^2 * a^3
                 M(tot)  =   --------------
                                G * P^2


                         =   2.4 x 10^(36)  kg


                         =   1.2 x 10^6     solar masses