1. During an Apollo lunar landing mission, the command module continued to orbit the Moon at an altitude of 100km. How long did it take to go around the Moon once? 2. T= 2(pi)(r^3/2) / root (GM) mass of moon = 7.35 X 10^22 radius of moon= 1.74 X 10^6 3. I think that is the correct equation, and I've tried plugging all the values in. I know that the radius will have the 100km (100,000m) added on to it...right?