Two astronauts are trying to figure out the mass of Mercury and the mass of Neptune. The astronauts decide to hit a 142 g ball with a bat on each planet and see how far it goes. They know the radius of mercury is 2,440 km and the radius of Neptune is 24,622 km. On mercury one astronaut hits the ball with a force of 52n over .1 seconds at a 40 degrees and it travels 700m. The second astronaut hits the ball with the same force at the same angle on Neptune and it travels 100m. What is the mass of the two planets? For the planet problem, I attempted to use the formula to find the gravity but need the mass of the planet. Then I attempted to find the mass but need the gravity. I don't even know where to start.