1. The problem statement, all variables and given/known data An astronaut arrives at a new planet, and gets out his simple device to determine the gravitational acceleration there. Prior to this arrival, he noted that the radius of the planet was 7040 km. If his 0.400-m-long pendulum has a period of 1.0 s, what is the mass of the planet? 2. Relevant equations T = 2pi * sqrt(L/g) 3. The attempt at a solution g = (4pi^2*(0.400))/1^2 = 15.79 m/2^2 I was given this equation as a hint, but I can't figure out where to go from here to get mass.