Io, a satellite of Jupiter, has an orbital period of 1.43 days and an orbital radius of 4.35X10^5 km. From this data, determine the mass of Jupiter. So step one: I cried. then I tried to use the equation: T^2=4(pi)^2/(GXMj) X R^3 thus (123552)^2= (39.478)/(6.672X10^-11)(Mj) X (4.34X10^5)^3 35161.29=(39.478)/(6.672X10^-11)(Mj) X (8.17465X10^16) Mj=1.3756X10^24 Apparently I was wrong... Anyone have any ideas what I did to mess this up?