Ganymede, one of Jupiters moons discovered by Galileo, has an orbital period of 7.154 days and a

Question:

Ganymede, one of Jupiter’s moons discovered by Galileo, has an orbital period of 7.154 days and a semimajor axis of 1.07 × 10⁹m. Use Exercise 2 to estimate the mass of Jupiter.

Data From Exercise 2

Using Kepler’s Third Law, show that if a planet revolves around a star with period T and semimajor axis a, then the mass of the star is M = 3 (+7) () G