The sun revolves around the center of mass of the Milky Way galaxy in an orbit that is approximately circular, of radius a ≈ 2.8 × 10¹⁷ km and velocity v ≈ 250 km/s. Use the result of Exercise 2 to estimate the mass of the portion of the Milky Way inside the sun’s orbit (place all of this mass at the center of the orbit).

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

Transcribed Image Text:

M = 3 (+7) () G