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**Kepler's Laws--What am I doing wrong here?**

**1. Homework Statement**

Io, a satellite of Jupiter, has an orbital period of 1.77 days and an orbital radius of 4.22 x 10^5km. From these data, determine the mass of Jupiter.

**2. Homework Equations**

T^2=(4(pi)^2/GM)r^3

**3. The Attempt at a Solution**

I converted the radius from km to meters and substituted all of the numbers to their variables. However, I still came up with the wrong answer. Please help me check my work, thanks!

Divided r^3 from both sides:

(1.77)^2/(4.22x10^8m)^3= 4(pi)^2/(6.673 x 10^-11)M

Multiplied universal gravitation constant with M(mass) on both sides:

(4.1688x10^-26)(6.673x10^-11)M=4(pi)^2

solved for M: M=4(pi)^2/ (2.78184 x 10^-36)

I came up with: 1.4192 x 10^37

The correct answer is: 1.90 x 10^27 kg

What am I doing wrong? Thanks!!