## Essential University Physics: Volume 1 (3rd Edition)

We need to consider the molar mass of $H_2$, which has a fairly low molar mass. Because of this, it takes a heavy planet to attract it. (After all, recall a gravitational force depends on the mass of both things, not just the mass of the planet.) Because it takes a stronger gravitational pull, it makes sense that Jupiter, which is over 300 times more massive than earth, has more $H_2$ around it than earth does.