The Planet Quiz Show

Jupiter has the most gravity, while Mercury has the least gravity.

The surface gravity of a planet is a function of the amount of mass (matter) that the planet possesses and the diameter or size of the planet. The diameter of the planet is a more important consideration than its mass. That is why the most massive planets, which are also the largest planets, do not possess as much surface gravity as might be expected. Jupiter’s gravitational pull at its cloud tops is just over 2.5 times the surface gravity of Earth. Mercury’s gravitational pull is 37.4 percent of Earth’s surface gravity while Mars’s gravity, at 38 percent of Earth’s gravitational pull, is a close second. Put in a more precise way, the gravitational attraction at the surface of a planet is directly related to that planet’s mass and inversely related to the square of that planet’s radius.

            *gravitational attraction measured at cloud tops

What goes up must come down, even on Earth's moon. Astronaut John Young performs his famous flying salute of the American flag during the first EVA of Apollo 16, April 20, 1972. Notice how Young’s shadow disconnects between his boot and the lunar surface, proving that he is off the surface of the moon. A few seconds later, Young came down gently onto the moon’s regolith (lunar soil). The moon has only 1/6th the force of Earth’s gravity. NASA AS16-113-18340 photo...