A very captivating animation above, created by Dr. James O’Donoghue, a Planetary Astronomer at JAXA (Japan Aerospace Exploration Agency), shows a ball dropping from 1000 meters to the surface of each object, assuming no air resistance. This should give an idea for the pull you would feel on each object.
As apparent in the animation, it is surprising to see large planets having a weak pull comparable to smaller ones at the surface, for example Uranus pulls the ball down slower than at Earth! Why? Because the low average density of Uranus puts the surface far away from the majority of the mass. Similarly, Mars is nearly twice the mass of Mercury, but you can see the surface gravity is actually the same... this indicates that Mercury is much denser than Mars.
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