If you double your mass, gravity pulls on you twice as hard. If the planet you are standing on is twice as massive, gravity also pulls on you twice as hard. On the other hand, the farther you are from the center of the planet, the weaker the pull between the planet and your body. The force gets weaker quite rapidly. If you double your distance from the planet, the force is one-fourth. If you triple your separation, the force drops to one-ninth.
Ten times the distance, one-hundredth the force. See the pattern? The force drops off with the square of the distance. If we put this into an equation it would look like this:.
The two "M's" on top are your mass and the planet's mass. The "r" below is the distance from the center of the planet. The masses are in the numerator because the force gets bigger if they get bigger. The distance is in the denominator because the force gets smaller when the distance gets bigger.
Note that the force never becomes zero no matter how far you travel. No other planet in the Solar System has this property. Unlike Earth, Saturn does not have a surface on which a spacecraft could land. A spacecraft descending through the clouds of Saturn would encounter gases becoming hotter and denser until finally the spacecraft would be crushed and melted. Saturn rotates very rapidly - a day on Saturn is only 10 hours and 39 minutes long. Whether you are a science fiction fan, a space enthusiast or one of the millions who have watched astronauts gamboling about the moon's surface, you may have wondered how much you would weigh on other planets in the solar system.
Related: Would humans born on Mars grow taller than Earthlings? Weight is the force gravity exerts on an object due to its mass. Mass, roughly, measures an object's inertia, its resistance to being moved or stopped, once it's in motion.
Your mass remains constant across the universe except in certain cases discussed in special relativity , but that is another story , while your weight changes depending on the gravitational forces acting on you, which vary from planet to planet. Of course, that brings up the question of what we mean by "surface" when we're talking about "surface gravity".
Here on Earth, we have a solid surface at which to measure it, but planets like Saturn and Jupiter have no solid surface - they are gas giants. We have to pick a "surface. Now, if we're being really accurate about things, the gravity you'd feel at the "surface" of Saturn would actually depend on whether you were near the poles or the equator.
Everything we've told you so far is accurate for near the north or south poles of the planet. If you were to find a place to stand near the equator, however, you'd actually feel a little lighter, because Saturn's spin is enough to offset some of the pull of gravity through centrifugal force.
If you weigh lbs on Earth and lbs near Saturn's poles, you'd weigh closer to 91lbs near Saturn's equator. Incidentally, this also works for the Earth - if you weigh lbs at the North and South Poles, you'd weigh
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