If we were to travel to other planets, one of the first things we would have to learn would be how to walk on its surface, because on the surface of different planets, we would be subject to differing levels of gravity. Some planets have a stronger gravity than Earth's, some have weaker. On a planet with a weaker gravity, we would be able to carry more mass and jump higher. (Look Ma! I'm Superman!) On a planet with a stronger gravity, we might be forced to our knees by just our own weight. (ACK! Kryptonite!)
To calculate the surface gravities of varying planets, we can use the following equation, which is the simplified form of Newton's gravitational law :
The surface gravity (a) on a planet is equal to the Universal Gravitational Constant (G) multiplied by the planet's mass (M), divided by the square of planet's radius (r).
Different planets have different masses and radii. Thus, their surface gravities vary. By knowing the mass and the radius of a planet, we can calculate its surface gravity. The table below lists the results of our calculations.
Calculated Surface Gravities of Planets in our Solar System
|Surface Gravity *||0.35||0.91||1||0.39||2.63||1.17||0.94||1.06||0.07|