Calculating your weight on different planets is an example of how gravity's pull varies throughout the solar system.
The solar system's planets all have their own gravitational pull. Gravity can be a difficult concept for students to grasp because it is intangible and omnipresent, making it hard to demonstrate clearly. Science projects that deal with gravity and the planets are an effective method of teaching students how gravity works, both on Earth and elsewhere in our solar system.
About Gravity
Gravity is the force that pulls together everything you can physically touch, known as matter. The more matter an object has, the more gravity it has. This is why planets have so much gravitational pull; they are very large and dense. The term "mass" refers to the measurement of how much matter an object has. The more mass the object has, the more gravitational pull it exerts. Gravity's force is also affected by how close an object is to a gravitational pull. This rule of proximity explains why we stay on Earth instead of being sucked toward the sun, which has far more mass and, consequently, far more gravitational pull.
Study of Orbits
One of the most obvious examples of gravity at work in space is an orbit. Orbits are regular paths that an object regularly travels around another object. Orbits are determined by the gravity being exerted on an object by another object with more mass. This explains why the Earth repeatedly orbits around the sun, and why the moon orbits around the Earth. Orbits are circular or elliptical, and the object that is in orbit is often called a satellite. Satellites can be natural, like the moon, or made by humans, like a weather satellite or the orbiting human-made objects that make satellite TV and cellphones possible. To further explore orbits, draw a poster of the solar system and track the orbits of each planet and moon by drawing their orbit paths. You can find information on natural satellites, or moons, on the NASA website or in a scientific encyclopedia. Use this information to determine which planets have the most satellites and which have the least.
Your Weight in Outer Space
Because gravity dictates how much you weigh, determining your weight on other planets is an educational way to explore how gravity differs throughout the solar system. This project also helps kids practice their multiplication skills. Your weight on other planets is determined by your mass -- i.e., your weight on Earth -- multiplied by the gravity on a given planet. For example, if you weigh 100 pounds and Saturn's gravitational pull is 0.92, then your weight on Saturn is 92 pounds. Earth's gravity is represented by 1.0, Venus by 0.90, Mars by 0.38, Mercury by 0.38, Jupiter by 2.5, Neptune by 1.2, the moon by 0.17 and Uranus by 0.91. The sun's gravity is represented by 27.9. Use these values to calculate what your weight would be on each planet. Where would you weigh the most? Where would you weigh the least?
Comparative Weights
A way to help kids understand and discuss gravity is to compare the weights of household objects with what their weights would be on other planets. Think of a few objects to weigh or research, and calculate their weights on other planets. For example, a package of butter would weigh about 0.25 lbs. on the moon. An 8,000-lb. elephant would weigh 223,200 lbs. on the sun! Share your research by making a poster of your most interesting findings, with visuals such as clip art of the objects you weighed pasted beside each corresponding experiment.
Tags: gravitational pull, solar system, other planets, would weigh, your weight, more mass, object more
