You can discover how to lose weight — or gain it — with the help of this activity.
First, click on either 'UP' or 'DOWN' to select your weight on Earth. Next, click and drag the astronaut to the right or to the left to each of the other planets.
What happens to your weight when you reach the surface of another planet?
Travel to each planet in the solar system. Where do you have the least weight? Where do you have the most weight?
Your weight is a measure of the force of gravity (g-force) pulling your body towards the planet. The g-force depends on three things — the mass of your body, the mass of the planet and the distance between your body and the centre of the planet. These three things have been used to calculate your weight when you stand on the surfaces of different planets.
If the g-force is 1.0 on the surface of Earth, the g-forces on the surfaces of the planets are:
On some of these planets, it would be difficult to weigh yourself. On planets made of gases (Jupiter, Saturn, Uranus and Neptune), you would not be able to stand on the surface! Instead you would be pulled through the gases towards the centre of the planet!
Sometimes people use the words 'mass' and 'weight' as if they are the same thing. Scientists define these differently.
A scientist defines your 'mass' as a measure of the amount of matter in your body. It is measured in kilograms (kg). Your mass does not change as you move from planet to planet.
A scientist defines your 'weight' as a measure of the force of gravity pulling your body towards the planet. Your weight becomes less as you move further from the centre of the planet. Your weight increases if you travel to a planet which has more mass (such as Jupiter). Scientists measure weight in newtons (N). A kilogram mass on the surface of Earth weighs almost 10 N. The same mass on Jupiter weighs 10 x 2.6 = 26 N because of the 2.6 g-force on Jupiter.
This activity was created when Neptune was further from the Sun than Pluto (between 1979 and 1999). Pluto has again become the furthest planet from the Sun and will continue to be for 228 years!