An object's weight is a measure of the pull of gravity.

Mass

Mass is a measure of the amount of matter in an object.  Mass is a combination of the total number of atoms, and the type of atoms in an object.
  • ​​An object's mass does not change (unless you remove some!)​

Weight

An object's weight is a measure of the pull of gravity.
  • ​Weight CAN change depending on your location on Earth in the Solar System, or in the Universe.
  • As you travel away from the Earth's surface, your mass stays the same, but your weight reduces as gravitational pull decreases as you go farther out into space.

Mass vs. Weight

Your weight changes depending on where you are on Earth!  The gravitational pull of Earth on you can change slightly as you move around the surface of the Earth.  This is because the Earth is not a perfect sphere and your distance from Earth's center can change. Therefore, generally speaking your weight is lower on top of a mountain than at sea level!

Why does your Weight Change in the Universe?

 Your weight is a measure of the pull of gravity between you and the body (planet) you are standing on.  Your weight depends on the gravitational pull of the celestial object.  So the greater the gravity greater your weight.
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Notice the weight is so great on Jupiter due to its enormous mass!
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Click here to find out YOUR weight on other planets!

Weightlessness!

While astronauts may not weigh anything in space and can float around freely because there is no gravitational force to pull them down.  Their body shape and mass do not change as a result and they are weightless! This is also called zero-G​.
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Don't ask me why this dog is zero-G! IDK!
Video Guide:
  1. ​How high could you jump on different planets?
  2. What planet could YOU jump the highest on?

Topic Tips

  • Mass is a measure of how much matter something contains.
  • Weight is a measure of how strongly gravity pulls​ and does change depending on your location.

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