Mass

What Is Mass?

Mass is a way to measure how much stuff is in something. Think of a big teddy bear and a small teddy bear. The big one has more mass because it has more stuff inside it. Mass is different from weight. Your weight can change if you go to the Moon because the Moon has less gravity. But your mass stays the same everywhere — on Earth, the Moon, or even in space!

Measuring Mass

We measure mass in kilograms. A small apple might have a mass of about 1 kilogram. A big backpack might have a mass of 5 kilograms! Scientists use special tools to measure mass very exactly. Even tiny particles, like the ones that make up atoms, have mass.

Mass and Gravity

Mass helps create gravity. The more mass something has, the stronger its gravity pull. This is why the Sun can keep the planets moving around it. The Sun has a lot of mass, so its gravity is very strong. Without mass, there would be no gravity — and we would just float away into space!

Fun Facts About Mass

• Your mass is the same on Earth, the Moon, and even Mars. Only your weight changes.
• The kilogram is one of the most important units in science. It helps us measure everything from food to giant ships!
• Even the tiniest bits of matter, like atoms, have mass. Scientists use a special unit called the dalton to measure these tiny masses.