Rocket is designing a backpack for astronauts. He loads it with tools until it is too heavy to lift.
"On the Moon, it would be easier," Raven says. "The pull is weaker there."
"How much weaker?" Rocket asks. "I need numbers to build with."
Nova projects the Moon beside Earth. "Here is a hint," she says. "The Moon's gravity is one sixth of Earth's. Can you share the weight into six equal parts?"
Rocket grabs a pencil. "Division," he says. "My favorite tool."
The Moon has gravity too. It pulls objects toward the Moon's center.
But the gravity on the surface of the Moon is only one sixth of Earth's.
That is why astronauts walking on the Moon seem to bounce.
When you weigh something, the scale measures how hard gravity pulls on it.
Weaker gravity means a smaller pull. So a backpack that weighs 60 pounds on Earth would weigh about 10 pounds on the Moon.
To find Moon weight, divide Earth weight by 6.
| Weight on Earth | Divide by 6 | Weight on the Moon |
|---|---|---|
| 60 pounds | 60 divided by 6 | 10 pounds |
| 18 pounds | 18 divided by 6 | 3 pounds |
| Statement | True or false? |
|---|---|
| The Moon has no gravity at all. | ? |
| Astronauts seem to bounce on the Moon because its gravity is weaker. | ? |
| A scale measures how hard gravity pulls on an object. | ? |
To find Moon weight, divide the Earth weight by 6.
A 30 pound bag on Earth weighs about 5 pounds on the Moon.
The bag is the same bag. Only gravity's pull changed.
Strong math today. Gravity is real, and it can be measured. Tomorrow you will test falling objects yourself.