101 body weights — how they read on other worlds
The amount of matter in a body never changes. What changes is the pull on it, and a scale measures that pull — one sixth of it on the Moon, two and a half times on Jupiter.
On Earth 70 kg
Mass is the matter you are made of; weight is the pull on it. Nobody loses matter by flying to the Moon — only the needle drops to one sixth. That is why physics measures weight in newtons rather than kilograms.
| Weight on other worlds | What the scale reads | Earth = 1 |
|---|---|---|
| the Sun | 1955.82 kg | ×27.94 |
| Mercury | 26.41 kg | ×0.377 |
| Venus | 63.31 kg | ×0.904 |
| Earth | 70 kg | ×1 |
| the Moon | 11.56 kg | ×0.165 |
| Mars | 26.55 kg | ×0.379 |
| Jupiter | 176.95 kg | ×2.528 |
| Saturn | 74.52 kg | ×1.065 |
| Uranus | 63.31 kg | ×0.904 |
| Neptune | 79.59 kg | ×1.137 |
| Pluto | 4.43 kg | ×0.063 |
Where the scale reads higher
Only four: the Sun, Jupiter, Saturn and Neptune. Saturn has eight times Earth’s mass yet only 6% more surface gravity — it is so puffed up that its surface sits far from the centre.
Jump height goes the other way
For the same push, the height you rise is inversely proportional to gravity. A 50 cm jump on Earth becomes over three metres on the Moon — and it does not depend on how much you weigh.
Some of these have no ground
Jupiter, Saturn, Uranus and Neptune have no solid ground; their figures are taken at the cloud tops. The Sun needs no explanation — nothing could stand there, so the number is arithmetic only.
From 30 to 130 kg
How to read this
- Scale reading = Earth weight × (that world’s gravity ÷ Earth’s gravity).
- Earth’s gravity is 9.80665 m/s², and every ratio here is measured against it.
- Force in newtons = mass × gravity. A 70 kg person feels about 686 N on Earth.
- Jump height is inversely proportional to gravity, so the Moon lifts you six times higher.
Frequently asked questions
Q. Do you actually lose weight on the Moon?
No. The matter in your body is unchanged; only the reading drops to a sixth. Come back to Earth and the scale is where it was.
Q. Why measure weight in newtons rather than kilograms?
Kilograms measure mass, and weight is a force. A bathroom scale shows kilograms only because Earth’s gravity is already divided out — take it to the Moon and it reads one sixth.
Q. Why is Saturn so close to Earth?
It has eight times the mass but is puffed up so far that its surface sits much further from the centre. Gravity falls off with the square of distance, so the two effects nearly cancel and only 6% is left.
Q. Could you stand on Jupiter?
No. There is no solid ground, so the figure here is taken at the cloud tops. Below that, pressure and temperature climb sharply.
Q. How high could you jump on the Moon?
About six times as high, since jump height is inversely proportional to gravity. A 50 cm jump on Earth clears three metres there.