Your weight on Callisto
A person who weighs 150 pounds on Earth weighs about 19 pounds on Callisto, because Callisto's surface gravity is 0.13 g. A person who weighs 70 kilograms on Earth weighs about 8.8 kilograms on Callisto.
Illustration computed from Callisto's measured and derived values, not a photograph.
What it’s like to stand here
Why your weight changes here
Callisto is almost exactly the size of Mercury, about 2,410 kilometres in radius against Mercury's 2,440, but its gravity is only a third as strong: about 13% of Earth's. The difference is what the two are made of. Gravity follows g = GM/r², and with nearly the same radius the only thing left to vary is mass. Callisto is a mix of rock and ice, less than twice as dense as water, while Mercury is dense iron and rock, so Callisto holds about a third of Mercury's mass and pulls about a third as hard. Your mass would be unchanged there. Jupiter adds nothing to your weight either: Callisto and everything on it fall around Jupiter together, so only Callisto's own pull reaches the scale.
Your weight on every world in the solar system
Every body gravityfinder carries, with its gravity relative to Earth’s and what you would weigh there. Type your weight in the calculator above and the table follows it. The four giants have no surface, so theirs is the pull at the cloud tops.
| World | Type | Gravity | Weight (lb) | Weight (kg) |
|---|---|---|---|---|
| Mercury | planet | 0.38× | 56.5 | 25.6 |
| Venus | planet | 0.90× | 136 | 61.6 |
| Earth | planet | 1.00× | 150 | 68 |
| Mars | planet | 0.38× | 56.7 | 25.7 |
| Jupitercloud tops | planet | 2.53× | 379 | 172 |
| Saturncloud tops | planet | 1.07× | 160 | 72.5 |
| Uranuscloud tops | planet | 0.90× | 136 | 61.5 |
| Neptunecloud tops | planet | 1.14× | 171 | 77.5 |
| Ceres | dwarf planet | 0.029× | 4.4 | 2 |
| Pluto | dwarf planet | 0.063× | 9.4 | 4.3 |
| The Moon | moon of Earth | 0.17× | 24.8 | 11.2 |
| Io | moon of Jupiter | 0.18× | 27.5 | 12.5 |
| Europa | moon of Jupiter | 0.13× | 20.1 | 9.1 |
| Ganymede | moon of Jupiter | 0.15× | 21.8 | 9.9 |
| Callisto | moon of Jupiter | 0.13× | 18.9 | 8.6 |
| Titan | moon of Saturn | 0.14× | 20.7 | 9.4 |
| Enceladus | moon of Saturn | 0.012× | 1.7 | 0.8 |
| Triton | moon of Neptune | 0.079× | 11.9 | 5.4 |
| Charon | moon of Pluto | 0.029× | 4.4 | 2 |
Worked example: the formula with Callisto's numbers
Surface gravity comes from Newton’s law of gravitation: g = G × M ÷ r², where G is the gravitational constant, M the body’s mass and r the distance from its centre to where you stand.
- G = 6.674 × 10⁻¹¹ m³ kg⁻¹ s⁻²
- M = 1.08 × 10²³ kg (Callisto's mass)
- r = 2,410 km = 2.41 × 10⁶ m (mean radius)
- g = 6.674 × 10⁻¹¹ × 1.08 × 10²³ ÷ (2.41 × 10⁶)² = 1.24 m/s²
Earth, through the same formula, gives 9.82 m/s². So Callisto pulls 1.24 ÷ 9.82 = 0.126 times as hard as Earth.
Your weight on Callisto is your Earth weight times that ratio: 150 lb × 0.126 = 18.9 lb, or about 19 pounds.
The exoplanets closest to Callisto's gravity
No exoplanet gravityfinder states a gravity for comes within 10% of Callisto's 0.13 g; these are the nearest. Each has a mass and size good enough for gravityfinder to state its surface gravity.
More about being on Callisto
If your children grew up herea playful thought experiment
Low gravity, 0.13 times Earth's. A child who grew up here could become strikingly tall and lightly built, about 1.5x taller than on Earth: a 5 ft 10 in adult could stand nearer 8 ft 10 in, with long limbs and slender bones.
- Bones
- Light and slender
- With little weight to carry, the growing skeleton lays down far less bone, the way astronauts' bones thin in months of low gravity.
- Heart
- Unhurried
- With less weight pulling blood down toward the feet, the heart has far less work to do.
- Movement
- Bounding and springy
- So little weight means each step would carry the body up and forward in long, floating strides.
A playful thought experiment from this world’s gravity, not a prediction about any real person. No human has ever grown up off Earth, so no one truly knows; the direction (taller in low gravity, shorter and stockier in high) follows how growing bodies respond to weight.
Hear how a voice sounds herea computed acoustic demoEXPERIMENTAL · just for fun
You would hear nothing at all.
With essentially no atmosphere, there is no medium to carry sound. You could shout into someone's helmet from an inch away and they would hear nothing: space is silent.
How long to get there with today’s craftCALCULATED
At the speed of the Parker Solar Probe, the fastest craft ever built, the trip to Callisto would take about 38 days; a real mission took the Juno probe just under 5 years to reach Jupiter's neighborhood.
See Callisto's full page for its orbit, size, sky and how to see it.
Common questions
How much would I weigh on Callisto?
A person who weighs 150 pounds on Earth weighs about 19 pounds on Callisto, because Callisto's surface gravity is 0.13 g. A person who weighs 70 kilograms on Earth weighs about 8.8 kilograms on Callisto.
What is the gravity on Callisto?
Callisto's surface gravity is about 1.24 m/s², 0.126 times Earth's (0.13 g). gravityfinder computes it from Callisto's mass and radius with g = GM/r².
What is the difference between mass and weight?
Mass is the amount of matter in you, and it is the same everywhere. Weight is the force gravity exerts on that mass. On Callisto your mass would be unchanged, but a scale would read 0.126 times what it reads on Earth, because gravity there is weaker.
How high could I jump on Callisto?
About 7.9 times as high as on Earth, because the same push from your legs works against 0.126 times the gravity. A 50 centimetre standing jump on Earth would carry you about 4.0 metres on Callisto, and you would stay in the air about 7.9 times as long.
Where in the solar system would you weigh the most and the least?
Of the worlds with ground to stand on, you would weigh the most on Earth (1.00 g) and the least on Enceladus (0.012 g), where a person who weighs 150 pounds on Earth would weigh about 1.7 pounds. The strongest pull of all is at Jupiter's cloud tops, 2.53 g, but there is nothing there to stand on.
Which exoplanets have gravity like Callisto's?
Of the exoplanets gravityfinder states a surface gravity for, Kepler-138 b (0.17 g), K2-138 f (0.19 g), Kepler-176 c (0.20 g) and Kepler-444 b (about 0.23 g) come closest to Callisto's 0.13 g. None is within 10%, so read these as the nearest, not a match.
Could people land on Callisto?
Of Jupiter's large moons it would be the least harmful to visit, because it orbits outside the most intense part of Jupiter's radiation belts, which is why mission studies have looked at it as a base. Its gravity, about an eighth of Earth's, would also make landing and taking off far easier than on Earth.
How do I calculate my weight on Callisto?
Multiply your Earth weight by 0.126, Callisto's gravity relative to Earth's. For 150 pounds that is 150 × 0.126 = about 19 pounds. The 0.126 comes from g = GM/r² with Callisto's mass and radius, divided by the same calculation for Earth.
Gravity computed by gravityfinder from Callisto's mass and radius in the NASA planetary fact sheets (gravity = mass ÷ radius², with Earth = 1). Measured mass.