The solar system at a glance
This reference gathers the key numbers for the eight planets and three notable dwarf planets: mass and surface gravity relative to Earth, equatorial radius, orbital period and confirmed moon count. A sortable view lets you rank them by any property, and a weight calculator shows what you would weigh on each world.
How it works
The bodies are ordered by your chosen property. The weight calculator applies the simple relation:
weight_elsewhere = your_Earth_weight × surface_gravity_relative_to_EarthSurface gravity relative to Earth ranges from about 0.06 on Pluto to 2.36
on Jupiter, so the same person can weigh a small fraction of their Earth weight
on a dwarf planet yet more than double it on a gas giant. Mass and gravity are
expressed with Earth set to 1 for easy comparison.
A quick comparison of the planets
Sorting by mass reveals a striking division: the inner rocky planets (Mercury, Venus, Earth, Mars) are all less than 1.1 Earth masses, while the outer gas and ice giants start at roughly 15 Earth masses (Uranus) and climb to 318 Earth masses for Jupiter. The two populations formed in different regions of the solar nebula and have fundamentally different compositions.
Sorting by surface gravity shows that, despite its enormous mass, Saturn’s lower average density means its surface gravity is surprisingly close to Earth’s — around 1.06 g. You would feel almost the same weight standing on Saturn (hypothetically on its cloud tops) as on Earth. Mars, meanwhile, has only about 0.38 g, which is why Mars colony planners consider its long-term effects on bone density and muscle.
Weight on other worlds — worked examples
For a person who weighs 70 kg on Earth (where g = 1.00):
| World | Surface gravity | Weight |
|---|---|---|
| Mercury | ~0.38 g | ~27 kg |
| Mars | ~0.38 g | ~27 kg |
| Venus | ~0.91 g | ~64 kg |
| Moon | ~0.17 g | ~12 kg |
| Jupiter | ~2.36 g | ~165 kg |
| Saturn | ~1.06 g | ~74 kg |
| Pluto (dwarf) | ~0.06 g | ~4 kg |
Note that Mercury and Mars have nearly identical surface gravities despite very different sizes — Mars is much larger but less dense.
Moon counts and why they change
Saturn currently leads all planets with over 140 confirmed moons, narrowly ahead of Jupiter. The reason these numbers keep rising is that small, irregular outer moons are hard to detect — each new sky survey with better instruments finds more. The counts here reflect data available at the time of this reference; current totals may be higher.
Tips and notes
- Mass and gravity are relative to Earth = 1; radius is in kilometres.
- Jupiter is the most massive planet at about 318 Earth masses.
- Your mass never changes — only your weight, which tracks local surface gravity.
- Moon counts rise over time as new small satellites are confirmed by surveys.
- Pluto, Ceres and Eris are dwarf planets, not full planets, under the IAU 2006 definition.