How does the calculation work?
Your “age on another planet” is simply how many orbits around the Sun that planet has completed since you were born.
planet_age = (days lived on Earth) ÷ (orbital period in days)
Since Mars takes 687 days to go around the Sun, you “age” almost 2× slower on Mars. On Mercury, which goes around in 88 days, your age is 4× higher!
Why are the periods different?
According to Kepler’s Laws: the farther from the Sun, the slower the orbit. Neptune, for example, is 30× farther from the Sun than Earth and takes 165 years to complete one orbit.
Orbital period of the planets
| Planet | Period (days) | In Earth years |
|---|---|---|
| ☿ Mercury | 88 | 0.24 |
| ♀ Venus | 224.7 | 0.62 |
| 🌍 Earth | 365.3 | 1.00 |
| ♂ Mars | 687 | 1.88 |
| ♃ Jupiter | 4,332.6 | 11.86 |
| ♄ Saturn | 10,759.2 | 29.46 |
| ♅ Uranus | 30,688.5 | 84.02 |
| ♆ Neptune | 60,182 | 164.77 |
| ⯓ Pluto | 90,560 | 247.94 |