Every year, the Earth completes one orbit of the Sun and every year, you have a birthday! And during a year, the Earth rotates 365 times on its axis and we experience 365 sun rises and sun sets. But how old would you be in days or years on another planet?
Do the maths to find out! Then check it with our online calculator.
By the end of this activity you will:
- Have calculated how many Earth days old you are
- Used data and maths to work out how old you would be on another planet
- Have compared your ages on different planets in our Solar System
- Have calculated how many days old you would be on another planet
To complete this activity you will need:
- To watch the video on this page
- To complete the worksheet (click here to open the worksheet)
- The Planet Data Sheet (below)
- Some paper and a pen
- A calculator (optional)
Use the video above and the Planet Data Sheet below to complete the worksheet.
You can then check your answers using the age calculator.
Planet Data Sheet
| Facts and Figures | Mercury | Venus | Earth | Mars | Jupiter | Saturn | Uranus | Neptune |
|---|---|---|---|---|---|---|---|---|
| Orbital Distance (AU)a | 0.38 | 0.72 | 1.0 | 1.52 | 5.2 | 9.54 | 19.2 | 30.06 |
| Radius (KM) | 2,440 | 6,052 | 6,378 | 3,397 | 71,492 | 60,268 | 25,559 | 24,746 |
| Year Length (Earth Days) | 88 | 225 | 365.25 | 687 | 4,333 | 10,759 | 30,687 | 60,190 |
| Day Lengthb (Earth Days) | 176 | 117 | 1.0 | 1.03 | 0.41 | 0.43 | 0.75 | 0.67 |
a 1 AU (or Astronomical Unit) = 149,600,000 km and is the mean distance from the Earth to the Sun.
b Day lengths are sidereal days (time taken to rotate once) except for Mercury and Venus which are given as solar days (time from one sunrise to the next).