```

T^2 = (4 * pi^2 / GM) * r^3

```

where:

* T is the orbital period (in seconds)

* G is the gravitational constant (6.674 × 10^-11 N m^2 kg^−2)

* M is the mass of the central body (in kilograms)

* r is the semi-major axis of the orbit (in meters)

This equation can be used to calculate the orbital period of any object orbiting the Sun, including planets, asteroids, and comets.