Transform.RotateAround

function RotateAround (point : Vector3, axis : Vector3, angle : float) : void

Description

Rotates the transform about axis passing through point in world coordinates by angle degrees.

This modifies both the position and the rotation of the transform.

JavaScript
    function Update() {
// Spin the object around the world origin at 20 degrees/second.
transform.RotateAround (Vector3.zero, Vector3.up, 20 * Time.deltaTime);
}

using UnityEngine;
using System.Collections;

public class example : MonoBehaviour {
void Update() {
transform.RotateAround(Vector3.zero, Vector3.up, 20 * Time.deltaTime);
}
}

import UnityEngine
import System.Collections

class example(MonoBehaviour):

def Update():
transform.RotateAround(Vector3.zero, Vector3.up, (20 * Time.deltaTime))