我在模拟两个物体间的引力我的星星和我的行星
但是它们会受到FPS的影响，随着我的FPS上升和下降，行星会变得越来越快。
我可以把Time.deltaTime放在哪里来解决这个问题？

using System.Collections;
    using System.Collections.Generic;
    using UnityEngine;
    
    public class Attractor : MonoBehaviour {
    
        const float G = 667.4f;
        public Rigidbody star;
        public Rigidbody planet;
        
        void Update(){
            Vector3 direction = star.position - planet.position;
            float distance = direction.magnitude;
    
            if (distance == 0f)
                return;
    
            float forceMagnitude = G * (star.mass * planet.mass) / Mathf.Pow(distance, 2);
            Vector3 force = direction.normalized * forceMagnitude;
    
            planet.AddForce(force);
        }
    }