C# Non-Static Member Rigidbody2D.MovePosition

I'm trying to make a script where a 2dGameobject with the script attached rotates around another 2dGameobject called RotateAroundObject and if that Gameobject isn't near the RotateAroundObject then move towards RotateAroundObject's position. But I keep getting an error saying I need an object reference for accessing a non-static member. What exactly is wrong with my code and how do I fix this error? I'm fairly certain all the parameters are correct.

 using UnityEngine;
 using System.Collections;
 
 public class RotateAround : MonoBehaviour {
     public GameObject RotateAroundObject;
     // Use this for initialization
     void Start () {
     
     }
     
     // Update is called once per frame
     void Update () {
         if(Vector3.Distance( transform.position, RotateAroundObject.transform.position) < 1)
         {
             transform.RotateAround(RotateAroundObject.transform.position, Vector3.forward, 20 * Time.deltaTime);
         }
         else if(Vector3.Distance( transform.position, RotateAroundObject.transform.position) > 1)
         {
          Rigidbody2D.MovePosition(RotateAroundObject.transform.position);
         }
     }
 }