null new collider for raycast grabbing

I am trying to create a script that grabs an object when you press 'g'. I think the code I wrote should work, but I get "NullReferenceException: Object reference not set to an instance of an object Cameragrab.Update () (at Assets/Cameragrab.cs:24)" when I try to grab an object.

Here's the code:

 using UnityEngine;
 using System.Collections;
 
 public class Cameragrab : MonoBehaviour
 {
         // Use this for initialization
         void Start ()
         {
     
         }
     
         // Update is called once per frame
         void Update ()
         {
         GameObject held = new GameObject();
                 if (Input.GetKey ("g")) {
                         RaycastHit hit = new RaycastHit();
 
                         if (Physics.Raycast (transform.position, transform.forward, 5f)) {
                                 Debug.Log ("Touching");
                 if(hit.collider == null){
                     Debug.Log("Here");
                 }
                                 held = hit.collider.gameObject;
 
                                 hit.collider.gameObject.transform.parent = transform;
                                 hit.collider.gameObject.transform.position = transform.position - transform.forward;
                         }
                 } else if (held != null) {
                         held.transform.parent = null;
                         held = null;
                 }
         }
 }

It seems when I create the new hit raycast, it is null, as I receive the "Here" in my debug log when I press "g". Is this the problem? If not, what is? If it is, how do I fix it?