Code: 360 Video

using UnityEngine;
using System.Collections;

public class InvertObjectNormals : MonoBehaviour 
{

    public GameObject SferaPanoramica;

    void Awake()
    {

    InvertSphere();
    }

    void InvertSphere()
    {
        Vector3[] normals = SferaPanoramica.GetComponent<MeshFilter>().sharedMesh.normals;
        for(int i = 0; i < normals.Length; i++)
        {
            normals[i] = -normals[i];
        }
        SferaPanoramica.GetComponent<MeshFilter>().sharedMesh.normals = normals;

        int[] triangles = SferaPanoramica.GetComponent<MeshFilter>().sharedMesh.triangles;

        for (int i = 0; i < triangles.Length; i+=3)
        {
            int t = triangles[i];
            triangles[i] = triangles[i + 2];
            triangles[i + 2] = t;

        }           

            SferaPanoramica.GetComponent<MeshFilter>().sharedMesh.triangles= triangles;
    }
    // Use this for initialization
    void Start () {

    }

    // Update is called once per frame
    void Update () {

    }
}




Attribution: https://stackoverflow.com/questions/36423846/flip-normals-in-unity-3d-spheres