private void btnBack_Click(object sender, RoutedEventArgs e)
        {
            var missionWindow = new MissionControl(); //create your new form.

            missionWindow.Show();                     //show the new form.
            this.Close();
        }
        private void CreateNewButton_Click(object sender, RoutedEventArgs e)
        {
            var missionControlSys = new MissionControl(); //create your new form.

            missionControlSys.Show();                     //show the new form.
            this.Close();
        }
        private void btnAddSpacecraft_Click(object sender, RoutedEventArgs e)
        {
            MissionControl mControl = new MissionControl();

            if (txtSpacecraftName.Text != "" && txtOrbitRadius.Text != "" && txtPayloadName.Text != "" && comboPayload.SelectedItem.ToString() != "Select")
            {
                string  vehicleName = txtSpacecraftName.Text;
                int     orbitRadius = Convert.ToInt32(txtOrbitRadius.Text);
                string  payloadName = txtPayloadName.Text;
                string  typePayload = comboPayload.SelectedItem.ToString();
                Payload newPayload  = new Payload(payloadName, typePayload);
                Vehicle newVehicle  = new Vehicle(vehicleName, orbitRadius, newPayload);
                MainWindow.AllSpacecrafts.Add(vehicleName, newVehicle);



                mControl.comboNewSpacecrafts.Items.Add(txtSpacecraftName.Text);
                mControl.listNonActiveSpacecrafts.Items.Add(txtSpacecraftName.Text);
                MainWindow.NonActiveSpacecrafts.Add(txtSpacecraftName.Text);
                txtSpacecraftName.Text = "";
            }
            else
            {
                MessageBox.Show("All fields required !");
            }

            MessageBox.Show("Spacecraft and Payload Added to Queue");

            mControl.UpdateData();
            var missionWindow = new MissionControl(); //create your new form.

            missionWindow.Show();                     //show the new form.
            this.Close();
        }