Fade in chosen photo

Fade in chosen photo

Im using the code below for a gallery, where you click on the thumbnail and the large image appears on the right hand side. It work's great, but I would like the image to fade in instead of just appear and I can't seem to find where to enter the .fadeIn().

Thanks for any help
  2.       <script type="text/javascript"> //gallery
  3. $(document).ready(function(){
  4. //Swap Image on Click
  5. $("ul.thumb li a").click(function() {
  6. var mainImage = $(this).attr("href"); //Find Image Name
  7. $("#main_view img").attr({ src: mainImage });
  8. return false;
  9. });
  10. });
  11. </script>