     @el.find("#frame-id-#{frame_idx}").closest("div").show()
 
   destroyFrames: ->
-    image.remove() for image in @el.find('.frame-image')
+    image.remove?() for image in @el.find('.frame-image')
 
   onClickInvert: ->
     @invert = !@invert

    @el.removeClass 'loading'

  removeElementsOfClass: (class_name) ->
    element?.remove() for element in [@el.find(class_name)...]

  evaluateAnnotations: (P_ref) ->
    xs = []


  showSummary: ->
    @resetMarkingSurfaces() # remove previous marks
    
    if @Subject.current.metadata.known_asteroids.length isnt 0
      @knownAsteroidMessage.show() 
