Why is one of my objects is not visible in the final rendering? I've been building a low-poly planet but for some reason when I hit render one of my objects is not visible. I have tried everything I can think of but nothing seems to make the object appear in my render. 

Tried adding a new camera, tried the 'clear restricted render' but I'm using mac and I can't get the prompt to show - unsure what shortcut/key it is on mac? 

If it is somehow relevant after I've clicked render and go to the compositing view I cannot see ANY nodes, completely blank.
you can check if relevant objects are enabled/disabled in render.
I usually prefer to show it in outliner like this:


click on filter icon and activate the button with camera icon





then you can see it in outliner and check if object is enabled/disabled for rendering


 

and since you are using modifiers you should check if render is enabled for modifier too (it is always the camera icon)