If you're ever hanging out on Mercury, now you can find Tolkien there:
According to Tolkien's own writings, the half-elven seafarer Earendil (you know, Elrond's papa) carries the shining Silmaril on his brow as he crosses the skies. Now, the little bit of Mercury that we can see shining, chasing the sun, is Tolkien's vessel. He shines like a diamond ... explaining the rather bad pun in the title above.
More on why Mercury has craters named for artists on it can be found here.