Star of Eärendil - After Eärendil had traveled to Valinor, he could never go back to Middle Earth.

 

"Mandos spoke concerning his fate: 'Shall mortal Man step living upon the Undying Lands, and yet live?'" ~The Silmarillion, chap. 24 (Of the Voyage of Eärendil)

 

But as Eärendil was half-Elf, he was not simply a mortal Man.  So another of the Valar spoke on his behalf.

 

"But Ulmo said: 'For this he was born into the world.  And say unto me: whether is he Eärendil Tour's son of the line of Hador, or the son of Idril, Turgon's daughter, of the Elven-house of Finwë?'" ~The Silmarillion, chap. 24 (Of the Voyage of Eärendil)

 

Because he was neither fully Man nor fully Elf, and therefore could neither stay in Valinor nor return to Middle Earth, he was given a new domain in which to roam.

 

"But they took Vingilot (his ship), and hallowed it, and bore it away through Valinor to the uttermost rim of the world, and there it passed through the Door of Night and was lifted up even into the oceans of heaven,

 

"Now fair and marvellous was that vessel made, and it was filled with a wavering flame, pure and bright; and Eärendil the Mariner sat at the helm, glistening with dust of elven-gems, and the Silmaril was bound upon his brow.  For he journeyed in that ship, even into the starless voids; but most often was he seen at morning or at evening, glimmering in sunrise or sunset..." ~The Silmarillion, chap. 24 (Of the Voyage of Eärendil)

 

And his light was seen from Middle Earth even into the end of the Third Age.

 

"Eärendil, the Evening Star, most beloved of the Elves, shown clear above." ~The Fellowship of the Ring, Book II, chap. 7 (The Mirror of Galadriel)