Heart Lamp of Helseth Arborium
The hearts in these lamps, one of which resides in the bunk of Helseth Arborium, are from former captains and crew of The Due Return.
The preservation of the hearts began in the Doomsday Vault, when Cadmus O'Hare Faun II created the Heart Shrinker he made with Dr. Henry Helseth (a chemist who lives in the Doomsday Vault) for fun and to pass time. Cadmus O'Hare Faun II shrinks and preserves his first heart, Cadmus O'Hare's heart, following the latter's suicide after losing a game of Nostrovia with Cada Blue, thus losing his captainship to her as well.
The "heart shrinker" is nearby in the ship's archive.