Annona is one of the Nomai who came to the Solar System via the Vessel. He was on board Escape Pod 2 (together with Rhus, Bur, Melorae and Coleus), which landed on Ember Twin. After settling down in the Sunless City he was involved in speculations about the Quantum Moon, hypothesizing about its macroscopic quantum mechanics and later helping build the Quantum Moon Locator on Ember Twin's pole.
Annona is credited as the discoverer of warp technology, having shared it with the rest of the Nomai species in times before his clan was stranded. The warp core that powered the Vessel is an example of his design, and it was thanks to his tutelage that Poke was able to re-create warp technology after Annona's death.