The series' hero. The 13-year-old biological son of Renton Thurston and Eureka, technically making him Ao Thurston; he resembles his father during his younger days, but with the hair, eye, and skin color of his mother. His mother one day fell from a clear sky into a bay in Iwato Jima, before giving birth to Ao sometime later. After Eureka was handed over to the American Armed Forces ten years ago, as the islanders believe her and Ao's presence angered their local deity the "Sea Colossus" with the appearance of Scub Coral, Ao ended up in the care of his mother's only friend Toshio Fukai. Ao discovers the RA272 Nirvash after he unintentionally retrieves his mother's bracelet from Gazelle who was smuggling it for the Japanese Army, and then Gazelle gets him to pilot the IFO, both named the Nirvash by Eureka and created by Renton. Ostracized by the villagers and targeted by the armies of several countries, Ao decides to join Team Pied Piper, hoping to find her. As the son of a human and a Coralian, he has been shown to possess a sort of psychic insight involving secrets, and the ability to see Trapar particles with his naked eyes.

(Source: Wikipedia)

The story is set on Okinawa's isolated island of Iwado, which has seen a growing movement advocating a return to an autonomous government. Ao Fukai, a 12-year-old boy with a missing father, lives on the island with an old doctor named Toshio and is about to enter middle school. Ao's mother was taken away a decade ago by unknown individuals. Naru Arata, Ao's 12-year-old childhood friend and the story's heroine, lives with her father, older sister, and grandmother. She has a "Yuta" power awakened within her due to an incident when she was young. A mysterious entity called "Secret" suddenly appears and launches an attack on the Scub Coral lifeform on the island. Ao launches a certain military FP called "Nirvash" aboard a Japanese military transport in his fervent desire to protect the island. 
(Source: FUNimation)

An original video anime, released on Blu-ray in a combined Hybrid Disc that also hold an Eureka Seven AO game for the PlayStation 3. 
The OVA is set between episodes eight and nine of the series.

Manga sequel to the Eureka Seven anime series. The story centers around a boy named Ao who "sets 'destiny' in motion again when he holds the 'power'". 
(Source: Anime News Network)

A short anime series that describes the everyday life of Ao and other Eureka Seven Ao characters.

Spin-off set in the same world as Eureka Seven AO, following the adventures of heroine Yuna Maltan.