English

Suisei no Gargantia: Meguru Kouro, Haruka

Japanese

翠星のガルガンティア～めぐる航路、遥か～

English

Gargantia on the Verdurous Planet: Far Beyond the Voyage

An announcement made at AnimeJapan 2014 revealed that a new 2-episode OVA for Suisei no Gargantia will be released with the first episode coming Fall 2014. The screening event for the first OVA was announced as well. More information on the OVA will be given at a later time.

(Source: MAL News)