According to the official website, Bandai Visual announced that they will distribute Blu-rays containing the first two episodes of Suisei no Gargantia
at Anime Contents Expo (ACE) 2013 to be held on March 30th and 31st. A total of 8,000 copies will be distributed free to the visitors.
The first episode of the anime will be aired on April 7th on Tokyo MX TV.
Source: Gargantia official website