Ginga no Uo Ursa Minor Blue
Genres: Award Winning, Fantasy
Type: OVA, Episodes: 1
Aired: May 21, 1993
Source: Unknown
Rating: PG - Children
Synopsis:
Urey is a boy who lives in a laboratory in a lake with an old man. One day they find a strange star in the Little Dipper. The stars are disappearing and the Little Dipper changes into a fish shape. To save stars, they begin to sail across the Milky Way to the place where the strange fish lives. 

(Source: AnimeNfo)