This is an outtake ship found in the Derelicts section of the homeworld.big file that has texture maps and stats, but no geometry.

Look familiar? If you're a fan of the Aliens movies, it should. This is the lifeboat shuttle Narcissus, which Ripley used to escape the Nostromo after she set it to self-destruct. It appeared in the first and second Aliens movies.

What this ship is doing in Homeworld is unknown. Perhaps it was going to be a cute little Easter Egg floating about the Karos Graveyard, but was omitted (either because of time constraints or copyright concerns).

The lifeboat also appears in a Cataclysm cutscene, floating amonst the debris in the aftermath of a battle between Hiigaran and Imperialist Taiidan forces.