The details of the spacecraft aren't discussed in detail, but it was only capable of interplanetary flight in the vacuum of space, and among the larger ships in the hangar complement of the Nostalgia, with a carrying capacity of 2000 people. The capacity and capabilities of the ship are explicitly discussed by Ilia Volyova and Ana Khouri while they plan their evacuation of the refugees from an Inhibitor-threatened Resurgam. The ship type is presumably also used for the evacuation from the surface, once the whole effort is in motion.
The name of this ship type is, of course, somewhat conjectural, as the vessel is not described in any great detail. (Presumably, it is similar to other larger civilian ships, including freighters and in-system passenger ships used by the Demarchists or the Ultranauts.)