Thanagarians of the Polaris Solar System had achieved tremednous leaps in technology beyond that of their peers on Earth-One, and yet they lacked expertise in law enforcement.. Hence, officers Katar and Shayera Hol journeyed there aboard an advance Star Cruiser to learn more about such techniques as Hawkman and Hawkgirl. This became their home away from home. On Earth-Two, Hawkman and his wife hadn't come from Thanagar-Two, and thus had no access to such technology. That is, until scientist Elwood Napier devised such a vessel employing a gravity drive which the Featured Fury and his Justice Society allies used to stop an alien invasion of the "Green Heads" from their base on Mars. The Justice League themselves more than once used Katar's vessel to stem off invasions such as that by the Martians of J'onn J'onzz world.
What became of the Star Cruiser that Carter Hall piloted, on that case with his Society allies, is unknown. No doubt he and his fellow All-Stars kept this vehicle in reserve in case of a future need. Perhaps .refabricated as teh JSA Sky-Rocket which the Society used to reach Brain Wave's satellite decades later.. Katar would continue to use his own cruiser to shuttle back-and-forth between his adopted and home worlds.