Phobos is a moon of Mars. Present in the First System, it was the site of a Conjoiner Nest during the 23rd Century, and the base of the shipyard in which the Conjoiners first ship, the Sandra Voi, was built and launched from.
History
Pre-Conjoiner
Phobos was involved in at least one interplanetary war, as it held a nest of autonomous mechanical worms during the 23rd Century. Although the Coalition for Neural Purity attempted to irradiate the worms, they were unsuccessful.
Use as a Conjoiner Base and Shipyard
Between the beginning of hostilities between baseline humanity - specifically the Coalition of Neural Purity - and the Conjoiners, and the beginning of the war between the two parties, a base was set up on Phobos. The base was also the target of a large mass driver that was used to evacuate the Conjoiner Nest on Mars, and also a shipyard, where the first interplanetary Conjoiner Drive was built and used in the function of the first starship, eventually named the Sandra Voi, after the recently deceased Demarchist of that name.