During the Secession War, Jericho departed for Mission 161 to investigate the alien artifacts on planet Persephone and was accompanied by the USS Lexington. Commanded by Captain McKain, the Jericho was outfitted with an array of sensors and special instruments to be used to gather data on the alien installation.
The two ships departed for Persephone from the Eisenhauer orbital docks around Titan. Four months later, they arrived to Persephone and entered low orbit, the Jericho being 5000 meters behind Lexington as the scientist crew were prepared to deploy Ariadne.
The two ships were ambushed by the UNS Dharma. During the ensuing battle, Captain Steven Dayna asked McKain to abort the lander countdown and secure the ship and close up at 1km from the Lexington to be covered by their Close-In Combat System. Both ships were hit and Dayna plead for surrender. Commander Garrick accepted and ordered to deactivate the weapons systems and power out and gave 20 minutes to abandon both ships. Then according to Dayna's plans, the intership shuttle was detonated, destroying the UN ship and killing everyone on board, except a sole survivor.
The two ships were stranded in a .2 gee powered orbit 400 km above the planet as the survivor repaired the Lexington's reactor coolant system in order to save both ships. Later, he slaved Jerichos computer to that of the Lexingtons, jacked into Ariadnes on-board computer and deployed it automatically. Then he flew it over to the Lexingtons bay by the uplink, in order to descend to the planet and complete the mission.
After a petty officer of the Lexington warned the commanders about the ambush, he protected both ships and destroyed Dharma. Safe now, the scientists of Jericho descended the planet, explored and gathered data on the installation and attempted to find any exploitable technology. They also gathered samples and returned to Earth with the information.