Josh Baxter was the Communications Officer aboard the deep space mining vessel DSMO Marion. He was serving on the ship above LV178 in 2159 when the miners on the planet below stumbled upon a large number of Xenomorphs deep underground in the mines. The incident eventually led to the destruction of the Marion and the loss of all but one of its crew.
As well as operating the Marion's communications equipment, Baxter also ran a small bar, Baxter's Bar (more commonly known as BeeBee's), in the ship's recreation module. Baxter was killed on LV178 when a Xenomorph pulled him half-way out of a moving elevator, causing it to sever him in half.
Aboard the Marion
When not working at BeeBee's, Baxter was typically found on the bridge at the comms station. When the Samson and the Delilah fled LV178 with Xenomorphs on board, it was Baxter who attempted to contact their pilots, Jones and Keech, to ascertain the reason for their flight, learning of the creatures aboard the shuttles. After the catastrophic collision with the Delilah, it was Baxter's job to transmit Hoop's distress signal, a process made considerably harder by the destruction of the Marion's long-range antenna array.
When the surviving crew realised they needed the Samson to escape the doomed Marion and would therefore have to kill the Xenomorphs on board the shuttle, Baxter remained on the Marion's bridge with Lachance, both of whom were considered too valuable to endanger in a confrontation with the creatures, given their roles on the ship. Despite the fact one of the Xenomorphs boarded the Marion, Baxter and Lachance were not attacked, the Alien instead disappearing into the bowels of the ship.
Down to the surface
Baxter was wounded almost immediately on LV178, breaking an ankle when Ash sabotaged the lift carrying the survivors into the mine. Dr. Kasyanov splinted the injury as best she could, but Baxter still required doses of painkiller to control the pain. When the group discovered the derelict ship in the cavern at the bottom of the mine, Baxter's injury caused him to trip and fall, unintentionally firing his plasma torch and causing a cascade of molten rock that wounded Hoop.
As things deteriorated inside the derelict, with Sneddon being subdued by a Facehugger and Kasyanov being seriously wounded by acid, Hoop still refused to abandon his wounded comrades and the entire group managed to make it through the ship and back into the mines. However, as they attempted to escape the mine using its second elevator they were attacked again, and Baxter was dragged partway out of the rising cage. Despite attempts to save him, he was torn in half when the elevator passed a support beam, his legs and lower torso falling to the floor of the elevator car while his upper body fell with the Xenomorph that had been holding him.
As the 'manager' of BeeBee's, Baxter was popular amongst the crew of the Marion and the miners who spent their downtime there. Due to the relatively short supply of water on the vessel, Baxter had a tendency of rehydrating bar snacks in stale beer, a practice that the crew had come to accept and find humor in.