Missionaries plying the yawning gulf between stars have to overcome two problems. First, yinrih cannot lose consciousness without dying. Second, faster than light travel is as yet impossible. While yinrih live over 700 Earth years on average, that's still not long enough to survive most interstellar missions, even at the quasiluminal speeds attainable by Claravian womb ships.

The solution is to suspend the missionary's metabolism while keeping the brain active through Science™. But this presents a third problem. In metabolic suspension, the mind is quickly driven mad by the lack of sensation. This is solved through the Simulacrum, a Matrix-like artificial reality presented to the missionary to keep the mind sane. Subjective time perception is also accelerated to make the journey seem to pass in a few weeks rather than centuries or millennia.

But this solution, too, creates its own issues. Namely the Voice. The Voice is a phenomenon manifesting as an intrusive train of thought attempting to convince the suspended person that the Simulacrum is reality, the only reality. Missionaries who give in to the Voice are said to have dissociated. So we're left with two undesirable ends of a spectrum. If the Simulacrum lacks verisimilitude the mind is driven mad, but the more realistic the Sim is, the stronger the Voice becomes. Total dissociation is next to impossible to reverse, and even if the victim is made aware of the true nature of the world they perceive, they're often too neurologically dependent on the Sim to survive outside it. Suspended missionaries undertake a regime of prayer and meditation to keep their minds anchored in reality.

Suspended missionaries can still interact with the outside world. There is a spartan operating system environment that missionaries can access outside the Sim. Here time flows normally and the systems of the womb ship can be accessed, including an ansible to receive FTL communications from mission control as well as remotely operated robots to repair and replace worn-out components during the journey.

The capsule is completely flooded with neurogel, which surrounds the suspended missionary, cushioning them against high G-forces and creating a link between the brain and the ship's systems without any implants, indeed without having to shave one's fur. The missionary's lungs and digestive tract are also completely filled with neurogel, further cushioning them and providing a liquid breathing medium for when their metabolism starts up again but they haven't yet left the capsule.

The posture of the physical body is significant. It is a pose often assumed by mystics in contemplative prayer. It is not known if this posture was necessitated by the nature of the suspension capsule, and was later emulated by the faithful, or if the designers of the first suspension capsules were accommodating preexisting devotional practice.

Firefly the Apostate is permanently sealed in a modified suspension capsule called the Eternal Womb. He lapsed during a failed missionary journey, his companions were killed (some say at his own paws) and, lacking the faith to resist the Voice, he dissociated, becoming dependent on the capsule to survive, even after regaining mental awareness. The fact that the leader of the militantly atheistic Partisans is forever frozen in serene meditative prayer is an irony frequently noted by his detractors.

EDIT: the white background was bugging me.