The Eleos XII inside the Ryton Nebula
Lifeform born from the nebula
The Ryton Nebula was an apparent gaseous cloud located in the Ryton system of the Beta Quadrant. It interfered with and degraded the functioning of spacecraft, most significantly sensors and communications, and contained at its center a gravity well surrounded by a dense asteroid field.
In 2401, the SS Eleos XII hid from Vadic's forces inside the Ryton Nebula. Responding to a distress call from Doctor Beverly Crusher, the USS Titan-A arrived in the system and was confronted by Vadic's ship, the Shrike. During the ensuing battle, the Titan entered the nebula in a bid to evade the Shrike, where it encountered periodic, anomalous energy waves with both electrical and biological properties. The Shrike proceeded to disable the Titan and send it coasting into the nebula's central gravity well.
From the increasing frequency and narrowing intensity of the energy waves, Crusher realized that the nebula was in fact a "womb" for space-dwelling organisms. The gravity well was consuming matter and reconstituting it into the energy waves, which were akin to contractions building to a final birthing event. With this revelation, the Titan crew devised a means to power the ship from the final, massive energy wave and ride it out of the nebula. As they did so, the nebula dissipated, revealing a large swarm of newly born lifeforms. (PIC: "The Next Generation", "Seventeen Seconds", "No Win Scenario")
The nebula's name was seen on a screen on the Titan.
According to Terry Matalas, the Ryton Nebula lifeforms were "not the same species, but similar" to the beings from TNG: "Encounter at Farpoint", which Picard had coincidentally referenced earlier in the same episode. [1]