This page contains information regarding Star Trek: Discovery, and thus may contain spoilers.
The Red Angel was an entity that appeared to be related to red bursts, an unusual phenomenon observed by Starfleet in the late 2250s. Evidence suggested it to be a female Human time traveler wearing a mechanized suit and exhibiting technology that was far beyond present Federation capabilities. A mind meld revealed emotions of loneliness and desperation. (DIS: "Point of Light", "The Sound of Thunder", "If Memory Serves")
The term Red Angel originated with Spock, who claimed to have encountered it during his youth. The term was later adopted by the crew of Discovery, which had been tasked with studying the red burst phenomenon. Its appearance could not be linked to any winged or avian lifeforms in the Federation. (DIS: , "Point of Light", "An Obol for Charon")
According to the beliefs of the New Eden settlers, during Earth's third world war in 2053, a group of soldiers and civilians took refuge from bombings in the East Fork Presbyterian Church in Richmond, Indiana. A mysterious entity, "surrounded by pillars of fire", entered the building, bringing the church and everyone in it thousands of light years away to the planet Terralysium unharmed. (DIS: "New Eden")
They survived on the planet for two centuries, and created a religion which ascribed religious importance to the entity. Investigating a red burst in 2257, Captain Christopher Pike and an away team visited the planet where Amesha shared the story of the Red Angel with them. Pike later obtained the helmet camera video footage, which showed a red, angel-like figure. (DIS: "New Eden")
Spock, as a child, claimed that the Red Angel had spoken to him on several occasions, most notably when it told him where to find his foster sister, Michael Burnham after she tried to run away from home. Amanda and Sarek had always assumed that Spock used logic to find Burnham and wrote the Red Angel off as a figment of Spock's imagination, an opinion Amanda reconsidered after being shown more reports of the angel in the late 2250s. (DIS: "Point of Light")