"Planet number four is square in the habitable zone. Prime candidate in fact. Zero point nine six G's at the surface. Oceans. Landmass. High likelihood of living biosphere. It's beyond your most optimistic projections for Origae-6."
Ricks (from Alien: Covenant)

Planet 4, also referred to as the fourth planet, the Engineer Planet, and Paradise, was the planet that the USCSS Covenant, on its way to Origae-6, set out to explore after receiving a rogue transmission from its location. The planet had at least one large city populated by the Engineers.


"How did we miss this? We scanned the entire sector."
―Katherine Daniels[src]

Planet 4 was the fourth of five planets orbiting an ancient star in a system located in Sector 87.[1] It had two moons of its own, each smaller than Earth's. The atmosphere consisted of 19.5% oxygen, 79.4% nitrogen, and was 15.4 PSI in barometric pressure.

The planet's ecosystem was drastically altered by David when he unleashed the Chemical A0-3959X.91 – 15 pathogen on the Engineer's city. As a result of this event, all non-botanical life was either exterminated or used as an incubator for the gestation of hybridized predatory creatures such as the Neomorphs.


Before David's cleansing of Planet 4, the planet was populated with at least one city of Engineers. After David's experimentation with the pathogen, Planet 4 became home for the Neomorph species that were spawned from airborne spores released from mutated egg sacks, and for the Praetomorph species after David created Ovomorphs containing Facehuggers.

Exploration by Weyland-Yutani[]

Sometime after the Covenant departed Planet 4, a team from Weyland-Yutani arrived on the planet to investigate David's actions. While exploring the lab to document the rogue synthetic's scientific discoveries, one of the explorers inspected an Ovomorph and was attacked by a Facehugger.[2]

Behind the scenes[]


While Planet 4 is not the official name given to the uncharted world by any of the crew on the Covenant, "Planet 4 / Main Theme" is the name of track 6 from Alien: Covenant's official soundtrack, which plays twice, in relation to the planet. The first is while Mother pinpoints this planet as the origin of the rogue transmission. The second is while the USCSS Covenant is on its way to the planet.

Earlier versions[]

In an early version of the Alien: Covenant script by John Logan, the pathogen that David unleashed on Planet 4 did not kill all animals. During their investigation, the crew of the Covenant stumble upon several animals that have been affected by the pathogen.[3] In the final film, the pathogen eradicated all of the non–botanical lifeforms on Planet 4.

The script also notes that after David unleashed the pathogen, an energy barrier was activated by two satellites orbiting the poles as a quarantine barrier to prevent ships from leaving and the pathogen from spreading offworld. To restore power and communication to the Covenant, the crew destroy one of those satellites. This was excluded in the final film.



Concept art[]