An Aurora Unit, often abbreviated as AU, is a biological supercomputer created by the Galactic Federation. Aurora Units were introduced in Metroid Prime 3: Corruption and are, so far, only found in that game. There are only four Aurora Units mentioned throughout the game, but their names are followed by a three-digit number, suggesting that there are numerous amounts of Aurora Units. Even though there are four, one of them is mentioned and never seen throughout Corruption. Aurora Units are large creatures best described as "mechanical brains." They live inside of presumed life-supporting chambers, with the exception of the Dark Samus's corrupted Aurora Unit 313. It is interesting to note that both Aurora Units that Samus speaks to (Aurora Units 242 and 217) use "we" instead of "I." Also, these Aurora units are able to convey messages at each other, this may imply that all Aurora Units are linked somehow.
Aurora Unit 242
- Main article: Aurora Unit 242
Aurora Unit 242 is the first Aurora Unit Samus meets. 242 has its current location is aboard the G.F.S. Olympus. This unit instructs Samus toward her next objective throughout Corruption. 242 has a female voice.
Aurora Unit 217
- Main article: Aurora Unit 217
Aurora Unit 217 is the Aurora Unit based in SkyTown Elysia. 217 was corrupted with a virus as Elysia was invaded by a Leviathan. The virus is removed as Samus uploads the Federation created vaccine. After this, Samus is free to receive aid and instructions from 217. 217 has a male voice.
Aurora Unit 486
- Main article: Aurora Unit 486
Aurora Unit 486 has the least amount of information presented about it. It is only mentioned in Galactic Federation scans. It is said to have transformed Norion to a thriving forest planet.
Aurora Unit 313
- Main article: Aurora Unit 313
Spoiler warning:The following contains key plot or intense ending details.
Aurora Unit 313 was once the Aurora Unit aboard the G.F.S. Valhalla. This unit, however, was ripped out of its station and taken over by Dark Samus. Dark Samus armed the creature and forced it to attack Samus. Dark Samus also, at the end of Samus's visit to Phaaze, merged itself with 313, making Aurora Unit 313 the final boss in Metroid Prime 3: Corruption. 313, along with Dark Samus, were destroyed by Samus.
- The Aurora Units resemble Mother Brain in appearance, and it is hinted in an image from one of the trailers of Metroid Prime 3: Corruption that a future Aurora Unit complex would be the basis for her base on Planet Zebes in Super Metroid. The area in the trailer appears nearly identical to the base in architecture. This hints that the Space Pirates may have taken over the future complex of Aurora Unit 242 and implanted in Mother Brain, or could have possibly reverted 242 into their own new version of her after her defeat on Zebes in the original Metroid.
- The Aurora Units, in both appearance and function, resemble the Engineers from the Halo video game series. Whether this can be taken to imply that the Engineers are in turn inspired by Mother Brain's form and function is debatable.