Ephsu I

From Halopedia, the Halo wiki

Ephsu I
Zeta Halo


Ephsu system[1]

Orbital position:

First planet








"Not much around except that super hunk of rock out there blocking our target."

Ephsu I is the sole planetary body in the Ephsu system.[1] It is a massive, uninhabited terrestrial world that has an atmosphere and water present. The planet was most noteworthy for being the anchor for Installation 07.


While Zeta Halo has a history of being "different," the Forerunners typically endeavored to position the rings around gas giants so that societies would not form in the shadow of the ring and to avoid it luring in potential settlers.[1] Rion Forge surmised that – given the circumstances in which the Halos had been dispersed and fired – the Forerunners had run out of time to find a gas giant to anchor it in a suitable firing position, or that one simply did not exist in the sector. As of late August 2558[2][Note 1] Zeta Halo stood at a distance of fewer than 12,000 kilometers from the planet.[1]

In December 2559, during the Battle for Zeta Halo, Zeta Halo was rocked by a cataclysmic explosion. Shortly thereafter, it was suddenly moved from in orbit around Ephsu I to an unknown location in space[3] by Cortana.[4]


List of appearances[edit]


  1. ^ Chapter 1 states that it happens in August, and it was three weeks prior to the events in the prologue, which takes place in orbit. Given no date change listed in the chapter heading, it is most likely approaching the end of August.


  1. ^ a b c d e Halo: Point of Light, chapter 8
  2. ^ Halo: Point of Light, chapter 1
  3. ^ Halo Infinite
  4. ^ Halo: The Rubicon Protocol, page 258